/zsy &/ 6 & HARVARD UNIVERSITY % Library of the Museum of Comparative Zoology PSYCHE A Journal of Entomology Volume 87 1980 Editorial Board Frank M. Carpenter, Editor P. J. Darlington, Jr. W. L. Brown, Jr. H. W. Levi E. O. Wilson Alfred F. Newton, Jr. B. K. FfOLLDOBLER R. E. SlLBERGLIED Ronald J. McGinley Published Quarterly by the Cambridge Entomological Club Editorial Office: Biological Laboratories 16 Divinity Avenue Cambridge, Massachusetts, U.S.A. The numbers of Psyche issued during the past year were mailed on the following dates: Vol. 86, no. 2-3, for 1979: June 25, 1980 Vol. 86, no. 4, for 1979: December 19, 1980 Vol. 87, no. 1-2, for 1980: April 27, 1981 fsy ISSN 0033-2615 (jp f&& PSYCHE A JOURNAL OF ENTOMOLOGY founded in 1874 by the Cambridge Entomological Club Vol. 87 1980 Nos. 1-2 CONTENTS Functional Monogyny, Sexual Behavior, and Karyotype of the Guest Ant, Leplolhorax provanchera Emery (Hymenoptera, Formicidae). Alfred Buschinger, Andre Francoeur, and Karl Fischer . A Defensive Function for the Stabilimenta of Two Orb Weaving Spiders (Araneae, Araneidae). Charles C. Horton . Nesting Biology of Oxybelus sericeus with a Discussion of Nest Guarding by Male Sphecid Wasps (Hymenoptera). Alan W. Hook and Robert W. Matthews . Ecological History of Baelisca berneri Tarter and Kirchner from a West Virginia Stream (Ephemeroptera: Baetiscidae). William R. Morris, Dwight L. Chaffee, and Donald C. Tarter . Morphology of the Sternal Glands of Polistes fuscatus and P. canadensis (Hymenoptera: Vespidae). David C. Post and Robert L. Jeanne . Sanitary Behavior by the Social Spider Malios gregalis (Dictynidae): Distribution of Excreta as Related to Web Density and Animal Movements. William J. Tietjen . A Synopsis of the Chrysidid Genera of Neotropical America (Chrysidoidea: Hymenoptera). Lvnn S. Kimsey and Richard M. Bohart . Observations on the Web and Behavior of Wendilgarda Spiders (Araneae: Theridiosomatidae). Jonathan Coddington and Carlos E. Valerio . Studies on North American Carboniferous Insects. 6. Upper Carboniferous Insects from Pennsylvania. Frank M. Carpenter . Life History of Dysodia sica (Lepidoptera: Thyrididae) in Panama. Annette Aiello . Use of Artificial Nests for Rearing and Studying Polistes Wasps. Stefano Turillazzi . 1 13 21 39 49 59 75 93 107 121 131 Erratum 141 CAMBRIDGE ENTOMOLOGICAL CLUB Officers for 1979-1980 President . Norman Woodley Vice-President . Matthew Douglas Secretary . Heather Herman Treasurer . Frank M. Carpenter Executive Committee . William A. Neil Roger Swain EDITORIAL BOARD OF PSYCHE F. M. CARPENTER (Editor), Fisher Professor of Natural History, Emeritus, Harvard University W. L. BROWN, Jr., Professor of Entomology, Cornell University and Associate in Entomology, Museum of Comparative Zoology P. J. DARLINGTON, Jr., Professor of Zoology, Emeritus, Harvard University B. K. HOLLDOBLER, Professor of Biology, Harvard University H. W. LEVI, Alexander Agassiz Professor of Zoology, Harvard University R. J. McGlNLEY, Assistant Professor of Biology, Harvard University ALFRED F. Newton, Jr., Curatorial Associate in Entomology, Harvard University R. E. SlLBERGLIED, Associate Professor of Biology, Harvard University E. O. Wilson, Baird Professor of Science, Harvard University PSYCHE is published quarterly by the Cambridge Entomological Club, the issues appearing in March, June, September and December. Subscription price, per year, payable in advance: $9.50, domestic and foreign. Single copies, $3.50. Checks and remittances should be addressed to Treasurer, Cambridge Entomo¬ logical Club, 16 Divinity Avenue, Cambridge, Mass. 02138. Orders for missing numbers, notices of change of address, etc., should be sent to the Editorial Office of Psyche, 16 Divinity Avenue, Cambridge, Mass. 02138. For previous volumes, see notice on inside back cover. IMPORTANT NOTICE TO CONTRIBUTORS Manuscripts intended for publication should be addressed to Professor F. M. Carpenter, Biological Laboratories, Harvard University, Cambridge, Mass. 02138. Authors are expected to bear part of the printing costs, at the rate of $24.50 per printed page. The actual cost of preparing cuts for all illustrations must be borne by contributors: the cost for full page plates from line drawings is ordinarily $18.00 each, and for full page half-tones, $30.00 each; smaller sizes in proportion. The December, 1979, Psyche (Vol. 86, No. 4) was mailed December 19, 1980. The Lexington Press, Inc., Lexington, Massachusetts PSYCHE Vol. 87_1980 _Nos. 1-2 FUNCTIONAL MONOGYNY, SEXUAL BEHAVIOR, AND KARYOTYPE OF THE GUEST ANT, LEPTOTHORAX PROVANCHERI EMERY (HYMENOPTERA, FORMICIDAE) By Alfred Buschinger 1 , Andre Francoeur 2 and Karl Fischer 1 1) Introduction The ant species Leptothorax provancheri was first detected by Provancher (1881, 1883) near the actual Quebec metropolitan region, in the locality of Cap-Rouge, Comte de Quebec, and described under the name Myrmica tuberum Fabricius. Emery (1895) recognized it as a new species to which he gave the present name. Following Creighton (1950), L. emersoni Wheeler (1901) and L. emersoni hirtipilis Wheeler (1917) are synonyms of L. provancheri. Thus the range of this species extends from eastern Canada and New England west to Alberta, and, with the subspecies L. provancheri glacialis Wheeler (1907), south to Colorado and northern New Mexico (Gregg, 1963). The subspecies glacialis is not recognized by other American myrmecologists. There is no sound basis to retain it at this moment. In the Catalog of Hymenoptera North of Mexico (U.S.N.M.), D.R. Smith did not retain it (1979). L. provancheri is allied to the subgenus Mychothorax Ruzsky, or Leptothorax sensu Smith (1950). Biological observations were made by Wheeler (1901, 1903, 1910). From these it is known that L. provancheri (= emersoni) and its subspecies all are living together with host ants of the genus Myrmica, in a manner which resembles most the relations of Formicoxenus to its Formica hosts (xenobiosis). This means that L. provancheri constructs small nests in the earthen walls of the 'Fachbereich Biologie, Institut fur Zoologie, der Technischen Hochschule, D 6100 Darmstadt, Schnittspahnstr. 3; and 2 Universite du Quebec, Chicoutimi, Quebec, Canada G7H2B1 Manuscript received by the editor September 15, 1980. 1 2 Psyche [Vol. 87 Myrmica host colony, where the provancheri brood is normally kept apart from the Myrmica chambers. However , provancheri workers enter the galleries of their hosts, frequently mount the Myrmica workers, and apparently gain food by vigorously licking (“sham¬ pooing”—Wheeler 1910) and begging their victims. Soon after the description ofL. emersoni Wheeler (1901), Holliday (1903) published a very accurate and comprehensive study on the peculiar polymorphism of this little ant. She described, measured and dissected more than 1000 specimens from over 20 nests, and she discovered that only very few winged or dealate females were among them. About one third of all female individuals had to be character¬ ized as “microgynes, ergatoid females, triocellate, biocellate and uniocellate workers”, the remaining specimens were macroergates and microergates. Holliday also found out that all these ants had rather well developed ovaries, and a typical spermatheca. Surprising¬ ly, she failed to judge whether sperm was present in the receptacula or not. Recently we had investigated the social structures of the guest ants, Formicoxenus nitidulus (Buschinger and Winter 1976) and F. hirticornis (= Leptothorax hirticornis Emery) (Buschinger 1979) both of which have a polymorphism similar to that of L. provancheri, and a “functional monogyny” with always one fertile queen per nest, and often several inseminated but sterile “replacement queens” in addition. Fertile and sterile females there may either be normal, dealate queens or intermorphs, both often occurring together in the same colony. Thus we wanted to find out whether a similar system might be present in L. provancheri. With respect to a possible relationship between provancheri and Formicoxenus we further studied the sexual behavior, and the karyotype of this species. 2) Material and Methods Leptothorax provancheri was collected in a moist pasture with a small rocky outcrop beside a gravel road, in the municipality of St- Augustin, near the limits of Ste-Catherine, Comte de Portneuf, on 23 August 1979. The guest ant and its host had developed flourishing populations only in the rocky part of this open habitat. Colonies were located in the soil and between the roots of grass and herbs growing on the flanks and atop of the rounded rocky outcrops of the meadow. The host species, Myrmica incompleta Provancher, inhabits these 1980] Buschinger, Francoeur, & Fischer —Leptothorax 3 sites in large, polygynous colonies which sometimes extend over more than 1 m 2 . We could regularly identify, in different Myrmica colonies, several brood chambers of provancheri, the content of which, adults and immatures, was removed carefully with an aspirator. The ants from one brood chamber, together with a few individuals crawling in the soil in the immediate vicinity of the chamber, were considered as belonging to one “colony unit”. We stress that normally these colony units, found within one Myrmica nest, were clearly separated from each other by several decimeters. Nevertheless we cannot completely exclude the possibility that two chambers belonged to one colony unit (one society), or that specimens from two colony units separated by smaller distance were mixed together. Soon after in the laboratory the numbers of males, females, intermorphs, workers, and pupae were counted (Table I). All female individuals of several representative samples were dissected and their reproductive state was evaluated as described by Buschinger and Winter (1976) and Buschinger and Alloway (1978). We prefer to define castes only by the function: queens are inseminated, fertile individuals, irrespective of their morphological aspect. The morpho¬ logical differences between alate or dealate females, “workers” in the Table 1: Numbers of individuals, adults and pupae, in 15 Leptothorax provancheri, as counted immediately after collecting. colony units of Nr. <3<3 dealate 5$ Inter- Ergato- morphs morphs (3-pupae alate 9-pupae Interm. pupae Ergatom. pupae 1 2 — 1 i 9 34 9 — 24 16 3 3 — 7 71 9 — 5 15 4 2 — 5 26 7 — — 10 5 22 — 6 60 . 18 — 11 27 7 5 — 9 36 10 _ 16 23 8 8 1 21 30 26 3 31 14 9 — — 3 6 — — 1 8 10 2 — I 6 2 — — — 11 1 — 3 21 6 — 3 15 12 — — 4 13 — — 2 5 13 — — 13 29 7 — 8 17 14 — — 12 22 — — 11 9 15 1 — 14 20 2 — 19 7 2 44 2 109 375 96 3 131 166 4 Psyche [Vol. 87 morphological sense, and individuals between these (“intercasts”) are indicated by the terms “gynomorph”, “ergatomorph” and “inter- morph” (Buschinger and Winter, 1976, Buschinger 1978). The remaining colonies were kept and observed in the laboratory. From October 1979 to February 1980 they hibernated under natural temperature conditions at Darmstadt/FRG. After a severe frost period with temperatures reaching —12°C many adults were dead, but could still be dissected. The larvae survived, and a small number of sexuals and workers hatched until the end of March. Sexual behavior was observed immediately after collecting the ants in the field, and during the first half of September, in the laboratory. Karyotype studies were made following the method of Imai, Crozier and Taylor (1977), with male pupae collected in the field. 3) Female Polymorphism and Functional Monogyny The ant material was collected when sexual pupae and some newly eclosed sexuals were present in the nests. In Table I we did not distinguish between ergatogynes, uni-, bi- and triocellate workers, as was done by Holliday (1903); however, all these different forms did occur, alongside with alate or dealate gynomorphs and ergatomorphs without ocelli, like in the population studied by Holliday. We comprised all intermediate forms between alate/dealate females and apparently normal workers without ocelli as “intermorphs”. Table I reveals, at the first glance, that alate and dealate gynomorphs, and their pupae, are extraordinarily rare among the collected ants. Altogether we found 5 such specimens in 15 colony units, as compared to 240 intermorphs and 541 ergatomorphs. The respective numbers from Holliday (1903) are the following: queens (including microgynes): 36, intermorphs: 411, workers (including macroergates): 624 (These numbers, however, refer only to adults). The different numerical relations between adult intermorphs and ergatomorphs (109:375) and the immatures (131:166) in our material could indicate that workers preferably remain with their colony unit, whereas a considerable part of the intermorphs might leave the nest, mate and start new colonies. Further evidence for this interpretation is strongly provided by the dissections. Since it is difficult to include all the various combinations of different female forms and their reproductive function in a table, we will give the results of our dissections hereafter for each colony unit separately. Numbers correspond to those in table I. 1980] Buschinger, Francoeur, & Fischer —Leptothorax 5 Adults of 6 samples were dissected immediately after collecting: No. 1: A single intermorph, with 3 ocelli, apparently alone in a small chamber in the host nest. Spermatheca filled with sperm, 6 ovarioles of about the length of the gaster, developing eggs. Presumably a queen independently founding a new colony. No. 2: Colony contains a dealate, normal queen, who was observed to lay eggs. Since the colony is still alive, only a few specimens were dissected immediately after collecting: 4 callow intermorphs had only very short ovarioles (4, 5, 6 and 7 respectively), the receptacula were present, but empty. 3 workers (without ocelli) had 5 (2 $ ), and 6(1$) short ovarioles, receptacula could not be found. This is different from Holliday’s experiences: she found receptacula even in “microergates”. However, the number of workers without receptaculum was low in our material as well (see below). No. 6: One intermorph with dark spots at the normal position of the wings (between ergatoid female and triocellate $ of Holliday 1903), with 6 long ovarioles, corpora lutea and the spermatheca filled with sperm — a functional queen. One $ with 5 ovarioles and without spermatheca. Presumably a young colony. No. 9: One workerlike intermorph with two tiny ocelli, but 6 long ovarioles, corpora lutea, and filled spermatheca —the functional queen. 4 intermorphs with empty receptacula, 3 ergatomorphs without spermathecae, and one ergatomorph with an empty recep¬ taculum, but with 6 ovarioles of about the length of the gaster, and a few tiny corpora lutea (egg-laying worker). No. 11: One intermorph with 3 ocelli, the functional queen; 4 intermorphs and one ergatomorph with filled receptacula, but not egg-laying; one intermorph (callow) with empty receptaculum, 10 ergatomorphs with empty receptacula, one ergatomorph with empty receptaculum, but with corpora lutea; 3 workers without receptacula. Again a rather complete colony. No. 12: One intermorph with 3 ocelli, the functional queen; 3 intermorphs inseminated but not egg-laying; one intermorph with empty spermatheca; 7 ergatomorphs with empty receptacula, one ergatomorph with empty spermatheca, but with corpora lutea; 2 workers without spermathecae. Complete colony. It is striking that, notwithstanding all the uncertainties which are due to the difficult collecting of complete colonies, most of our samples (No. 2, 6, 9, 11, 12) contained one fully fertile queen, and often a number of inseminated, but sterile individuals. The latter are 6 Psyche [Vol. 87 by no means always young and recently inseminated. Callows were easily distinguished from older individuals by their coloration, and by very short and thin ovarioles. Furthermore the fat body of most inseminated individuals looks somewhat different in its color from that of callows. Thus, we are sure that most of the inseminated, sterile “replacement queens” had mated during the previous year, and remained in their mother colonies. This would correspond to the “functional monogyny” in Formicoxenus (Buschinger and Winter 1976, Buschinger 1979). The results of the dissection of individuals from further 5 colonies which were kept alive until spring 1980, do also fit into this interpretation: No. 3: 10 individuals died during hibernation and could be dissected. There was one intermorph whose spermatheca was filled with sperm, however the ovarioles were short. Two ergatomorphs exhibited the same condition. One intermorph and one ergatomorph had empty receptacula; two intermorphs and 3 ergatomorphs were found to have no spermathecae. We suggest that, in this colony, the fertile female had died during the laboratory culture, or that the sample represents only part of a colony the queen of which was lost during collecting. No. 4: During hibernation 17 individuals died and were dissected. Among them was one intermorph with the spermatheca filled with sperm, with 6 ovarioles of about the specimen’s total length, with corpora lutea: the functional queen of this colony. 8 intermorphs were inseminated, but had short ovarioles, 2 had empty receptacula. However, among the ergatomorphs there were further two with filled receptacula, two with empty receptacula, and two without recep¬ tacula. One of the latter nevertheless was fertile, this means she had ovarioles of about half her body’s length, and corpora lutea. No. 5: 24 individuals died during hibernation. One intermorph with 8 long ovarioles, corpora lutea, and spermatheca filled with sperm, the functional queen; 9 additional intermorphs had filled receptacula, but were not egg-laying; 8 intermorphs and 3 ergatomorphs had empty receptacula; two ergatomorphs with empty receptacula and one $ without receptaculum had small corpora lutea indicating a previous egg-laying. No. 14: Four specimens died during hibernation: Oneergatomorphic individual was the functional queen, one ergatomorph had a spermatheca filled with sperm, and two workers had no spermathe¬ cae. 1980] Buschinger, Francoeur, & Fischer —Leptothorax 7 No. 15: Six individuals could be dissected; one intermorph and four ergatomorphs had empty receptacula, one worker had no spermathe- ca. The remaining specimens from these 5 colonies could not be dissected because they were too much decomposed when found dead. The same happened with all individuals from colonies no. 7,8 and 10. However, among the 5 colonies we had again 3 with one functional queen (no. 4, 5, 14), and there were inseminated but sterile specimens in these colonies, always together with a functional queen. Thus we believe that the social organization of Leptothorax provancheri, like that of Formicoxenus nitidulus (Buschinger and Winter, 1976), and F. hirticornis (Buschinger 1979), is a “functional monogyny”, with always one fully fertile queen in a colony unit, and with often several inseminated but sterile “replacement queens”. Such queens could possibly found own colonies by budding, together with a few workers from the mother colony. However, founding of colonies by single newly inseminated females alone may also occur (cf. no. 1). It is interesting that a few intermorphs and ergatomorphs, without being Fig. 1: Sexual calling behavior of a Leptothorax provancheri female (ocellate intermorph). The stinger is extruded. 8 Psyche [Vol. 87 inseminated, may be fertile as is shown by the presence of corpora lutea in their ovarioles. 4) Sexual Behavior of Leptothorax provancheri The sexual behavior of L. provancheri is, as far as observed, identical with that of Formicoxenus nitidulus (Buschinger 1976), Harpagoxenus sublaevis (Buschinger 1972) and other species of the Mychothorax group and their social parasites. This means that sexually active females emerge from the nests, climb atop of the nest chamber or any other object in the formicary, raise the gaster and present, with the stinger extruded, a sexual pheromone. With L. provancheri we observed, in the morning between about 9 and 11 a.m., several intermorphs and ergatomorphs exhibiting this “Lock- sterzel” behavior (Fig. 1). After all males had died by 15 September in colonies no. 3 and 10, the females remained active until 29 September when the colonies were put into hibernation temperatures. The males are attracted by poison gland secretion of the females, as in the other species cited above. They mount the females (Fig. 2), and the copulation differs by no means from what was observed in Formi¬ coxenus. The behavior of alate females could not be studied. Fig. 2: L. provancheri male mounting a calling intermorph. 1980] Buschinger, Francoeur, & Fischer —Leptothorax 5) Karyotype of Leptothorax provancheri Nine male pupae from four colonies (colony no. 1: 2 pupae, no. 2: 3 p., no. 3: 1 p., no. 8: 3 p.) were used for karyotype studies. A total of 67 metaphases were found with 11 chromosomes each, whereas two had the diploid number of 22, and two others had 8 and 21 chromosomes respectively. In the latter two cells, a haploid and a diploid one, the missing chromosomes presumably have been lost during the prepara¬ tion. Thus the haploid number of chromosomes in Leptothorax provancheri males is n= 11 (Fig. 3). All chromosomes are metacentric or submetacentric. They range continuously in size with the smallest of about half the length of the largest. The chromosome number of Formicoxenus nitidulus is n=15. Thus a closer relationship between L. provancheri and Formicoxenus cannot be demonstrated with a comparison of the karyotypes. However, chromosome numbers vary often between closely related species among the Leptothoracini. So, for example, Harpagoxenus sublaevis has n=20 and Harpagoxenus canadensis n=18, Leptothorax muscorum (Nyl.) n=17 and L. gredleri Mayr, formerly synonymized with L. muscorum, has n= 11! 10 Psyche [Vol. 87 6) Discussion The present study has described various aspects of the biology of Leptothorax provancheri. With respect to polymorphsim in the female sex we can confirm the observations of Holliday (1903) with a difference only in the proportion of workers (ergatomorphs) without receptacle. While Holliday found only one such specimen in her large material from Colebrook, Conn., we had 24 workers without a receptacle as compared to 42 ergatomorphs with a receptacle. Furthermore, we found 2 intermorphs, both workerlike, but with ocelli present, without a spermatheca. It is a striking peculiarity ofL. provancheri that all morphologically different females, from dealate gynomorphs to seemingly normal workers (colony no. 9) may have receptacula and may even function as queens. Sometimes (e.g. colony 9) intermorphs may live in a colony alongside an ergatomorphic queen (presumably their mother!). However, the same observation was made in Formicoxenus nitidulus (Buschinger and Winter 1976), where even sterile gynomorphs may exist in nests with intermorphic queens. A second striking fact is the presence of one or several inseminated females (not only newly fertilized ones) living together with the one fertile queen. Such a system, functional monogyny, has first been documented, among ants, in Leptothoraxgredleri Mayr (Buschinger 1968), an independent ant. However, this social organization seems to be a characteristic of guest ants, since it was also found in Formicoxenus nitidulus and F. hirticornis. At present, we cannot yet decide, whether functional monogyny represents a plesiomorphic character which the guest ants and L. gredleri share because of their descent from a common ancestor with this organization, or whether this system provides any selective advantage for life as a guest ant. As already briefly discussed in section 4 and 5, the sexual behavior of L. provancheri and the karyotype as well do not provide significant arguments in favour of or against the hypothesis of a common phylogenetical origin of the guest ants. The sexual behavior, with females “calling” for males by use of a poison gland secretion as sexual pheromone, is common among Leptothoracini, especially among the social parasitic species. Thus, our data are not yet sufficient to prove that L. provancheri should belong to the genus Formicoxenus, or that there is a closer 1980] Buschinger, Francoeur, & Fischer —Leptothorax 11 relationship among the guest ants than between these and other Leptothoracini. On the other hand, the observations clearly confirm that L. provancheri at least belongs to a group of Leptothoracini assembling around the subgenus Mychothorax (= Leptothorax Smith), a group among which also Formicoxenus, Harpagoxenus and Doronomyrmex have to be classed. Summary L. provancheri was collected from a site in the municipality of St- Augustin, Comte de Portneuf, Quebec. This guest ant was living together with M. incompleta Provancher (=brevinodis Emery). We found several nests within the nesting areas of large, polygynous Myrmica colonies. From dissecting representative samples we con¬ clude that L. provancheri has a social organization similar to that of Formicoxenus, a functional monogyny”. This means that each colony unit contains one fully fertile queen, which may be a dealate, an intermorphic, or even ergatomorphic specimen; and several fertilized, but sterile females. We can confirm the observations of Holliday (1903) stating that nearly all female individuals, most ergatomorphs, intermorphs of various degrees, and alate females, possess a well developed spermatheca. Sexually active females exhibit a sexual calling behavior (Locksterzeln) like the one described for Formicoxenus and other social parasites related to the subgenus Leptothorax (= Mychothorax Ruzsky). The haploid chromosome number is 11. This is different from Formicoxenus nitidulus (n= 15). Whether L. provancheri belongs to the genus Formicoxenus cannot yet be decided. Literature Cited Buschinger, A., 1968. Mono- und Polygynie bei Arten der Gattung Leptothorax Mayr (Hymenoptera, Formicidae). Ins. soc. 15: 217-226. 1972. Giftdrusensekret als Sexualpheromon bei der Ameise Harpagoxenus sublaevis. Die Nalurwissenschaften 59: 313-314 1976. Giftdrusensekret als Sexualpheromon bei der Gastameise Formicoxenus nitidulus (Nyl.) (Hym., Form.). Ins. soc. 23: 215-226 1978. Queen polymorphism in ants. Reunion Scientifique de la Section Franpaise UIEIS, 1978, Besanpon, Bull. Interieur 1978: 12-22 1979. Functional monogyny in the American guest ant Formicoxenus hirti- cornis (Emery) (= Leptothorax hirticornis), (Hym., Formicidae). Ins. soc. 26: 61-68 12 Psyche [Vol. 87 Buschinger, A. and T. M. Allow ay, 1978. Caste polymorphism in Harpago- xenus canadensis M.R.Smith (Hym., Formicidae). Ins. soc. 25: 339-350 Buschinger, A. and U. Winter, 1976. Funktionelle Monogynie bei der Gasta- meise Formicoxenus nitidulus (Nyl.) (Hym., Form.) Ins. soc. 23. 549-558 Creighton, W.S., 1950. The Ants of North America. Bull. Mus. Comp. Zool., Harvard Univ. 104: 1-585 Emery, C., 1895. Beitrage zur Kenntnis der nordamerikanischen Ameisenfauna. Zool. Jb. Syst., Geogr., Biol. Tiere 8: 257-360 Gregg, R.E., 1963. The Ants of Colorado. University of Colorado Press, Boulder. 792 pp. Holliday, M., 1903. A Study of Some Ergatogynic Ants. Zool. Jb. Syst. Okol. Geogr. Tiere 19: 293-328 I mai, H.T., Crozier, R.H., and R.W. Taylor, 1977. Karyotype Evolution in Australian Ants. Chromosoma 59: 341-393 Provancher, L, 1881. Faune canadienne. Formicides. Natural. Canad. 12: 353- 360 1883. Petite faune entomologique du Canada. Vol.2. Darveau, Quebec. 831 pp. Smith, D.R. 1979. Formicidae, in Catalogue of Hymenoptera in America North of Mexico, vol. 2, Apocrita (Aculeata) (K.V. Krombein, ed.) Smithsonian Inst. Washington, D.C. Pp. 1323-1467. Smith, M.R., 1950. On the Status of Leptothorax Mayr and some of its subgenera. Psyche 57: 29-30 Wheeler, W.M., 1901. The Compound and Mixed Nests of American Ants. Amer. Nat. 35: 431-448 1903. Ethological Observations on an American Ant (Leptothorax emersoni Wheeler). Arch. Psychol. Neurol. 2: 1-31 1907. Notes on a New Guest Ant. Leptothorax glacialis, and the Varieties of Myrmica brevinodis Emery. Bull. Wis. Nat. Hist. Soc. 5: 70-83 1910. Ants. New York and London, XXV +661 pp. 1917. The Mountain Ants of Western North America. Proc. Amer. Acad. Arts Sci. Boston, 52: 457-569 A DEFENSIVE FUNCTION FOR THE STABILIMENTA OF TWO ORB WEAVING SPIDERS (ARANEAE, ARANEIDAE)* By Charles C. Horton Department of Biological Sciences University of Maryland Baltimore County (UMBC) 5401 Wilkens Avenue Catonsville, Maryland 21228 Stabilimenta consist of straight or zigzag bands of ribbon silk which are arranged in species and age-specific patterns within the free zone and sometimes the hub of the webs of many diurnally active orb¬ weaving spiders, including members of both major families of orb- weavers (Araneidae, Uloboridae). The relatively common occurrence of stabilimenta among the orb-weaving guild suggests that they have one or more important functions. Although a number of functions have been suggested (see Robinson and Robinson, 1970, 1973), the actual significance of any of these proposed functions has not yet been demonstrated (Levi, 1978). I present here experimental evidence which suggests that the stabilimenta of Argiope aurantia Lucas and A. trifasciata (Forskal) aid in defense against avian predators. The stabilimenta of all but the early instars of A. aurantia and A. trifasciata are vertical zigzags of silk located above and/or below the hub, where the spider rests. Early instars of A. aurantia, as well as the early intars of several other Argiope spp. produce a disc stabili- mentum. The vertical stabilimentum is also constructed by other Argiope sp. (e.g. A. bruennichi, A. lobata). Some Argiope spp. produce a cross stabilimentum composed of zigzags of ribbon silk arranged in the pattern of an “X” around the hub (e.g. A. argentata, A.florida, A. pulchella, A. savignyi). All Argiope spp. produce some form of stabilimentum (Levi, 1968). Argiope spp. reside during daylight hours at the hub of the web, a position which exposes them to potential predators. This exposure to potential predators suggests a defensive function for stabilimenta. Defensive functions for the stabilimenta of Argiope spp. have been suggested by various authors (Hingston, 1927; Marson, 1947; Lubin, * Manuscript received by the editor August 23, 1980. 13 14 Psyche [Vol. 87 1975; Tolbert, 1975) based on observations on natural populations. However, Robinson and Robinson (1970) performed experiments using model stabilimenta which indicated that birds could use stabilimenta as an aid to prey location. Thus, the defensive role of stabilimenta is not clear. I performed experiments in aviaries which consisted of exposing blue jays to a simultaneous choice among A. aurantia or A. trifasciata which exhibited different degrees of web completion, in order to assess the effect of the stabilimentum on avian predation. Materials and Methods The experiments were performed in aviaries which consisted of 1.6X6.2X2.3 m wire mesh enclosures located on the roof of Morrill Science Center, University of Massachusetts, Amherst. The basic experimental design was to offer blue jays ( Cyanocilla cristata) a choice among three spiders, each in a web at a different stage of completion; (1) suspended in the characteristic resting position, but entirely out of a web; (2) in a web without a stabilimentum; and (3) in a web with a stabilimentum. The blue jays used in the experiments had been taken as nestlings from their nests in the Amherst area and reared by hand. Thus they were naive with respect to spiders and their webs prior to experi¬ mentation. The blue jays were kept individually in the aviaries for several days prior to experimentation. Each bird was trained to recognize spiders as food by placing living spiders in its food tray (i.e., spiders free of webs). A given bird was used in the experiments when it took spiders readily (three within five minutes) without having previously been deprived of food. Prior to experimentation the birds were deprived of food overnight. Nine birds wre used, each bird being used one to four times. An attempt was also made to use starlings (Sturnus vulgaris ) and robins ( Turdus migratorius) in the experi¬ ments; they were found to be unsuitable. Penultimate and adult female A. aurantia and A. trifasciata were collected from field areas in and near Amherst, Massachusetts. The size and species of the spiders were the same within each choice set. In some cases, 6— 12 spiders were released into the aviary during the evening prior to experimentation, while the bird was isolated in a small cement-block enclosure (1.5X2.IX 1.4 m) at the rear of the aviary. Most of the spiders selected suitable web sites and built their 1980] Horton — Stabilimenta of Orb Weaving Spiders 15 webs within the aviary during the night and early morning. Three spiders were then selected—one having no web, one having a web without a stabilimentum and one having a complete web. The remaining spiders and their webs were removed. If none of the spiders had produced a web without a stabilimentum one web was randomly selected and its stabilimentum removed with a hot needle. The “non¬ web” spider was a spider which had suspended itself on a few strands in the normal resting position. In other cases the spiders used in the experiments had built their webs within aluminum frames (50X50X5 cm) with glass panels in the front and back which were removed prior to placing the frames in the aviaries. During an experiment, two of the frames contained spiders in webs, one with, and one without a stabilimentum. The third frame contained a spider which had been killed by freezing and was suspended by thread in the characteristic resting position in the center of the frame. The frames were placed in random order side-by-side on a table within the aviary. The data obtained from the experiments using spiders in frames were combined with data from spiders which had constructed their webs within the aviary. The second set of experiments was performed using pen and ink drawings of orb webs. These drawings were executed in white ink on a brown background, and were approximately the size of a normal, adult Argiope web. The drawings were suspended within the aluminum spider frames, using the same three web conditions used in the previous experiment. Crickets were suspended by thread in the position that would normally be occupied by the spider. The blue jays used were trained to recognize crickets as food, and were naive with respect to spiders and spider webs. Once the three webs or web drawings were in place, a blue jay was released into the aviary. Capture sequence, capture time, and the behaviors exhibited by the blue jays and the spiders were recorded. An attempt to capture a spider which resulted in only a portion being taken was scored as a capture. The null hypothesis in the experiment outlined above was that the web and stabilimentum would have no effect on predation. The alternative hypothesis was that these structures would inhibit predation. If the null hypothesis were valid, the capture sequence (i.e., which spider/cricket was taken first, second, third) would have been random. A nonrandom sequence, in which the non-web spider tended to be taken first, the partial web spider second, and the full web spider last, would support the alternate hypothesis. 16 Psyche [Vol. 87 Results and Discussion The results are divided into two groups. The first grouping is the response of inexperienced birds upon their first exposure to the choice between a non-web spider, a spider in a partial web, and a spider in a full web. The second group consists of all the succeeding response sequences of the birds which were used more than once. Table 1 shows the first capture exhibited by 11 birds on their first exposure to the experimental situation. These birds had had no previous experience with spiders in webs, but had had experience with spiders out of webs (in feeding trays). Although the data are too few to detect minor preferences, the first choice of the birds appears to have been random, suggesting that the birds had no innate aversion to spider webs and/or stabilimenta. Table 1. First Choice Among Three Web Conditions Exhibited by 11 Inexperi¬ enced Blue Jays. “N” Stands for the Non-web Spider, “P” the Partial-web Spider, and “F” the Full-web Spider. Possible Number of Choices Times Observed N 5 P 3 F 3 Although the first choice appears random, some degree of innate preference among the three choices cannot be ruled out on the basis of these data. It has been shown that slight differences in the stimulus pattern presented by Lepidoptera prey can alter or prevent the initial attack response of blue jays (Coppinger, 1968), and during my experiments the blue jays were confronted with a choice among three stimulus patterns which differed with respect to visual complexity. Thus, the discrimination shown by the blue jays in response to the spiders in their webs could have been affected by the differences in visual stimulus patterns among the choices. Accordingly, eight birds were given similar choices, using, however, web drawings and crickets as prey. In these experiments the visual stimulus pattern was essentially the same as in the experiment outlined above, but the tactile element of the web was missing. The results of the experiment with web drawings and crickets are summarized in Table 2. A Chi-square analysis indicates that the 1980] Horton — Stabilimenta of Orb Weaving Spiders 17 Table 2. Capture Sequences Exhibited by 8 Blue Jays Given a Choice Among 3 Crickets and Web Drawings Possible Capture Sequences Times Observed N-P-F 6 N-F-P 3 P-N-F 2 P-F-N 7 F-N-P 7 F-P-N 5 distribution of capture sequences did not differ from random (P>0.50), indicating that the blue jays did not discriminate among the three web drawings. The web drawings were of course not identical to the spider webs. However, the results suggest that the birds had no innate preferences among the three web conditions. Table 3 shows the observed capture sequences exhibited by six experienced birds (i.e., excluding the initial sequence of each bird). Of the six birds, four were used twice and two were used three times. The results clearly favor rejection of the null hypothesis since the probability ofthis oramoreextremedistributionis<0.001 (binomial expansion) (Steel and Torrie, 1976). The non-web spider was taken first in 13/14 of the cases, demonstrating that non-web spiders were preferred over spiders within webs. In these cases the birds were left with a choice between a complete web and a partial web (one which lacked a stabilimentum). Table 3. Capture Sequence Exhibited by Six Experienced Blue Jays Given a Choice Among Three Spiders (Abbreviations as in Table 1) Possible Capture Times Sequences Observed N-P-F 12 N-F-P 1 P-N-F 1 P-F-N 0 F-N-P 0 F-P-N 0 18 Psyche [Vol. 87 These birds selected the spider on the incomplete web 12/13 times. The results of the second choice are also clearly non-random and demonstrate that the stabilimentum had a negative influence. The results show that both the web and the stabilimentum inhibited predation by the blue jays. Comparison of the results obtained during the initial exposure of each bird with the results from subsequent trials indicates that this avoidance of webs and stabilimenta is a learned response. Initially the birds did not discriminate between the three choices, but they did so after experiencing web contact. After having contacted the webs the blue jays exhibited behaviors such as head shaking, wiping the beak, and preening. The birds displayed these cleaning behaviors for periods ranging from 30 seconds up to an hour after web contact. The web adhered to the feathers and caused some clumping, mainly of the head and breast areas. Cleaning activities were apparently directed at removal of the portions of the web which had adhered to the birds. It is possible that the web contains a substance which is noxious or toxic to birds when ingested. However, during the experiments, I observed some of the birds eating the webs after coming in contact with them. The fact that the birds ate the portion of the webs which adhered to their feathers suggests that the web did not contain noxious or toxic substances. Based on the behaviors exhibited by the blue jays, I suggest that the noxious quality of the web is due to the physical adherence of the web to the bird’s feathers, and the resulting clumping of the feathers. Apparently stabilimenta are constructed only by diurnally active orb-weavers. A second generalization is that many of the diurnal orb- weavers are conspicuously colored (Levi, 1968). Since it appears that the web is a noxious stimulus to birds, then it is reasonable to suggest that both the conspicuous coloration of the spider and the presence of stabilimenta make the web more obvious, thus facilitating avoidance by predators. The stabilimentum would then be analogous to aposematic (warning) coloration in insects. The stabilimentum and bright coloration would have an effect on visually orienting preda¬ tors, such as birds, and would be effective during daylight hours when such predators are active. This hypothesis of advertisement was originally discussed by Robinson and Robinson (1970), though they had no evidence of a noxious element. 1980] Horton — Stabilimenta of Orb Weaving Spiders 19 The observations of Robinson and Robinson (1970) which demon¬ strated that the cross stabilimentum couldbe used by birds as an aid in prey location also indirectly supports my hypothesis. Their experiments demonstrated that birds could key in on the stabiliment¬ um. However, in their study the model stabilimenta were paired only with a positive reinforcement (prey), resulting in attraction of the birds. In the natural situation, the stabilimentum probably facilitates avoidance, rather than attraction of predators, since it is paired with a negative stimulus, the webs. Conclusions Experiments performed with blue jays in aviaries showed that the birds preferred spiders which were not in their webs. A comparison of the behavior of inexperienced birds with that of the same birds after contacting the webs suggests that web avoidance is a learned response. This avoidance of contact with the web indicates that the orb-web constitutes a noxious stimulus to blue jays, and presumably to other avian predators. The noxious element appears to be the adherence of the web to the bird’s feathers, as indicated by extended bouts of cleaning behavior exhibited by the blue jays following web contact. The experiments also show that the stabilimenta of A. aurantia and A. trifasciata enhance the web avoidance response exhibited by blue jays. I propose that the stabilimenta of these species “advertise” the presence of the web, a noxious stimulus, in a manner analagous to aposematic coloration of some insects. The advertisement hypothesis of stabilimentum function does not exclude the possibility of other functions for this structure. The hypothesis that the web and stabilimenta inhibit avian predation is compatible with previous observations concerning the occurrence of stabilimenta in other araneids, suggesting the general applicability of the hypothesis. For example, as previously noted, stabilimenta are only constructed by diurnal orb-weaving spiders. Since nocturnal orb-weavers as a rule rest in a retreat near the periphery of the web during the day, residing in the hub only at night, they would be less exposed to visually orienting predators. Thus, according to this hypothesis, it would be predicted that the diurnally active araneids would be more likely to construct stabilimenta. A second observation concerning diurnal orb-weavers is that, in 20 Psyche [Vol. 87 general, they are conspicuously colored (Levi, 1968). This bright coloration could serve as additional advertisement of the web as a noxious stimulus. Acknowledgements Many persons have given me advice during this study; in particular I acknowledge the ideas and suggestions of Theodore D. Sargent, William B. Nutting, and Carolyn Cearley. I would like to thank Alan C. Kamil for providing the blue jays used in the study. This work represents a portion of a thesis submitted in partial fulfillment of the requirements for the Ph.D degree at the University of Massachusetts. A portion of the support for this study came from a Sigma Xi grant in the aid of research. References Coppinger, R.P. 1968. The effect of experience and novelty on avian feeding be¬ havior with reference to the evolution of warning coloration in butterflies. Ph.D. thesis (unpublished), Amherst College, Amherst, MA 01002. Hingston, R.W.G. 1927. Protective devices in spiders’ snares. Proc. Zool. Soc. Lond. 18 : 259-293. Levi, H.W. 1968. The spider genera Gea and Argiope in America (Araneae: Araneidae). Bull. Mus. Comp. Zool. Harvard 136: 319-352. _ 1978. Orb-weaving spiders and their webs. Sci. Amer. 66: 734-742. Lubin, Y.D. 1975. Stabilimenta and barrier webs in the orb webs of Argiope argenlala (Aranea, Araneidae) on Daphne and Santa Cruz Islands, Galapagos. J. Arach. 2 : 119-126. Marson, J.H. 1947. Some observations on the ecological variations and develop¬ ment of the cruciate zigzag camouflage device of Argiope pulchella (Thor.) Proc. Zool. Soc. Lond. 117 : 219-227. Robinson, M.H. and B. Robinson. 1970. The stabilimentum of the orb web spider, Argiope argentata: an improbable defence against predators. Canad. Ento- mol. 102 : 641-655. _ 1973. The stabilimenta of Nephila clavipes and the origins of stabilimen- tum-building in araneids. Psyche 80: 277-288. Steel, R.G.D. and J.H. Torrie, 1976. Introduction to Statistics. McGraw-Hill Book Company. Tolbert, W.W. 1975. Predator avoidance behavior and web defensive structures in the orb weavers Argiope aurantia and Argiope trifasciata (Araneae, Araneidae). Psyche 82 : 29-52. NESTING BIOLOGY OF OXYBELUS SERICEUS WITH A DISCUSSION OF NEST GUARDING BY MALE SPHECID WASPS (HYMENOPTERA) By Allan W. Hook 1 and Robert W. Matthews Department of Entomology University of Georgia Introduction Among sphecid wasps males are regularly associated with nesting females only in a few species. A review of territorial behavior in male sphecids (Alcock, 1975) has shown that such behavior is typically associated with obtaining copulations. Only rarely do males actively participate in nest maintenance or prey manipulation. Species of Oxybelus digger wasps show an unusual diversity of male behavioral adaptations. Several species display male nest guarding behavior, that is, a male defends a territory at sites of active nests and attempts to mate with the nesting female (Peckham et al., 1973; Peckham, 1977). Females exhibit an unusual prey carriage (impalement on the sting), and provision nests in exposed substrate ‘with paralyzed Diptera. Oxybelus sericeus is distributed throughout the United States and into Mexico (Bohart and Schlinger, 1957) and has been studied briefly by Bohart and Marsh (1960), who reported nest guarding. Here we present results of a two year study of the biology and behavior of O. sericeus in Georgia and discuss the phenomenon of nest guarding in sphecid wasps. Methods Observations were conducted during 5 August to 15 September 1977 and 12 May to 12 June, 7 to 10 September, 7 to 9 October 1978 on St. Catherine’s Island, 30 miles south of Savannah, Georgia at five separate study sites. Three beach sites were used primarily in 1977. The sparse dune vegetation consisted primarily of sandspur ( Cenchrus sp.) navelwort ( Hydroctyl bonariensis Lam), and Croton punctatus Jacq. Air temperatures ranged between 32° and 40° C during May to 'Present address: Department of Zoology and Entomology, Colorado State State University, FortCollins, Colorado 80523. Manuscript received by the editor June 6, 1980. 21 22 Psyche [Vol. 87 September. In 1978 the Boiler site (see Fig. 5 in Matthews et al., 1979) was mainly used. Observations were made from 0800 to 1800 on most days. Notes were taken in the field, supplemented with motion pictures of mating. Cell contents from nest excavations were transferred to sand-filled tins for rearing at room temperatures. Male observations used distinctively marked individuals and were mostly carried out at the Boiler site. Results Activity Periods and Development. Oxybelus sericeus is a multi voltine species that first emerged in May and continued to nest into October. Rearing data revealed that both sexes required about 26 days (25 to 27 males, n=7; 26 to 27 females, n=5) to develop from hatched egg to an emerged adult. Males appeared first in the morning (0830 to 0930) about 15 to 30 minutes before females. After females ceased provisioning males dug sleeping burrows between 1700 to 1900, 2 to 3 cm deep in the nest area. Nest Construction and Architecture. Nests were typically dug in exposed sand, but some females constructed nests under washed-up Spartina or shells. Nest structure is essentially the same as that of O. subulatus Robertson (Peckham et al., 1973). The only difference was the absence of a tumulus about O. subulatus nests because of its carrier-type digging behavior. Nest digging in O. sericeus was initiated by biting the surface and pushing back the loosened sand with the legs. As the burrow deepened sand was apparently gathered between the venter and hind legs and pushed up the vertical burrow, forming a tumulus. Tumuli were leveled after digging was completed and ranged 2 to 5 cm in diameter. Leveling consisted of females repeatedly raking sand 1 to 3 cm away in all directions from the perimeter of the entrance, and returning to the entrance. In multicellular nests filler sand for the completed cell was obtained from the nest side burrow and cell excavation. Excess sand was brought to the surface, forming a tumulus which was subsequently leveled. After leveling, females began “orientation” flights, meandering paths 1 to 5 cm above the nest area, which lasted 2 to 5 min. and covered lm 2 surrounding the nest. Cell depths averaged 7.9 cm (3.5 to 15, n=182). Cell dimensions varied, averaging 16.8 mm (8 to 24, n=97) long and 5.6 mm (4 to 7, n=99) wide. An average of 1.7 cells was present per nest (range, 55% 1980] Hook & Matthews — Biology of Oxebelus 23 had 1 cell and 0.9% had 6 cells). Final closure is similar to that reported for other Oxybelus (Peckham et al., 1973) and this process took 35.5 min (15 to 45, n=15). Ten nests made by one female had from 1 to 6 cells per nest. Females often constructed series of nests in localized areas (ave. distance between 9 nests by 1 marked female was 10.9 cm, range 1.5 to 26 cm). One female was found nesting 400 m across salt marsh from its original nesting area. Intraspecific nest usurpation was observed once. Provisioning and Prey Carriage. The mean duration between provisioning trips was 7.2 min. (1 to 140, n=163) with interruptions for mating included. Provisioning was most frequent between 1000 to 1700. Once a cell was full the female plugged the entrance from within the nest for oviposition and prey arrangement. Wasps provisioned up to three cells per day. Ninety-six percent of the prey from 149 completed cells consisted of three species of Diptera (Table 1). Cells averaged 7 flies per cell (3 to 14, n= 152); prey arrangement and egg placement may be classified as Crabro-style (Iwata, 1942). Oxybelus sericeus females transported prey from salt marsh to the nest area using pedal type 1 carriage (Evans, 1962), using their legs to grasp the prey. Once alighted near the nest (5-100+ cm from the nest, termed the “initial landing site” in Peckham etal., 1973)afemaletook a few seconds to face in the general nest direction. At this point she either impaled the prey on the sting (Fig. 1) or continued to carry the prey pedally as she crawled and/or flew the remaining distance to the nest. Some females only used pedal carriage as they transported prey entirely in flight, omitted the initial landing site and dropped into the open entrance (only very small flies were carried in this manner, see below). Most Oxybelus transport prey from the point of capture to the nest area using pedal carriage (i.e. bipunctatus and uniglumis, Peckham and Hook, in press). Prey is then impaled and the nest entered. Oxybelus sericeus differs from the others in that females may enter the nest using either pedal or impalement carriage. Our observations suggest that prey size influences the type of prey carriage used. Large, bulky prey normally elicited impalement carriage while small, less cumbersome prey were carried pedally. Prey weight corroborates this (Table 1). Ephydrids and some otitids averaged the least in weight and were rarely observed impaled, while dolichopodids averaged the heaviest and were usually impaled. Impalement carriage allows large 24 Psyche [Vol. 87 prey to be dragged, attached by the sting, enabling more efficient ground transport (the sting is impaled through a forecoxial corium, Steiner, 1979). Other factors may elicit impalement carriage. After copulation many females impaled (whether the prey was held pedally or impaled before copulation) and then entered their nests. Impaling under these conditions may speed up prey transport, minimizing further interruptions by males. Mortality. Cleptoparasitic miltogrammine flies (Sarcophagidae) were regularly present at all sites, with the genera Senotainia and Metopia predominant. Miltogrammine maggots were found in 14.5% (n=75) of the cells excavated at the beach sites, but the Boiler site had only 3.7% (n=107). Senotainia flies were attracted to males, females and mating pairs. Flies often hovered or perched behind copulating pairs though larviposition was not observed. Most flies followed the male after separation, enabling the female to provision safely. One beach site had 13.5% cell mortality due to the ant Solenopsis pergandi Forel (Formicidae). This ant appeared to rob cells while Figure 1. A female O. sericeus with a fly (Chaetopsis aenea) impaled on her sting. Nest entrance is at left. 1980] Hook & Matthews — Biology of Oxebelus 25 Table 1. Prey weights for most abundant prey captured by Oxybelus sericeus and a summary of 903 prey records from St. Catherine’s Island, Georgia. Weights are from frozen and subsequently thawed prey and are presumably slightly less than fresh weight due to dehydration. Species Number recorded from all nests % Average weight (mg) Range Sample size OTITIDAE Chaetopsis apicalis Johnson 209 21.3 0.34 0.13-0.59 103 Chaetopsis aenea (Wiedemann) DOLICHOPODIDAE 482 38.1 0.65 0.28-1.18 184 Nanomyina litorea Robinson The remaining 4% of the prey consisted of: 184 36.6 0.9 0.34-1.64 177 DOLICHOPODIDAE Paraclius sp. (1) Paraclius hybridus Melander (2) Paraclius filifer Aldrich (1) Thinophilis sp. (1) Thinophilis frontalis Van Duzee (5) Pelasloneurus sp. (2) Hypocharassus gladiator Mik (4) Hypocharassus pruinosus (Wheeler) (2) EPHYDR1DAE Notiphila bispinosa Cresson (1) Lipochaeta solossonae Cresson (1) Polytrichophora conciliata Cresson (1) Cirrula fuscifemur (Steyskal) (7) tunneling below the surface. On three occasions, Conomyrma ants discovered active nests at the Boiler site and removed prey after recruitment of additional workers. Conomyrma ants were able to locate nests even after final closure. When excavating a completed nest, workers removed sand from the burrow until a stocked cell was reached. Mold accounted for 36% (n=33) cell mortality at the Boiler site (sometimes high tides covered this site). Male Reproductive Strategies. Once a female began to nest, a male became closely associated with that nest as long as the female actively provisioned. Males perched near the entrance, either on the sand or a raised object (Fig. 2). Periodically the male changed positions, confining its activity to within 0.5 m of the nest. Guarding males often entered nests, particularly if females were late in returning, and sometimes stationed themselves head-out in the entrance, a guarding position typically used by O. subulatus (Peckham, 1977 and pers. obs.). Territories encompassed an area approximately 1 m in diameter surrounding the nest entrance. Males chased all 26 Psyche [Vol. 87 Figure 2. A guarding male of O. sericeus perched on a nest marker nail adjacent to an active nest. intruding insects, especially rival males, and permitted only females to approach. Each time the female returned to or left the nest the guarding male attempted to mount. During copulation, the mounted male faced the same direction as the female, and used his middle legs to grasp the female’s wings. The male’s front legs were drawn in with the tarsi touching the female’s pronotum and the hind legs helping to support her gaster (Fig. 3). During copulation males alternate between biting the female’s vertex and cervical region and antennating her antennae or frons. Some males were observed to copulate over twenty times per day, with a gradual decline in the copulation duration from about 2 min. to about 10 sec. After a female completed provisioning and plugged her entrance from within, the guarding male tended to patrol further from the nest, returning to inspect it intermittently. Such males usually took up defense of any unguarded nests they could locate. Presence of the male was not a prerequisite for provisioning; females nested whether or not a male guarded their nest. Alternative to guarding of active nests we identified three other apparent male strategies: patrolling, guarding of the initial landing 1980] Hook & Matthews — Biology of Oxebelus 27 Figure 3. Copulation in O. sericeus. The male is dorsal and grasps the female’s wings with his middle legs while antennating her frons. The female’s prey (Nanomvina litorea) has been temporarily dropped to permit copulation. site and guarding lost prey. Patrolling consisted of cruising low (5 cm above ground) throughout the nest area without associating with particular nests. Males commonly used this behavior when searching for active nests to guard or exposed females. At times females provisioned infrequently, causing the majority of males to adopt the patrolling strategy. Guarding the initial landing site was possible because, as mentioned, prey-laden females typically land away from the nest and then proceed to enter. On five occasions a male ceased nest guarding and instead took up defense of a territory about the initial landing site. Two conditions seemed prerequisite to this strategy: first, intense male competition for the nest territory; second, a propensity by the female to land repeatedly in the same area prior to entry. On ten occasions prey were abandoned by females when intensively interfered with by one or more males. When this occurred, males perched next to the prey, chased off intruding males and copulated with the female if she returned. Male-Male Competition. It became apparent during the 1977 season that there was considerable individual variation in the number 28 Psyche [Vol. 87 of copulations obtained and that individual males were not limited to a single mating strategy. At the Boiler site we followed interactions between marked individuals daily for 22 days (15 May to 5 June). Of 51 males marked, 13 were observed an average of7.5 days (5 to 13), 29 for 1 to 3 days and 9 were marked the last three days of the study. In addition to clarifying male mating strategies these data revealed that individual males differed greatly in their success in acquiring and defending nest territories. Usually 5 to 12 males actively competed for territories and matings each day. Though the composition of males changed daily as new wasps emerged and marked ones disappeared, three males dominated our data. These “dominant” males won most encounters and thus were rarely forced to abandon a nest territory when challenged. Moreover, the “dominant” males quickly abandoned inactive nests and patrolled until they located an unguarded or (more likely) a guarded nest. Violent, aggressive interactions (Fig. 4) occurred between nearly equal size males competing for the same nest. An intruding male flew directly at the guard, and a fierce grappling match resulted, lasting from several seconds to over one minute. Often a series of grappling matches took place before one male retreated. “Dominant” males frequently usurped nest territories from other guarding males; one male usurped 15 territories in four days. Females displayed no obvious behavioral change when new males took over their nest territory. We believe that the isolation and relatively small size of the Boiler site area (7.6 X 2.4 m) enabled individual males to establish and maintain their dominance. One male won all encounters over a seven-day period and another male was completely dominant over a different four-day period. Female Receptivity. Upon eclosion females were sexually recep¬ tive, allowing males to copulate for 2 to 3 minutes (x=2.5, n=4), after which males dismounted. When mounted a female submitted quickly by raising her gaster, allowing copulation. Newly emerged females required a few days to develop mature eggs (dissections of newly eclosed wasps revealed small, clear eggs beginning to develop in the ovarioles). These females spent considerable time investigating the nesting area and were therefore easy targets for patrolling males. Once nesting began, females tended to avoid males when digging or provisioning. When intercepted, females varied in their response; some allowed a male to mate on most trips to the nest without 1980] Hook & Matthews — Biology of Oxebelus 29 Figure 4. A pair of O. sericeus males grappling to determine territory ownership. struggling, while others more strongly resisted male advances. Resistance consisted of bending the gaster down and pygidium forwards, or dragging the mounted male and prey towards the entrance. Females appeared to initiate the termination of copulation by struggling, thereby inducing the male to dismount, although persistent males at times ignored such signals. Provisioning females mainly interacted with guarding males, but sometimes they were mounted by as many as four different males between the initial landing site and their burrow. Rarely a female dragged a mounted male and prey to the nest entrance, and squeezed past him into the burrow without permitting copulation. More commonly, male and prey were too cumbersome to transport (especially if over 50 cm from the nest); in this situation prey-laden females more readily submitted. 30 Psyche [Vol. 87 Discussion The most efficient strategy for O. sericeus females appears to be to allow males to copulate, thereby minimizing the total energy and time spent in the interaction. The size of the nest area, density of nests, and the operational sex ratio probably greatly influence the quantity and intensity of male-female interactions. In order to better understand possible selective forces acting to bring about nest guarding in Oxybelus, comparison will be made with other nest guarding sphecids (Table 2). Wasps that have males associated with the parental nest (e.g. Microstigmus, Philanthus and Cerceris) are excluded here, but twig, cavity and mud nesters are included in Table 2 mainly to suggest that such interesting wasps deserve further study. Males in some species cue in on provisioning females. These males patrol and also perch next to active nests, though not associating with any particular nest. For this to evolve requires that females remain receptive throughout the nesting cycle. For a male the advantage would be in the increased probability of his sperm fertilizing the egg, assuming sperm precedence which is well documented in other insects (see Lefevre and Jonsson, 1962; Boorman and Parker, 1976; Smith, 1979). Gillaspy (1962) found males of Sphex trepanecus Saussure to cue in on provisioning females. When a prey-laden female approached her nest a male would appear and copulation occurred near the nest. The crabronine genus Lindenius commonly has males searching and entering nest entrances and Miller and Kurczewski (1973) hypothesized that such “nest searching” behavior may help reduce cleptoparasitism (by miltogrammine flies and chrysidid wasps) in dense aggregations. Oxybelus emarginatus normally has males patrolling nest areas but Krombein (1964) once found males in Florida not only patrolling and perching but also mounting and copulating with provisioning females. One of us (AWH) recently briefly observed the same behavior in O. emarginatus near Mission, Texas, only no copulations were observed. This ability to cue in on provisioning females probably developed early in the evolution of nest guarding. The transition from the ability to intercept provisioning females to establishment of territories in the nesting area seems a logical step. In Sphex cognatus Smith (Ribi and Ribi, 1980) and Tachysphex species (Kurczewski, 1966) males are known to maintain territorial stations in nesting areas and copulate with nesting females. In several other species male territories always include at least one female nest. These 1980] Hook & Matthews — Biology of Oxebelus 31 include Oxybelus subulatus (Peckham, 1977), Stizus (Megastizus) texanus Cresson (Gillaspy, unpubl.) and Tachytes distinctus Smith (Lin, 1963; Lin and Michener, 1972). Stizus texanus nested near Matomoros, Mexico and males defended nest territories, copulating with provisioning females. Tachytes distinctus defended nest territories but did not attempt to mate with provisioning females. Research on Trypargilum suggests that male guarding helps reduce cleptoparasitism and supersedure by other wasps and bees (Krombein, 1980). Males may also assist in nesting activities and females of at least one species will not provision unless a guard is present (Coville and Coville, 1980). Peckham (1977) provides quantitative data on the effect of male O. subulatus in reducing miltogrammine cleptoparasitism. Unguarded nests had 33% (examined 85 cells) cleptoparasitism while guarded nests had only 18%(n=84). “Thus the presence ofthe male appears to have significantly reduced miltogrammine cleptoparasitism.” The low rate of cleptoparasitism in O. sericeus at the Boiler site can be taken as indirect evidence that guards in this species reduce cleptoparasitism. Earlier stages in the evolution of nest guarding as found in Oxybelus sericeus may be found in other Oxybelus. Several Oxybelus ( bipunctatus, subcornutus Cockerell, emarginatus, Peckham et al., 1973 and pers. obs.; decorosus, uniglumis, Peckham and Hook, in press) fit this pattern whereby males patrol the nest area, indiscrimi- nantly chasing nearby moving insects. Peckham et al. (1973) found only 6% fly cleptoparasitism in an aggregation of O. bipunctatus, and attributed this low figure partially to male harassment of miltogram¬ mine flies. In summary, we suggest the following scenerio for the evolution of nest guarding in sphecid wasps. Initially males cue in on females who are actively provisioning nests and who remain continuously receptive to copulation attempts. Under certain ecological conditions the benefits resulting from defense of an area (territory) within a nest aggregation will exceed the costs to males. Sperm precedence may be an important factor in this context, if it occurs, for the last male to inseminate a female prior to oviposition will have increased fitness relative to other males. An incidental but important effect of the male’s presence and activity is to reduce levels of cleptoparasitism (and perhaps supercedure) thereby improving a female’s nesting success relative to females inseminated by non-territorial males. It 32 Psyche [Vol. 87 x: o CQ £ -TD < £ •g « H S c c T3 *o cx 5* £ « *o *o £ 2° O' vo S~2i ~ •O ^ S &.S s-*s .§ £ a a ^WOC^ <U <D <L> <U § 5 g •S’ a - -s £ „ . — ON • ~ c U 2 - ON O *« •§ , m r-- ►- 1 c 5 •-* on O' . „ O cx 'O .y 3 ^ aj •— OV O . U T3 -^ - ~. s ^ 5 S 3 - e ■? o a « S a j 3 I ^ 2 H sl •5 So c bo O •S5 S’ §■- - I 8 2 .bo ^ -s; • r? A A C-1 Co C<5 C c •5 o c td t « . E .5 S w Ou l I I »l I I ill -§ p * s ^ VO ' ON O ^ (U CU <U — 0^ N „ « <U C E ea -53 fl D- £ J= . „ c iSg g £2^ cj oo r-' O M VO a. on on c c >. S S’ ^3 C <3 X o cx =3 e as "t: _> 4J £X XJ do" I on 2 22 £ 3 c 2 *» ^ i- Si & ^ if 'So .g ‘So o JC“ O A o 3 ^3 -a "S -s o A, A, 2 A, O S S £ =\ JS -A 3 ft t A c a x~ Si Si A, ft ft 2 ft $ attempts <3 associates to mate w/ $ deters $ assists w/individual 2 at or clepto- in nesting Subfamily, tribe Species nest near nest parasites activities Source Trypargilum texense yes — — — Hartman, 1905 34 Psyche [Vol. 87 would be further enhanced if males focused their territorial activity around active nests. If females exercise a preference for presence of a guarding male prior to initiating nesting (e.g. Trypargilum), then this behavior would spread in the population, since it would directly benefit the interests of both sexes. The possibility exists that males could ultimately be induced to guard nests without requiring repeated matings as is reported for Tachytes distinctus (Lin, 1963; Lin and Michener, 1972). However, such cases are in need of further study. In digger wasps, delays in provisioning and exposure to predators and cleptoparasites constitute important risks for females; but rejection of males may be costly in terms of time, energy and loss of resource (the nest). Such costs to the female must be important, otherwise females of O. sericeus would not often attempt to sneak past guarding males when provisioning. Guarding males also incur real costs in addition to time and energy expenses. Gwynne and O’Neill (1980) recently showed that territoriality in Philanthus males resulted in increased mortality due to sex-biased predation. In Oxybelus sericeus the balance struck appears to effect a significant reduction in levels of cleptoparasitism, so male guarding directly benefits the interests of both sexes. Summary The multivoltine wasp Oxybelus sericeus nested continually from early May to October on St. Catherine’s Island, Georgia. Nest sites were situated in sand just above a tidal salt marsh where the females hunted prey. Two otitid flies, Chaetopsis apicalis and C. aenea and one dolichopodid, Nanomyina litorea, comprised 96% of the prey. Up to three cells per day were stocked with an average of 7 (range 3 to 14) flies per cell. Prey were transported pedally from point of capture to the nest area whereupon females either continued pedal transport or impaled the fly on the sting before continuing to the nest. Number of cells per nest averaged 1.7 (range 1 to 6) with individual females varying the number of cells in successive nests. Cell depths averaged 7.9 cm (range 3.5 to 15). Males were active in the nest area and utilized five different mating strategies. Patrolling and nest guarding were the most common strategies. Certain individuals were found to dominate all other males in encounters in a small nesting area. These dominant males shifted their guarding activities to “track” actively nesting females for up to seven days. Miltogrammine fly parasitism ranged 1980] Hook & Matthews — Biology of Oxebelus 35 from 3.7% to 14.5%; Senotainia sp. was the predominant parasite, but Metopia sp. was also recorded. Ants {Solenopsispergandei Forel and Conomyrma sp.) were nest predators, with 13.5% cell mortality due to Solenopsis recorded at one site. Records of male association with nesting females are summarized from the literature. The idea is developed that the effect of a male’s presence and activity in reducing mortality from cleptoparasitism supersedure has been an important factor in the evolution of male nest guarding and female’s toleration of interference due to repeated copulation attempts. Acknowledgements This work was supported by a grant awarded to R. W. Matthews by the Edward John Noble Foundation in conjunction with the American Museum of Natural History. Special thanks to J. T. Woods and staff for their support on the island: J. E. Gillaspy for the use of unpublished information; R. J. Gagne, L. Knutson, W. N. Mathis, G. C. Steyskal, F. C. Thompson, A. S. Menke and D. R. Smith of the I.I.I.P.I., USDA, for determination of prey specimens, cleptoparasitic flies, wasps and ants. R. M. Bohart of the University of California at Davis assisted in wasp determinations. J. W. Krispyn helped with the field work and preparation of the manuscript and D. J. Peckham and G. C. Eickwort critically reviewed the manuscript. Literature Cited Alcock, J. 1975. Territorial behaviour by males of Philanthus multimaculatus (Hymenop- tera: Specidae) with a review of territoriality in male sphecids. Anim. Behav. 23:889-895. Bohart, R. M., and P. M. Marsh 1960. Observations on the habits of Oxybelus sericeum Robertson (Hymenop- tera: Sphecidae). Pan-Pac. Ent. 36:115-118. Bohart, R.M., and A.S. Menke 1976. Sphecid Wasps of the World: A generic revision. Berkeley, Calif.: University of California Press, 695 pp. Bohart, R. M., and E. I. Schlinger 1957. California wasps of the genus Oxybelus (Hymenoptera: Sphecidae, Crabroninae). Bull. Calif. Insect Surv. 4:103-143. Boorman, E., and G. A. Parker 1976. Sperm (ejaculate) competition in Drosophila melanogasier. and the reproductive value of females to males in relation to age and mating status. Ecol. Ent. 1: 145-155. 36 Psyche [Vol. 87 Coville, R. E. 1979. Biological observations on Trypoxylon (Trypargilum) orizabense Richards in Arizona (Hymenoptera: Sphecidae). J. Kans. Ent. Soc. 52:613-620. Coville, R. E., and P. L. Coville 1980. Nesting biology and male behavior of Trypoxylon (Trypargilum) tenoctit- lan in Costa Rica (Hymenoptera: Sphecidae). Ann. Ent. Soc. Amer. 73:110-119. Eberhard, W. T. 1974. The natural history and behavior of the wasp Trigonopsis cameronii Kohl (Sphecidae). Trans. R. Ent. Soc. Lond. 125:295-328. Evans, H. E. 1962. The evolution of prey-carrying mechanisms in wasps. Evolution 26:468- 483. Fattig, P. W. 1936. Nesting building of Trypoxylon politiforme Roh. Can. Ent. 68:44-45. Gillaspy, J. E. 1962. Nesting behavior of Sphex trepanecus Saussure (Hymenoptera: Sphecidae). Bull. Brooklyn Ent. Soc. 57:15-17. GWynne, D. T., and K. M. O’Neill. 1980. Territoriality in digger wasps results in sex-biased predation on males (Hymenoptera: Sphecidae, Philanthus). J. Kans. Ent. Soc. 53:220-224. Hartman, C. 1905. Observations on the habits of some solitary wasps of Texas. Bull. Univ. Texas. 65:1-73. Iwata, K. 1942. Comparative studies on the habits of solitary wasps. Tenthredo 4:1-142. Kimsey, L. S. 1978. Nesting and male behavior in Dynatus nigripes spinolae (Lepeletier) (Hymenoptera: Sphecidae). Pan-Pac. Ent. 54:65-68. Krombein, K. V. 1958. Miscellanaeous prey records of solitary wasps. III. (Hymenoptera, Aculeata). Proc. Biol. Soc. Wash. 71:21-26. 1964. Results of the Archbold expeditions. No. 87. Biological notes on some Floridean wasps. (Hymenoptera, Aculeata). Amer. Mus. Novitates 2201:1-27. 1967. Trap-nesting Wasps and Bees: Life Histories, Nests and Associates. Smithsonian Press, Washington, D. C. 570 pp. 1980. Catalog of Hymenoptera in America North of Mexico. Vol. 2, 1645 pp. Kurczewski, F. E. 1966. Comparative behavior of male digger wasps of the genus Tachysphex (Hymenoptera: Sphecidae, Larrinae). J. Kans. Ent. Soc. 39:436-453. Lefevre, G., and U. B. Jonsson 1962. Sperm transfer, storage, displacement, and utilization in Drosophila melanogaster. Genetics, Princeton 47:1719-1736. Lin, C. S. 1979. Biology of Trypargilum spinosum, with notes on T. texense and T. politum at Lake Texoma (Hymenoptera: Sphecidae; Trypoxyloninae). Wasmann J. Biol. 27:125-133. 1980] Hook & Matthews — Biology of Oxebelus 37 Lin, N. 1963. Territorial behavior of the cicada killer wasp, Sphecius speciosus (Dury) (Hymenoptera: Sphecidae). I. Behavior 20:115-133. Lin, N., and C. D. Michener 1972. Evolution of sociality in insects. Quart. Rev. Biol. 47:131-159. Masuda, H. 1939. Biological notes on Pison iwatai Yasuraatsu. Mushi 12:114-146. Matthews, R. W., A. Hook, and J. W. Krispyn 1979. Nesting Behavior of Crabro argusinus and C. hilaris (Hymenoptera: Specidae). Psyche 86:149-166. Miller, R. C., and F. E. Kurczewski 1973. Intraspecific interactions in aggregations of Lindenius (Hymenoptera: Specidae, Crabroninae). Insectes Sociaux 20:365-378. Minkiewicz, R. 1934. Les types de comportement des males de Sphegiens. Polskie Pismo Ent. 13:1-20. Paetzel, M. M. 1973. Behavior of the male Trypoxylon rubrocinctum. Pan-Pac. Entomol. 49:26-30. Peckham, G. W., and E. G. Peckham 1898. On the instincts and habits of the solitary wasps. Wisconsin Geol. Nat. Hist. Survey, Sci. Ser., Bull. No. 2, 245 pp. Peckham, D. J., F. E. Kurczewski, and D. B. Peckham 1973. Nesting behavior of Nearctic species of Oxvbelus (Hymenoptera: Spheci¬ dae). Ann. Ent. Soc. Amer. 66:647-661. Peckham, D. J. 1977. Reduction of miltogrammine cleptoparasitism by male Oxybelus subula- tus (Hymenoptera: Sphecidae). Ann. Ent. Soc. Amer. 70:823-828. Peckham, D. J., and A. W. Hook 1980. Behavioral observations on southeastern Oxybelus (Hymenoptera: Sphe¬ cidae). Ann. Ent. Soc. Amer. (In press) Rau, P. 1928. Field studies in the behavior of the non-social wasps. Trans. Acad. Sci. St. Louis 25:325-489. 1933. The Jungle Bees and Wasps of Barro Colorado Island. Phil Rau, Kirkwood, Mo. 317 pp. Ribi, W. A., and L. Ribi 1979. Natural history of the Australian digger wasp Sphex cognatus Smith (Hymenoptera: Sphecidae). J. Nat. Hist. 13:693-701. Smith, R. L. 1979. Repeated copulation and sperm precedence: paternity assurance for a male brooding water bug. Science 205:1029-1031. Steiner, A. L. 1979. Digger wasp predatory behavior (Hymenoptera: Sphecidae): fly hunting and capture by Oxybelus uniglumis (Crabroninae: Oxybelini); a case of extremely concentrated stinging pattern and prey nervous system. Can. J. Zool. 57:953-962. Tsuneki, K. 1970. Gleanings on the bionomics of the East-Asiatic non-social wasps. VI. Some species of Trypoxyloninae. Etizenia 45:1-20. ECOLOGICAL LIFE HISTORY OF BAETISCA BERNERI TARTER AND KIRCHNER FROM A WEST VIRGINIA STREAM (EPHEMEROPTERA: BAETISCIDAE) By William R. Morris, Dwight L. Chaffee and Donald C. Tarter 1 The primary objective of this investigation was to study the ecological life history of the mayfly Baetisca berneri Tarter and Kirchner in Laurel Fork, Mingo Co., West Virginia. Many authors, including Say (1839), Traver (1931), Needham et al. (1935), Berner (1940, 1955), Edmunds (1960), Schneider and Berner (1963), Pescador and Peters (1971, 1974), Lehmkuhl (1972), Tarter and Kirchner (1978) and Chaffee and Tarter (1979), have reported studies on the taxonomy and ecology of the genus Baetisca. Taxonomy and Distribution The genus Baetisca, established by Walsh (1862), is the only member of the family Baetiscidae. Presently, there are 12 species of Baetisca known from the United States (Edmunds et al., 1976; Tarter and Kirchner, 1978). Tarter and Kirchner (1978) described the new species B. berneri and reported its distribution from West Virginia and Virginia. Materials and Methods The study site is Laurel Fork of Pigeon Creek of Tug Fork of the Big Sandy River in Mingo County, West Virginia. It lies 2.4 km southeast of Dingess and 3.2 km northeast of Laurel Lake. The stream width averages 4.6 m and the water depth ranged from 2.5 to 74 cm. The substrate is sand, gravel and rocks. The more dominant species of the riparian forest are Red Maple, Acer rubrum L.; Smooth Alder, Alnus serrulata (Ait.) Willd.: Black Birch, Betula lenta L.; Rhododendron, Rhododendron maimum L.; and Eastern Hemlock, Tsuga canadensis (L.) Carr. 'Dept, of Biological Sciences, Marshall Univ., Huntington, W. Va. 25701 Manuscript received by the editor August 13, 1980. 39 40 Psyche [Vol. 87 Monthly samples of nymphs were taken from December, 1974, to November, 1975. The bottom substrate was disturbed and a hand dredge (mesh size, 0.75 mm 2 ) was placed directly downstream to collect the drifting nymphs. Except for the rearing experiment, all nymphs were preserved in 70 percent ethanol. The water quality parameters were measured monthly throughout the study period with a Hach kit, Model AL-36-WR. Dissolved oxygen (mg/1), carbon dioxide (mg/1), bicarbonate alkalinity (mg/1 CaC0 3 ), total hardness (mg/1 CaC0 3 ) and pH were recorded. Water temperature was measured each month with a Taylor thermometer placed near the surface of the water. Length-frequency distributions were recorded for the nymphs in order to help determine the duration of the life cycle. The body length (from the base of the caudal filaments to the front margin of the head excluding the genal spines) was measured under a Bausch and Lomb dissecting microscope with a Vernier caliper to the nearest 0.1 mm. Both sexes were grouped together and placed in one millimeter size groups. A population range diagram was used to show the monthly variation in nymphal head widths. The head width measurements, excluding the eyes, were made with an ocular micrometer mounted in a dissecting microscope to the nearest 0.05 mm. Males and females for each month were separated and the range, mean, standard deviation and standard error of the mean were calculated for each group. Sex determination of the nymphs was made by the position and shape of the eyes. The eyes of the male were closer together and more angular toward each other than those of the female. A chi-square test was applied to determine any significant departure from the expected 1:1 ratio at the 0.05 confidence level. The foregut content of five nymphs was analyzed for each month. The head was severed from the body with micro-dissecting scissors and an incision was made along the midline of the ventral body surface to the center of the abdomen. The foregut was removed and its contents emptied onto a microscope slide with water as the' mounting medium. The contents were viewed under a microscope with a Whipple ocular grid at 430X magnification. Ten fields or grids were selected at random and counted for each nymph. Values were given according to the number of small grid squares covered by the individual food item. Organic and mineral detritus were grouped 1980] Morris, Chaffee, & Tarter — Baetisca 41 together. Diatoms and filamentous algae were grouped as separate catgories. A habitat preference study on nymphs was designed. A tray (61 X 30.5 X 6.5 cm) was filled with 2.5 cm of water from the study area. The bottom of the tray was filled with three different substrates. One- third was filled with sand only, one-third with sand, gravel and small rocks and one-third with sand and leaf litter. The water was constantly aerated with a Hush air pump and the tray was placed in a controlled chamber which kept the water temperature at 11 C. The nymphs were then released at different places in the tray. After 12 hours of darkness, the tray was checked for the location of the nymphs. The entire tray was then illuminated with a light placed so that it shone equally on each area. After 12 hours, the nymphal positions were checked. The second part of the experiment involved shining the light directly on one area, while the other two areas were covered. After 12 hours, the position of the nymphs was recorded and another area was illuminated. The entire experiment was then replicated. Direct egg counts of four subimagos and three imagos from lab rearings were made. These adults had been preserved in 70 percent ethanol. The body cavity was opened with micro-dissecting scissors and the eggs were carefully extruded into a culture dish and counted under a Bausch and Lomb dissecting microscope. The diameter of 50 eggs per female was measured with an ocular micrometer mounted in a microscope to the nearest 0.01 mm. Results and Discussion Stream Environment.—The water quality of Laurel Fork was excellent for aquatic life. Dissolved oxygen concentrations ranged from 10 (June-August) to 14 mg/1 (February and April); the mean was 11.9 mg/1. Carbon dioxide was 5 mg/1 during all months except November (10 mg/1). Total hardness ranged from 34.2 mg/1 in February, March and October to 68.4 mg/1 in May and June; the mean was 49.7 mg/1. Bicarbonate alkalinity values ranged from 13.7 to 51.3 mg/1. February and May-September, respectively; the mean was 37.6 mg/1. The hydrogen ion concentration (pH) ranged from 7.5 to 8.5; the mean was 8.1. The mean annual water temperature was 11.6 C; the range was 2.8 to 22.0 C, January and August, respectively. 42 Psyche [Vol. 87 E E E E E E E rTEm 3 4 5 6 7 8 BODY LENGTH, * 10 11 12 MM Figure 1. Size-class distribution of nymphs of Baetisca berneri based on body length. The number of individuals each month is in parenthesis. 1980] Morris, Chaffee, & Tarter — Baetisca 43 NYMPHAL STAGE Size-Class Distribution. —Length-frequency distributions indicate a univoltine life cycle (Figure 1). The smallest nymph (2.1 mm) was collected in July and the largest nymph (11.2 mm) was taken in May. The increasing monthly progression of the size class and the total disappearance of large nymphs in the July sample indicated a one year life cycle. Nymphs hatched as early as July and progressed in size until late May or June when they emerged. Numerous nymphal skins were found on stones less than 5 cm from the waters edge or water lies in mid-June. The population range diagram, based on nymphal head widths, is presented in Figure 2. The smallest head width occurred in July (0.7 mm) and the largest head width occurred in May (3.1 mm). Traver (1931) collected Baetisca Carolina in North Carolina in March and emergence occurred in April and May in the laboratory. Small nymphs of B. callosa in West Virginia were found as early as August (Traver, 1931). Traver (1937) found skins of B. thomsenae (= Carolina) in Florida in May and June. Berner (1955) reported laboratory emergence of B. obesa from early March to early April in D JF'MUMjJISON MONTH Figure 2. Population range diagram of nymphs of B. berneri based on head widths. Vertical lines = range, horizontal lines = mean, open rectangles = one standard deviation, closed rectangles = one standard error of the mean, m = male, and f = female. 44 Psyche [Vol. 87 southern Georgia and northern Florida. Pescador and Peters (1971) found extremely small nymphs of B. becki in Florida in September and nymphs collected in April emerged in May in the laboratory. Chaffee and Tarter (1979), in studying the life history of B. bajkovi in West Virginia, reported a univoltine life cycle. The smallest nymphs were found in July with the largest nymphs collected in the middle of May. Emergence occurred in May. Lehmkuhl (1972) studied the life cycle of B. bajkovi in Canada and found a one year life cycle. Eggs hatched in early September and mature nymphs emerged in the laboratory in June and July. Pescador and Peters (1974) observed a one year life cycle for B. rogersi in Florida. Nymphs were first found in September and emerged from April to July. Berner (1955) reported a different account for B. escambiensis. He collected mature nymphs in October from a Florida river and they emerged in the laboratory in November. Sex Ratio. —The expected 1:1 sex ratio was observed for B. berneri. Ninety-seven males and 100 females were collected during the study period. The difference was not significant at the 0.05 confidence level. Foregut Analysis .—The foregut contents of the nymphs for the study period are given in Table 1. The main constituent was always detritus, with diatoms usually abundant, and filamentous algae present to a smaller degree. Most abundant diatoms were Synedra ' sp., Cymbella sp., Nitzschia sp., Navicula sp. and Gomphonema sp. Table 1. Relative abundance of foregut contents of Baetisca berneri nymphs from Laurel Fork, Mingo County, West Virginia. Filamentous Detritus Diatoms Algae No. of Month (%) (%) (%) Foreguts Sept. 88.0 8.0 4.0 5 Oct. 72.0 26.(1 2.0 5 Nov. 70.0 29.0 1.0 5 Dec. 64.0 35.0 1.0 5 Jan. 75.0 20.0 5.0 5 Feb. 87.0 10.0 3.0 5 Mar. 86.0 6.0 6.0 5 Apr. 68.0 30.0 2.0 5 May 53.0 36.0 11.0 5 June 80.0 19.0 1.0 2 Mean 74.5 22.0 3.5 47 1980] Morris, Chaffee, & Tarter — Baetisca 45 Other recognizable diatoms were Fragilaria sp., Meridion sp., Cocconeis sp. and Achnanthes sp. Diatom abundance was greatest during April and May and October-December. The nymphs collected during May had the largest amount of filamentous algae. One desmid was found in the study ( Straurastrum sp.). Pescador and Peters (1974) conducted a similar study on B. rogersi and the results corresponded with those in this study. However, it must be pointed out that their particles were counted on the basis of number present and not on the area of small grid squares covered. The nymphs of B. bajkovi are detritivorous with almost two-thirds (65.3%) of the diet composed of plant and leaf detritus (Chaffee and Tarter, 1979). Habitat Preference .—The preference was for the sand, gravel and small stone substrate during all light or all dark conditions. A slight preference for sand and leaf litter over sand only was shown. When the light was directed to one substrate only, the majority of nymphs moved to that substrate. Pescador and Peters (1974) reported similar results for B. rogersi. Lehmkuhl (1972) found that B. bajkovi preferred a stony or grassy substrate to a sand only substrate. ADULT STAGE Rearing Observations .—Nymphs were reared in the laboratory beginning April 23 and emerged from May 7 to the end of May. All subimagos emerged betwen 10 AM and 2 PM and all imagos emerged approximately 24 hours later. Emergence of B. bajkovi adults occurred in the laboratory from May 2 to May 26 (Chaffee and Tarter, 1979). All subimagos emerged betwen 9 AM and 7 PM with the imagos emerging 13 to 25 hours later. Emergence data for other members of the genus Baetisca were reported by Traver (1931 and 1937), Berner (1940 and 1955) and Pescador and Peters (1974) found that duration of the subimago stage of B. rogersi is dependent on water temperature. The warmer temperatures produce a shorter subimago stage. Fecundity .—Egg counts for B. berneri ranged from 1001 to 2375; the mean number of eggs per female was 1899. Egg counts were reported for B. rogersi (Pescador and Peters, 1974). The range was from 1500 to 2727 eggs; the mean number of eggs per individual was 2168. Ovarian egg counts for B. bajkovi ranged from 1508 to 3158; the mean was 2361 (Chaffee and Tarter, 1979). 46 Psyche [Vol. 87 Egg Size and Morphology. —The mean egg diameter was 0.18 mm; individual eggs ranged from 0.13 to 0.21 mm. The eggs were sculptured and mostly round, and were olive green in color. Smith (1935) reported the egg diameter of B. obesa and B. Carolina to be 0.18 mm and reported them to be nearly spherical and smooth on the surface. Pescador and Peters (1974) reported different sizes and shapes for newly laid eggs of B. rogersi and for eggs 3-5 hours after oviposition (mature eggs). Newly laid eggs which would correspond to those in this study were 0.1-0.2 mm in diameter, slightly oblong, and sculptured. The mature eggs were rounded, smooth and 0.2-0.3 mm in diameter. References Berner, L. 1940. Baetisca rogersi, a new mayfly from northern Florida. Can. Ent. 62:156-160. _ 1955. The southeastern species of Baetisca (Ephemeroptera: Baetiscidae). ' Quart. J. Fla. Acad. Sci. 18:1-19. Chaffee, D. L., and D. C. Tarter. 1979. Life history and ecology of Baetisca bajkovi Neave in Beech Fork of Twelvepole Creek, Wayne County, West Virginia (Ephemeroptera: Baetiscidae). Psyche 86(1):53-61. Edmunds, G. F. 1960. The mayfly genus Baetisca in western North America. Pan- Pacific Ent. 36(2): 102-104. _, S; L. Jensen, and L. Berner. 1976. The mayflies of North and Central America. Univ. of Minnesota Press, Minneapolis, Minn. 330 pp. Lehmkuhl, D. M. 1972. Baetisca (Ephemeroptera: Baetiscidae) from the western interior of Canada with notes on the life cycle. Can. J. Zool. 50(7); 1015—1017. Needham, J. G., J. R. Traver, and Y. FIsu. 1935. The Biology of Mayflies, Comstock Publishing Co., Inc., Ithaca, N. Y. 759 pp. Pescador, M. L., and W. L. Peters. 1971. The imago of Baetiscabecki Schneider and Berner. Fla. Ent. 54(4):329-334. _ 1974. The life history and ecology of Baetisca rogersi Berner (Ephemerop tera: Baetiscidae). Bull. Fla. State Mus. Biol. Sci. 17(3): 151 209. Say, T. 1839. Descriptions of new North American neuropterous insects and ob¬ servations on some already described. J. Acad, Nat. Sci. Phila. 8:9-46. Schneider, RT F., and L. Berner. 1963. A new southeastern species of Baetisca (Ephemeroptera: Baetiscidae). Fla. Ent. 46:183-187. Smith, O. R. 1935. Chapter VII. The eggs and egg-laying habits of North Ameri¬ can mayflies, pp. 67-89. In: Needham, J. G., J. R. Traver, and Y. Hsu. 1935. The Biology of Mayflies with a systematic account of North American Species. Com¬ stock Publ. Co., Inc., Ithaca, N. Y. 759 pp. Tarter, D. C., and R. F. Kirchner. 1978. A new species of Baetisca from West Virginia (Ephemeroptera: Baetiscidae). Ent. News 89(9— 10):209—213. Traver, J. R. 1931. The ephemerid genus Baetisca. J. N. Y. Ent. Soc. 39:45-66. _ 1937. Notes on mayflies of the southeastern United States. J. Eli. Mitch. Soc. 53:27-87. 1980] Morris, Chaffee, & Tarter — Baetisca 47 Walsh, B. D. 1862, List of Pseudoneuroptera of Illinois, contained in the cabinet of the writer, with description of over forty new species and notes of their struc¬ tural affinities. Proc. Acad. Nat. Sci. Phila. 13:361-402. MORPHOLOGY OF THE STERNAL GLANDS OF POLISTES FUSCA TUS AND P. CANADENSIS (HYMENOPTERA: VESPIDAE)* By David C. Post and Robert L. Jeanne Department of Entomology University of Wisconsin-Madison Madison, Wisconsin 53706 Although 13 exocrine glands have been located in wasps of the genus Polistes, and 12 in Mischocyttarus (Landolt and Akre, 1979), their morphology and functions have been little studied. Recently, however, the sternal gland on the sixth gastral (terminal) segment of females of these wasps has attracted attention because its secretion is repugnant to some species of ants. Female wasps rub the secretion onto the nest petiole, thus forming a chemical barrier against predatory ants (Jeanne, 1970; Hermann and Dirks, 1974; Turillazzi and Ugolini, 1978, 1979; Post, 1980). Close to the anterior margin of the sternite is a hyaline area covered with a tuft of long hairs (‘sternal brush’) (van der Vecht, 1968). In Polistes a cluster of gland cells underlies the cuticle on each side of the sternal brush (Landolt and Akre, 1979; Turillazzi, 1979). Ducts lead from the gland cells to the cuticular surface within the sternal brush. A smaller number of gland cells also occurs in a band along the anterior margin of the fifth gastral sternite (Hermann and Dirks, 1974; Turillazzi, 1979). We undertook the present study to determine the presence of these glands in Polistes fuscatus (F.), a temperate zone species, and in P. canadensis (L.), a tropical species, and to compare the size and morphology of the glands in these species with those in congeners previously investigated by Hermann and Dirks (1974) and Turillazzi (1979) Materials and Methods Adult female foundresses and workers of P. fuscatus (F.) were collected in Madison, Wisconsin, on 13 June, 2 and 21 July, and 9 September, 1978. Adult P. canadensis canadensis (L.) were collected *Manuscript received by the editor July 3, 1980. 49 50 Psyche [Vol. 87 at Taperinha, near Santarem, Para, Brazil (2° 32'S, 54° 20'W) on 13 November 1978. P. canadensis specimens were collected from both pre- and post-emergence nests. After fixing the wasps in Kahle’s solution, the sternites and attached tissue were removed and embedded in Spurr Low-Viscosity embedding media (Polysciences) following the methods of Spurr (1969). Sections 2/j thick were cut with a glass knife on a Porter-Blum-Ultra-Microtome MT-1 (Sorvall®) for examination with the light microscope. Staining was with Mallory’s Azure II-Methylene Blue (Richardson et al., 1960). For SEM preparations specimens were dehydrated in 100% ethanol and sonified. After air drying the tissues were coated with a thin layer of gold-palladium and examined with a JELCO JSM-U3 scanning electron microscope at 20 kV. Images were recorded on Polaroid film (Type 55, P/N). Adult females of each species were dissected in order to estimate the number of gland cells in the terminal sternite. The number of cells in each gland was estimated by determining the length and width of the glandular mass by means of a filar micrometer eyepiece, dividing each by 0.025mm (approximate diameter of an individual gland cell), multiplying the two results and then multiplying by the thickness of the gland, in numbers of gland cells (determined from histological sections) (1.25 for P. fuscatus and 2.5 for P. canadensis). Although this estimate does not give an exact count of the number of gland cells, it does allow a comparison of the relative number of gland cells in the two species. Results 6th Sternite. As in species studied previously, the anterior region of the terminal sternite of female P. fuscatus and P. canadensis bears a brush-like arrangement of dense hairs (Figs. 1 & 2). The brush is denser and more extensive in P. canadensis than in P. fuscatus. The cuticle underlying the brush is lightly sclerotized and translucent'(hyaline), but is not thinner than adjacent cuticle. The gland consists of two clusters of glandular cells (class 3 cells of Noirot and Quennedey, 1974), one on each side of the brush and hyaline area; there art no gland cells directly beneath the brush (Fig. 3). Each gland cell is connected by a duct to the sternal surface (Figs. 4 & 5). The majority of the ducts run mesad from the gland cells to the brush (Fig. 6) and £ oa M C/3 4 J . „ ) £ g <D ^ M CO C <L> <d C u f — 1 cd >» XI || <D <£ Ofl . . 0) o 6 £3 £ 3 s« — 1 cd II W> « II cd u O o 52 Psyche [Vol. 87 empty through the cuticle between the hairs (Fig. 5). A few ducts do not run to the brush, but empty through the cuticle lying directly over the gland cells (Fig. 4). In both species each mass of gland cells is enclosed by a thin basement membrane or lamella (Fig. 6). The gland is larger in P. canadensis than in P.fuscatus (Figs. 7 & 8). Each cluster of cells contains approximately 1676 cells (2 specimens) (56-105 cells per section; 4 specimens) in P. canadensis and 597 cells (3 specimens) (18-38 cells per section; 6 specimens) in P.fuscatus. The epithelium underlying the class 3 cells is thickened by the elongation of the epidermal cells, suggesting that these are secretory cells (class 1 cells of Noirot and Quennedey, 1974) (Figs. 4, 7, 8). This epithelium is thicker in P. canadensis (x= 34.0 //; 3 specimens) than in P.fuscatus (x= 15.5 //, 6 specimens). Epidermal cells not underlying the class 3 cells, including those in the hyaline area, are flattened and irregular in appearance (unmodified) in both P. canadensis (x= 6.4//; 3 specimens) and P. fuscatus (x = 5.8 //; 6 specimens). 5th Sternite. The anterior margin of the fifth gaslral sternite of both species bears a narrow band of class 3 gland cells, although a brush is lacking. Histological sections revealed fewer gland cells in P. canadensis (4-8 cells per section; 4 specimens) than in P. fuscatus (10-15 cells per section; 6 specimens) (Figs. 9 & 10). The gland cells are enclosed by a basement lamella. As on the sixth sternite, the epithelium lying under the class 3 cells is thickened, and is thicker in P. canadensis (x— 39.1 //;■ 3 specimens) than in P. fuscatus (x= 7.8 //; 3 specimens) (Figs. 9 & 10). There were no detectable individual differences in gland morpho¬ logy or development in either species. Discussion Our most important new finding is that the epidermal cells associated with the class 3 gland cells on both sternites are modified into what appear to be class 1 gland cells in both species. The reason Hermann and Dirks (1974) did not observe this in P. annularis (L.) may be attributed to their use of late pupae instead of adults. These cells may not become elongated until active. A second point on which P.fuscatus and P. canadensis apparently differ from what Hermann and Dirks (1974) report for P. annularis is that the class 3 cells of sternite 6 clearly form two clusters that lie to 1980] Post & Jeanne — Sternal Glands of Polistes 53 Figure 4. Longitudinal section (2 /r thick) through the glandular area of the sixth gastral sternite of P. canadensis. GC=glandular cells; E=epidermis; CD=glandular cell ducts. Figure 5. SEM photograph of the glandular cell duct openings (indicated by arrows) at the base of the sternal brush hairs of P.fuscalus. Anterior is to the upper right. Scale = 0.05 mm. Figure 6. Transverse section (2 /j thick) through the glandular area of the sixth gastral sternite of P. fuscatus. Midline is to the left. GC=glandular cells; AT=adipose tissue; CD=glandular cell ducts; BL=basement lamella. 54 Psyche [Vol. 87 Figure 7. Longitudinal section (2 u thick) through the glandular area of the sixth gastral sternite of P. fuscatus. Anterior is to the right. GC= glandular cells; E=epidermis; IM=intersegmental membrane; AT=adipose tissue. Figure 8. Longi¬ tudinal section (2 /U thick)'through the glandular area of the sixth gastral sternite of P. canadensis. Anterior is to the right. GC=glandular cells; E=epidermis; IM=interseg- mental membrane; AT=adipose tissue. the sides of the hyaline area and brush. Hermann and Dirks state that gland cells “extend beneath most of the integumental surface upon which the sternal brush is found” (p. 6), although their figures do not document this statement. Turillazzi (1979) showed clearly that in P. gallicus (L.) and P. foederatus (Kohl) the class 3 gland cells of sternite 6 form two lateral clusters. Hermann and Dirks (1974) found that the class 3 cells in P. annularis pupae were close packed and polygonal. Landolt and Akre (1979) argued that this is the undeveloped condition, and that the cells of active adult glands are globose. Our sections of active adult glands of P. fuscatus and P. canadensis clearly show these cells to be 1980] Post & Jeanne — Sternal Glands of Polistes 55 close packed and polygonal and bounded by a membrane. The discrepancy may be an artifact of the techniques used in each study. Hermann and Dirks (1974) sectioned fixed and embedded material, as we did, while Landolt and Akre (1979) dissected fixed specimens. It is possible that during dissection they may have ruptured the membrane enclosing the gland cells, allowing them to float free at the ends of their ducts and assume a spheroid form. On the other hand, it is possible that the difference is taxonomic. We have found that the class 3 cells on the fifth sternite of females of Polybia (Polistinae: Polybiini) are globose and apparently not bounded by a membrane, even in histological sections (Jeanne and Post, in preparation). It is not clear whether Landolt and Akre meant to generalize their statement to all genera they studied ( Vespula, Dolichovespula, Vespa, Polistes, and Mischocyttarus) or just to Vespula and Doli¬ chovespula. If the columnar epithelial cells associated with the ducted class 3 cells on the sixth sternite are indeed producing an exocrine secretion, it is not clear what its function could be. Even though this secretion would reach the cuticular surface to the side of the brush, it could well be applied to the nest petiole along with the product of the class 3 cells. Whether there it serves as a component of the ant repellent or has some other function is unknown. Alternatively, if it is volatile, it could evaporate from the cuticular surface, in which case its function is less likely to be involved with defense against ants. The fact that P. canadensis has approximately three times as many class 3 cells on sternite 6 as does P. fuscatus is consistent with the hypothesis that these cells produce the ant repellent that is applied to the nest petiole. Since ant predation pressure is higher in the tropics than temperate regions (Jeanne, 1979), one way P. canadensis, a tropical species, could counter this increased threat is by having more gland cells, producing greater amounts of ant repellent secretion. Turillazzi (1979) also found that P. gallicus, a species ranging into •northerp Europe, has fewer class 3 gland cells than does either P. omissus (Weyrauch) or P.foederatus, species of southern Europe and Africa (Kemper & Dohring, 1967). This correlation between gland size and geographic distribution need not, of course, rule out other hypotheses as to the function of the secretion. The role of the class 3 gland cells on sternite 5 is open to question. It is possible that the secretion has the same function as that of the 6th sternal gland, for, as Turillazzi (1979) points out, it would also be LULU f 0 '■ Figure 9. Longitudinal section (2 fji thick) through the glandular area of the fifth gastral sternite of P.fuscatus. Anterior is to the right. GC=glandular cells; E=epidermis; IM=intersegmental membrane; AT=adipose tissue; CD=glandular cell duct. Figure 10. Longitudinal section (2 fj thick) through the glandular area of the fifth gastral sternite of P. canadensis. Anterior is to the right. GC=glandular cells; E=epidermis; AT=adipose tissue. 1980] Post & Jeanne — Sternal Glands of Polistes 57 likely to be smeared onto the nest petiole during rubbing. On the other hand, at least three facts could be interpreted as arguments against an identical role: (1) P. fuscatus has more gland cells on the 5th sternite than does P. canadensis, just the reverse of the condition on sternite 6 (although the epidermal cells of this sternite are thicker in P. canadensis, suggesting perhaps that they have an independent function); (2) The tuft of long hairs present on sternite 6, where it presumably acts as an applicator brush, is absent from sternite 5; (3) the class 3 gland cells are distributed in a narrow transverse band on sternite 5, very unlike the two lateral clusters found on sternite 6. Although we detected no significant individual differences in gland size or morphology in either species, the ages and castes of our specimens were unknown. A careful EM study correlating degree of glandular activity with age and caste could provide useful insight into the function or functions of these glands. Acknowledgments B. Jane Harrington provided helpful comments on an earlier draft of this manuscript. Martin Garment provided assistance and advice on scanning electron microscopy. We thank Donas Erica and Violeta Hagmann for their generous hospitality shown us during our stay in Brazil. This research was supported in part by the College of Agricultural and Life Sciences, University of Wisconsin, Madison, and by National Science Foundation Grant BNS-77-04081. Literature Cited Hermann, H.R. and T.F. Dirks 1974. Sternal glands in Polistine wasps: morphology and associated behavior. J. Georgia Entomol. Soc. 9: 1-8. Jeanne, R.L. 1970. Chemical defense of brood by a social wasp. Science 168: 1465-1466. 1979. A latitudinal gradient in ant predation pressure. Ecology 60: 1211-1224. Kemper, H., and E. Dohring 1967. Die sozialen Faltenwespen Mitteleuropas. Paul Parey, Berlin. 180 pp. Landolt, P.J. and R.D. Akre. 1979. Occurrence and location of exocrine glands in some social Vespidae (Hymenoptera). Ann. Ent. Soc. Am. 72: 141-148. Noirot, C. and A. Quennedey 1974. Fine structure of insect epidermal glands. Ann. Rev. Entomol. 19: 61-80. Post, D C. 1980. Chemical defense in the temperate social wasp, Polistes fuscatus (Hymen¬ optera; Vespidae). M.Sc. Thesis, Univ. Wisconsin, Madison. 58 Psyche [Vol. 87 Richardson, K.C., L. Jarret and E.H. Finke 1960. Embedding in epoxy resins for ultra thin sectioning in electron microscopy. Stain Technol. 35: 313-323. Spurr, A.R. 1969. A low viscosity epoxy resin embedding medium for electron microscopy. J. Ultrastructure Res. 26: 31-43. Turillazzi, S. 1979. Tegumental glands in the abdomen of some European Polistes (Hymen- optera: Vespidae). Monitore Zool. Ital. (N.S.) 13: 67-70. Turillazzi, S. and A. Ugolini 1978. Nest defense in European Polistes (Hymenoptera: Vespidae). Monitore Zool. Ital. (N.S.) 12: 72. 1979. Rubbing behaviour in some European Polistes (Hymenoptera: Vespidae). Monitore Zool. Ital. (N.S.) 13: 129-142. Van Der Vecht, J. 1968. The terminal gastral sternite of female and worker social wasps. Proc. K. ned. Akad. Wet. (C) 71: 411-422. SANITARY BEHAVIOR BY THE SOCIAL SPIDER MALLOS GREGALIS (DICTYNIDAE): DISTRIBUTION OF EXCRETA AS RELATED TO WEB DENSITY AND ANIMAL MOVEMENTS.* By William J. Detjen Department of Biology Georgia College Milledgeville, Ga 31061 Introduction The organization of colony behavior by gregarious animals depends not only on the behavioral repertoire observed in individuals but also on physiological limitations evolution has imposed on the species. Such physiological restraints extend to the elimination of metabolic wastes by individuals which can affect the distribution of nutrients and parasites in the immediate environment (McBride, 1976). These by-products, in addition to prey remains, can have important consequences related to nest sanitation in social units of low vagility. In addition, metabolic wastes may perform a secondary communicative function in some species (Tietjen and Rovner, 1981). Mallos gregalis Simon is one such group-living species of spiders in which thousands of individuals of both sexes and various age groups occupy a semi-permanent web (Burgess, 1976; Diguet, 1908, 1915). To avoid fouling of such a long-term web site, one might expect sanitary behavior in such species. Unlike Agelena consociata, however, which exhibit nest-cleaning behavior by removing prey remains from the web (Krafft, 1969), M. gregalis do not remove carcasses, but incorporate prey remains into the nest structure (Jackson, 1978). Tietjen (1981) suggested that M. gregalis did not foul the web with fecal material, but eliminated wastes near the edge of the web. This produced a ring of excreta which surrounded the web site. These conclusions were, however, based upon observational, rather than experimental data. An alternative explanation can explain the observed ring of excreta: If M. gregalis utilize mainly the upper surface of the web they may deposit excreta uniformly over the web surface. If the excreta are incorporated into the web structure as are prey * Manuscript received by the editor September 8, 1980. 59 60 Psyche [Vol. 87 remains, then one would expect a similar ring of excreta to surround the web site in the laboratory. The present study quantitatively investigates the distribution of excreta as related to web structure and the distribution of spiders within experimental colonies in order to determine the possibility of systematic sanitary behavior in this species. The effects of group size and available building space on excreta distribution are also described. In addition, methodologies utilizing a computer-camera apparatus for data collection are presented. Methods I General Methods M. gregalis from a colony collected by G. W. Uetz near Mexico City, Mexico in 1979, was maintained in a climate-controlled room (T=25±5°C, RH=90±10%, natural photoperiod). Animals were daily given a fine spray of water on the surface of the web and were fed houseflies (Musca domestica ) at weekly intervals. One week prior to data collection, about 200 individuals were removed from the above colony; divided into approximatly equal¬ sized groups; transferred to four glass containers (13cm dia, 17cm height) and allowed to build webs. On the fifth day each group was fed 10 flies and two days later the colonies were split into samples for experimental analysis. Three group sizes (N=5, 10 or 20 adult females) were released into two different-sized petri dishes (large=96. lcc, small=52.2cc). Each group was allowed a two-week period (28 May-11 June 1980) to build a web. During this time they were not fed, but were watered daily by putting droplets of water near the edge of the petri dish. Photoperiod was natural for this summer time of year in North Carolina and temperature was 26.3±1.1°C. II Recording Methods. Detailed recording methodologies will be presented elsewhere (Tietjen, in prep.) or are available from the author. In brief, a solid- state television camera (Perificon type 511 image digitizer) was connected to a CDP-1802 microprocessor-based computer via a suitable interface. The computer acted as an “intellegent controller” of the camera and, through appropriate software (see below), could regulate the exposure time, number of frames per sec and the formating of data. Data were stored in computer memory during collection and were transferred to magnetic tape for future analyses. The camera provided a potential matrix array of 32 X 32 picture 1980 ] Tietjen — Sanitary Behavior of Malios gregalis 61 elements (=1024 pixels)-, however, a mask which simplified position analysis reduced the actual number of elements used in statistical analyses to 502 ± 10 pixels for the small and 571 ± 16 pixels for the large petri dish (Fig. 1). The camera was located ,65m from the recording surface providing a field of view for each pixel of 3.8mm 2 (about the size of a mature female M. gregalis). The density of silk at each of the 1024 positions within the container was recorded by programming the computer to begin at a short exposure time (13ms) and record in computer memory the positions of those pixels activated by light. The exposure time was then increased in ,03ms increments 1024 times. Each iteration resulted in darker areas in the field of view being recorded. This resulted in a grey-level representation of the image in 1024 levels at each of the positions. Because silk blocked out light, grey-level and silk density were inversely proportional. To compensate for possible uneven lighting effects and to scale the data to silk-density at each point, the above data were subtracted from base-level information obtained by taking a grey-level picture in Figure 1: Computer-controlled camera equipment designed to record the distribu¬ tions of animals and excreta as related to silk densities. Transmitted light (L) is provided by a light source and a refector (R) with a diffusion screen (D). Light passes through a transparent red plastic filter (F) and is reflected by an opaque white plastic mirror (M) which provides for further diffusion of the light. The light passes through a clear plastic base (B) and into a petri dish (P) which holds the experimental colony. An opaque mask blocks light outside the colony recording area and a hood (H) surrounding the recording area reduces the ambient light level seen by the camera (C). The camera is controlled by a computer which also receives the image data. This information is transmitted to a second computer for numerical analyses. 62 Psyche [Vol. 87 the absence of the spiders, excreta and web (e.g. just the base and petri dishes for each colony). Thus Si=B,—Gi where Si is the silk- density of the i l element in the array; B; is the base-level data and Gi is the grey-level data which included the colony. The more than 2.0 X 10 6 calculations required to construct the grey-level image took about 3 min of computer time. As it was not possible to remove the spiders without damaging the web and distribution of the silk, the spiders had to be killed prior to data collection since their movements would cause changes in the image. Following silk-density data collection, the positions of animals and excreta were recorded with the camera and the aid of a light pen. The silk-density data at these elements were affected by the presence of the animals or feces and were later adjusted to the average of the eight surrounding pixels for final analyses. In another experimental series, to record the position preferences of animals throughout the night, the computer took a picture in an intervalometer mode (1 frame per 3 sec), recording in computer memory those positions currently occupied by spiders (273724 frames total). Two colonies located in the small petri dishes were recorded for a five-day period (1600-0900; 5 animals per colony). The resulting data represented the amount of time each element of the array was occupied by an animal. This provided an estimate of the “attractiveness” of each position since favorable positions would be expected to have spiders occupying them for a greater amount of time than unattractive positions. Following collection of these data, I took a grey-level picture of the colony to record the approximate distribution of silk-density within the petri dish. All light received by the camera was transmitted through the colony. Transmitted light was provided by an incandecent bulb located in a reflector fitted with a diffusion screen. The light source was located 1.0m from the recording apparatus. Before the light was passed through the colony, it was reflected off a white plastic “mirror” to provide for further diffusion of the light. When collecting silk-density data I used a 200 W bulb. In order to record normal night activity, a 60W bulb was used in conjunction with a red filter and a hood to record the positions of living animals throughout the night (Fig. 1). The addition of the filter and hood reduced the light to the point where I could no longer recognize the positions of the animals with the unaided eye. The reduced light intensity did not affect camera operation because the camera’s peak sensitivity is in red light. 1980] Tietjen — Sanitary Behavior of Mallos gregalis 63 Following data collection, the information saved on tape was loaded back into the CDP-1802 computer and formated for analysis. Although the CDP-1802 computer is well suited as an intelligent controller, it is laborious to program statistical analyses in such a system. For this reason, the formated data were transmitted to another computer for numerical analyses (Ohio Scientific C1P). Statistical analyses were performed according to the methods of Conover (1971) and Sokal and Rohlf (1969). All means are accompa¬ nied by their standard deviations. Results The distribution of silk in all colonies was clumped with variance to mean ratios ranging from 79.4 to 126.0 (Chi-Square test p<.001; Table 1). Examination of the data indicated that nearly all of the silk was deposited near the periphery of the container with little or no silk deposited in the central area (Fig. 2, 3). The edge of the petri dishes contained numerous chambers and tunnels common to typical M. gregalis webs (Burgess, 1976). Most silk appeared to be dragline rather than cribellate silk. Table 1 Intermediate results for the number of animals, silk density and number of excreta for colonies of Mallos gregalis reared in containers of two sizes. The variance to mean ratios indicate considerable clumping of silk within all colonies (Chi-square test, pC.OOl). Silk density is expressed in arbitrary units related to the amount of light received by the camera. Number of Number of Mean Silk Variance to Mean Ratio Number of Excreta per Size Animals Pixels Density for Silk Colony small 5 511 257.1+148 85.2 16 5 487 226.5+140 86.5 10 5 510 272.7+198 88.6 13 20 503 312.1+198 126.0 43 20 500 363.3+170 79.4 34 large 5 582 255.9+151 89.2 12 5 588 273.6+154 86.6 30 10 555 265.2+148 82.4 27 10 576 284.1+161 91.8 31 20 554 322.6+194 116.9 30 64 Psyche [Vol. 87 The mean number of sampled elements in the small container was 502.2+9.7 pixels while the large petri dishes had 571.0+15.7 pixels. Within-group (e.g. large or small container) variation for number of elements did not show a significant difference (small: x 2= 0.75, ns; large x 2= l-72, ns) while considerable between-group variation was seen (Mann-Whitney test, T=0.0, p<.001). Repeated pictures of the same colony indicated that within-colony variation was low (0.95%). The small amount of within-group (large or small containers) and within-colony variation was due to the difficulties in representing a circular image with an array composed of square elements. The between-group variation was due to the different sizes of the containers. Most excreta located on the surface of the container were circular although a few irregular forms were seen. Margins were either smooth or undulate and color ranged from dark ebony to light tan; often with the central area being darker than the surrounding margin. The mean diameter was 1.1+0.4mm (N = 70; irregular forms were not measured) and there was no evidence of mold or bacterial growth (measured with a 10 X micrometer). In contrast to the above, it was very difficult to measure the dimensions of excreta deposited on silk as such material tended to flow along the silk line or adhere to adjacent threads. These excreta were whitish to tan in color and had a cracked appearance under 10X magnification. No mold or bacterial growth was seen. It was not possible because of the varied form and color of the excreta to quantify the amount of material at each deposition site by optical means. For this reason only the presence or absence of excreta was analyzed. To investigate the distribution of excreta as related to silk distribution, the silk density data were divided into ten levels (0-99, 100-199. . .900-1000 density units). No silk density data were greater than 1000 density units. This was necessary because of the relatively low number of fecal deposits in each container (Y= 24.6+11.0; Table 1; Fig.2). Analyzing each colony individually, a positive correlation was observed between the number of pixels within each of the ten silk-density ranges and the number of excreta (Spearman’s rho, p=+0.93, p<.01). In addition, examination of the data indicated similar distributions of excreta, animals and silk densities both between container sizes and among colony sizes. The data were therefore pooled for further analyses and a positive 1980] Tietjen — Sanitary Behavior of Malios gregalis 65 7 6 5 7 6 4 6 5 5 2 1 8 6 2 2 2 8 5 3 2 2 1 8 7 2 2 2 2 1 7 6 2 2 1 1 1 6 7 4 2 1 2 1 7 7 2 2 1 1 0 6 7 2 2 1 1 1 5 6 2 2 2 1 1 7 8 2 2 2 6 1 8 5 3 2 1 2 1 7 5 4 2 2 1 5 5 112 5 5 3 2 2 7 7 3 3 1 4 5 3 7 7 4 9 7 5 6 6 3 3 2 2 2 2 2 112 2 11 111 111 0 0 1 111 0 2 0 111 10 0 1 1 1 1 1 1 111 111 2 11 2 2 2 3 2 2 4 4 3 4 4 4 6 6 4 8 8 3 5 4 4 2 3 3 2 2 2 2 2 2 2 11 2 2 1 111 111 Oil 111 0 0 0 0 0 1 10 0 111 111 111 111 111 111 112 2 2 3 4 4 4 2 2 3 3 3 3 6 6 7 3 3 4 3 6 2 2 3 2 2 2 2 111 2 2 1 111 111 111 111 0 10 111 Oil 111 Oil 111 111 111 111 2 2 2 3 2 2 4 3 3 2 3 2 3 2 4 5 5 2 3 4 2 3 3 2 2 2 2 11 12 2 112 112 111 113 111 111 111 111 111 111 111 112 12 2 114 3 3 3 3 3 4 4 4 5 7 4 6 5 5 4 5 4 15 2 2 3 5 7 2 2 3 6 7 2 2 2 4 6 2 2 3 3 5 1 2 2 2 3 7 6 3 1 1 3 3 5 6 1 2 2 2 2 5 7 1 3 3 2 2 5 6 1 2 2 2 2 5 7 1 2 2 3 3 5 6 1 2 2 3 4 6 1 2 2 4 5 5 12 13 3 2 2 3 3 5 2 3 3 4 6 4 3 3 5 Figure 2: Representative silk-density image (A) and distribution data for animal and excreta positions (F). Silk-density data have been adjusted to a ten-level ordinal scale with 9 representing the highest observed silk densities. Note that the most dense silk is found mainly at the outer edge of the container. Figure 2B shows the distribution of fecal material (F) and the dead animals’ last positions (A). Data matrices such as these were used in the Model 1 and Model 2 analyses. 6 6 a 0011221000 M 44110000121113 842011233222011014 552200111111002233 954341234443321100029 33774201324432003521459 11221133443344220100239 545 6 0022112211001111469 3340012423487112200003359 85771000101354001100014469 21450111311111011200001256 54651000101111100000522399 32010011100000110010001276 53320000000010001000002479 322001000000000000000226 66010000000100000 0 01449 22000000000001011 0 00339 3311000000000000001257 6100000001011111101279 21110100000000000449 3110000100010001688 2101011111123499 110001002399 8 7 5 6 7 9 9 9 9 B 6654665555 77525566665555 977654463324656649 994477442655666655 959978742000011442765 96799871200000044777799 97877000000000003787677 97877110000000000567889 9767451000000000002257669 99877550000000000000244879 95567340000110000220514349 98566231000100013013595569 95567210000000022124150669 99567332011202101102222679 965655336610000022003455 97766205000100011332589 97764540025000110002577 9664542331000110000249 9945532000000000055459 99675512061001555489 9974431166261120339 9954320110125689 994444444467 9 9 9 9 9 9 Figure 3: Representative silk density data (A) and live animal frequency distribution data (B). The silk-density scale is linear and is presented as in Fig. 2A. The animal distribution data have been transformed by Log e to indicate that animals did exhibit some short-time presence in the central (low silk density) area. Data such as these were used in the Model 3 approximation. 66 Psyche [Vol. 87 correlation was observed between the amount of silk in each of the ten ranges and fecal deposition (Spearman’s rho, p=0.71, p<.025; Fig. 2,3). These data suggest that excreta were relatively evenly distributed throughout the container. Comparing the observed distribution of fecal material with the expected based on silk density, however, resulted in a significant deviation with too few excreta found at the extreme ranges (x z =20.7, p<.02; Fig. 4). The distribution of excreta as related to the silk-density distribution is referred to as my “Model 1 approximation”. In a similar manner, the distribution of the spiders’ last positions (dead animals) was analyzed. These data indicated a clumped distribution as related to silk density (x 2 = 106.0, p<.001) with the lower silk densities exhibiting too few spiders and the high-density silk locations, an excess number of spiders. When the expected distribution of excreta was adjusted to the observed distribution of the animals’ last positions, too few excreta were found at the high- density areas and an excess was found at low-density areas (x 2 =249.2, p<.001; Fig 4). These data suggest that animals eliminated wastes outside their most frequent occupation areas and are referred to as the “Model 2 approximation” in following sections. The data related to the animals’ last positions may not provide an accurate model of animal distribution over time as the distribution of these animals may have been affected by the killing process (e.g. animals may have abandoned their normal living areas during refrigeration). Such distributions (Fig. 2) were not typical of those observed in living colonies, as these colonies usually had a majority of the animals located in the periphery areas of the container. Figure 3 shows the distribution of living animals over time. Note that the scale is not linear but that the data have been transformed to Log e (Xi Without such a transformation, the entire central area and much of the periphery would show zero occupation. Nonetheless, animals were recorded as occupying matrix elements in the periphery of the container for the majority of the time and a positive correlation was observed between the time each position was occupied and that position’s silk density (Pearson’s r, r=+0.53, pC.OOl). Such a distribution of animals was expected based on casual observations of spiders in a variety of containers including petri dishes. These data suggest that the distribution of live animals was more contagious than might be expected from the above results based on the animals’ last position. When the expected distribution of excreta was adjusted 1980] Tietjen — Sanitary Behavior of Malios gregalis 67 to the model based on the distribution of living animals over time, a significant deviation was observed (x 2 =5960.3, p<.001), as approximately 86% of the fecal material would be expected to be found in the areas of highest silk density (Fig. 4). These data are referred to as the “Model 3 approximation” of expected excreta distribution. Although the meanjsilk density of the small vs. the large containers did not differ (small: (Y= 286.5± 170.2 units; large: (Y= 280.0+163.9 units; Man-Whitney test, T = 13, ns), a positive correlation was observed between the number of animals in each colony and the observed mean silk density (Spearman’s rho, p=+ 0.84, p<.001; Kruskal-Wallis test, T= 6.41, p<.05). Similarly, an animal-number effect was observed for the number of excreta (Spearman’s rho, p = + 0.82, p <.005). Therefore, an increased number of animals deposit both more silk and more fecal material (Table 1); however, these results do not affect the above analyses as the distribution of excreta, animals and silk did not differ among colonies of varying size or between container sizes. Discussion I. Evaluation of Methodology The apparatus cannot recognize structural features of the web (e.g. chambers and tunnels) but instead describes the web as a series of points having differing silk densities. As such structures tend to be enveloped in dense silk, however, the data do reflect the relative complexity of one area over another. Using methods similar to those used to record excreta positions, one could record the distribution of structural features within colonies. The testing of the colonies in a relatively confined space has both advantages and disadvantages. An obvious objection is related to the “unnaturalness” of the laboratory situation. In the field, however, as the animals roll leaves to support the web structure, one might expect the construction of similar confined spaces. A decided advantage of confinement is a reduction in web-shape variability among colonies thus allowing detailed statistical analyses with reasonable sample sizes. Such webs, although built in a confined space, are typical when compared to those built in larger containers. Hollar et al. (in review) indicated that M. gregalis prefer to build in the corners of various¬ sized containers (ranging from small glass vessels to room-sized environments). The utilization of the petri dishes by the spiders in 68 Psyche [Vol. 87 these experiments is as would be expected from the above data. Similarly, Witt (personal communication) has indicated that M. gregalis have a propensity to occupy the narrowest available space in various-sized vessels, usually resting at the outermost edge of circular containers and treating this area as the interior of the web. Comparable results were seen in the distributions of animals and the time spent at various positions within the petri dishes. The distributions of animals and varying silk densities in this experiment, when compared to the above data, suggest that M. gregalis treat the periphery of the petri dishes as web-interior and the central region as web-exterior. A third limitation was caused by the electrical response of the photodetectors to intermediate lighting conditions which may result in an erratic output. This problem was especially noticeable at the edge formed by the opaque mask surrounding the colonies. It was not possible to remove the mask as that would increase programming requirements beyond the present system’s capabilities. As a partial solution to this problem, the data points representing the outer edge of each colony were ignored in statistical analyses. This reduced the sample size only slightly and any possible bias introduced would have decreased the absolute level of the observed contagious distribution. The solution, therefore, would affect analyses only if the degree of clumping were considerably less pronounced than in these experiments. A final limitation was the relatively long period of time required to construct a grey-level image of the colony as this necessitated killing the spiders. Modifications to the electronics and computer program have since reduced computation time from just over 3 min to under 5 sec. The five-sec computation time should provide for a reliable grey- level image without requiring that the animals be killed. The apparatus does provide a means of nondisruptively assaying the shape of such webs and permits automated analysis of relatively large data sets. Such techniques should be applicable to a variety of animal distribution studies which use animals of a similar size to adult female M. gregalis and their relationship to environmental structure. In addition, the relatively low cost of such a system (under $600) should make this technology available to a variety of experimenters. Although in these experiments only transmitted light was used, reflected light (visible or IR) could be utilized if it were sufficiently diffused within the recording area. 1980] Tietjen — Sanitary Behavior of Malios gregalis 69 II Interpretation of Data Among the social insects, nest cleanliness occupies much of the workers’ efforts. In the social bees, for example, the hive is kept meticulously clean in a variety of ways: 1) brood cells are cleared of excreta and molted skins; 2) adults move to the outside of the hive to eliminate excreta; 3) injured larvae and pupae are eaten; 4) the dead are transported from the nest and 5) large debris are covered with propolis, thus isolating the foreign object from the nest environment. Such sanitary behavior by the workers retards or eliminates bacterial and fungal growth in the high-humidity environment of the hive (Morse, 1972; Wilson, 1971). Similar data suggest the existence of sanitary behavior in M. gregalis. The first-approximation model (based on the distribution of silk) indicated that excreta were nearly uniformly deposited over the surface of the web in all colonies (Fig. 4). These data suggest that M. gregalis exhibit little or no sanitary behavior as related to the deposition of excreta. The second and third-approximation models were based respectively on the animals’ last positions and the animals’ distribution over time. The latter two models indicated an inverse Figure 4: Relative silk densities vs. excreta for the threee excreta distribution models. Silk density increases from zero to nine. Unmarked bars indicate the observed distribution of feces for each relative silk density range. Cross-hatched bars represent the expected distribution based on the absolute quantity of silk within each density range (Model 1). Stippled bars are the expected distribution of excreta based on the animals’ last positions (Model 2). The dark bars represent the expected distribution of excreta based on continuous recording of the animals’ movements (Model 3). The asterisk-marked bars indicate a significant deviation from the observed excreta dis¬ tribution (Chi-square test, p<.01). 70 Psyche [Vol. 87 relationship between the areas occupied by spiders and the site of excreta deposition. These data indicated that spiders typically were associated with high-density silk sites (near the periphery of the containers) and, in contrast to the first model, that they deposit excreta outside their normal area of habitation. Thus, too many excreta were observed in areas of low silk density suggesting that sanitary behavior related to excreta deposition occurs in M. gregalis (Fig. 4). The limited amount of time spiders occupied the central area of low silk density (i.e. the outside of the web) suggest that, in part, they moved into this region in order to deposit excreta. Other possible reasons for visiting the central part of the containers include exploratory behavior and possible expansion of the web. Of the three models tested, the third is probably the most accurate as it depends on the actual distribution of living animals. As such, it indicates that animals deposit excreta at sites removed from their areas of occupation (i.e. in the area they treat as web-exterior). The malpighian tubules of spiders excrete guanine, adenine, hypoxanthine and uric acid into the cloaca with approximatly 34-76% of the excretory material being guanine (Anderson, 1966). The relative insolubility of these compounds makes it unlikely that the smooth-surfaced excreta deposited on the floor of the chambers could provide potential growth sites for bacterial and fungal colonies. The excreta found on silk, however, were cracked and pitted. Such cracks could provide potential growth sites for colonies in a high- humidity environment; however, under the present conditions no such growth was observed. In a related series of experiments, colonies of various sizes (10-80 individuals) were housed in glass containers (13 cm dia, 17 cm height; Witt, personal communication). Initially, the majority of spiders inhabited only the upper portions of the vessels. After 4-6 weeks, however, they began to leave the main web and built a separate secondary web in the lower part of the container. Six colonies were available for my examination, all of which had contained spiders for over two months. Fouling of the lower Web by excreta was evident on examination of the colonies. In addition, both fly and spider carcasses exhibited evidence of fungal and / or bacterial growth. Dead spiders and prey in the upper portion of the containers typically did not support such growth. Evidently, animals located in the upper section of the containers dropped fecal material onto the lower web. These data suggest that, under certain conditions, bacterial and / or fungal growth is supported by fouling of the nest. In 1980] Tietjen — Sanitary Behavior of Malios gregalis 71 nature, however, one would not expect a secondary colony to be formed beneath the primary colony since in the laboratory such associations are rarely seen. The data do indicate, however, that within-colony fouling could occur if M. gregalis did not exhibit sanitary behavior. Excreta produced by M. gregalis do not provide chemical messages, as spiders are neither attracted to nor are they repelled from conspecific excreta (Tietjen, unpubl. data). It is possible, however, that excreta could disrupt other modes of communication. A large amount of excreta on the web surface may make adjacent silk threads stick together, possibly affecting the vibration characteristics of the web. Such contamination may directly affect communication among nest mates as suggested by the work of Burgess (1979). Deposition of excreta outside the normal areas of habitation may reduce this potential problem. Localized excretion sites are, however, only one aspect of sanitary behavior. During the summer months in North Carolina, for example, it is surprising that prey carcasses in the web are not associated with bacterial or fungal growth, as similar organic matter outside the web provides an excellent growth medium for such colonies. Perhaps the venom and/or the digestive fluids of M. gregalis serve an additional function analogous to the agents found in honey which discourage bacterial growth (Morse, 1972). In addition to incorporating prey remains into the nest structure, exuviae and dead spiders are often seen in the web matrix. Rarely do the dead spiders exhibit evidence of bacterial or fungal growth and often do these spiders appear as if they have been fed upon (e.g they are dried and shrunken). Jackson (1979) reports two instances of cannibalism in M. gregalis and others in this laboratory have observed similar behavior (Hollar and Scarboro, personal communication; Tietjen, unpublished obervation). If only injured or dead individuals are cannibalized (this has not been determined, as cases of cannibalism are very rare) then this behavior may be similar in function to the cannibalistic nest cleaning behavior observed in bees and ants (Wilson, 1971). In a similar vein, I have recorded the distribution of dead spiders within and outside the webs of four colonies confined in glass containers (13 cm dia, 17 cm height) and found that 14 of the 29 dead spiders were found outside the web area on the bottom surface of the containers. Data presented in this paper (Model 3) would predict that the majority of dead individuals should be associated 72 Psyche [Vol. 87 with high-density silk sites (Fig. 3). If this were the case then the dead individuals may have been removed from the web by nestmates or, upon becoming ill, may have left the web on their own as has been described in ants, bees and termites (Wilson, 1971). I have observed one instance of oophagy by an adult female M. gregalis. Upon removing the uneaten eggs from the female, dissecting and examining them under a microscope (40X), I found the eggs to be desiccated, suggesting that the eggs were dead before the female began feeding. The consumption of nonliving egg masses would be expected to remove what would have been excellent growth media for bacteria, and similar behavior has been observed in bees and ants (Wilson, 1971). The rarity of the aforementioned events makes it unlikely that such behavior could be examined quantitatively. Possibly, many of the above behaviors are more prevalant at night when these animals are more active (Tietjen, 1981). Under such viewing conditions, it would be difficult to record cannibalism in M. gregalis. However, these data, in conjunction with the quantitative data presented in this paper, suggest that nest-cleaning and other related behaviors do occur in M. gregalis. Acknowledgements. I am grateful to Dr. P. N. Witt for many helpful discussions during the course of this research and the preparation of the manuscript. The research was supported by National Science Foundation grant BNS 75-09915 to P. N. Witt and W. J. Tietjen, and was conducted in the laboratories of the North Carolina Department of Mental Health. Literature Cited Anderson, J. W. 1966. The excreta of spiders. Comp. Biochem. Physiol. 17 : 973-982. Burgess, J. W. 1976. Social spiders. Scient. Am. 234: 100-106. 1979. Web-signal processing for tolerance and group predation in the social spider Malios gregalis Simon. Anim. Behav. 27: 157-164. Conover, W. J. 1971. Practical Nonparametric Statistics. New York: John Wiley and Sons, Inc. 492 pp. Diguet, L. 1908. Sur l’araignee mosquero. Comptes Rendu Acad. Sci. 148 : 735-736. 1915. Novelles observations sur le mosquero ou nid d’ araignees sociales. Bull. Soc. Nat. Acclim. Fr. 62: 240-249. 1980] Tietjen — Sanitary Behavior of Malios gregalis 73 Hollar, W. D., P. N. Witt, M. B. Scarboro and D. B. Peakall 1980. Aggregation: an adaptive stategy in Mallos gregalis Simon (Araneae, Dictynidae). (in review). Jackson, R. R. 1978. Comparative studies of Diclyna and Mallos (Araneae, Dictynidae) 1, Social organization and web characteristics. Rev. Arachnol. 1: 133-164. 1979. Comparative studies of Dictyna and Mallos (Araneae, Dictynidae) II: The relationship between courtship, mating, aggression and cannibalism in species with differing types of social organization. Rev. Arachnol. 2:103-132. Krafft, B. 1969. Various aspects of the biology of Agelena consociata Denis when bred in the laboratory. Am. Zoologist. 9: 201-210. McBride, G. 1976. The study of social organizations. Behaviour. 59: 96-115. Morse, R.A. 1972. Environmental control in the beehive. Sci. Am. 226: 92-98. SOKAL, R. R. AND F. J. ROHLF 1969. Biometry. San Francisco: W. H. Freeman. 776 pp. Tietjen, W.J. 1981. Social organization in the spider Mallos gregalis Simon : Individual activity patterns and web-related effects, (in press). Image digitization techniques for the CDP 1802 microprocessor, (in prep.). Tietjen, W.J. and J. S. Rovner. 1981. Chemical communication in lycosids and other spiders. In: P.N. Witt and J.S.Rovner (Ed.) Spider Communication: Mechanisms and Ecological Significance. Princeton: Princeton University Press, (in press). Wilson, E.O. 1971. The Insect Societies. Cambridge: Belknap. 548pp. A SYNOPSIS OF THE CHRYSIDID GENERA OF NEOTROPICAL AMERICA (CHRYSIDOIDEA, HYMENOPTERA)* By Lynn S. Kimsey and Richard M. Bohart Department of Entomology, University of California, Davis 95616 The chrysidid fauna of Central and South America, including Mexico, differs considerably from that of North America. There are only a few species whose range extends into both regions. The genera Cleptes, Mesitiopterus, Microsega, Muesebeckidium, Pseudolopy- ga, Minymischa, Xerochrum, Microchridium, Hedychreides, Chry- sura, and Chrysurissa are not reported from South or Central America. A number of genera are not found north of Costa Rica, including Duckeia, Nesogyne and Gaullea. Trichrysis and Neo- chrysis have undergone extensive species radiation in the neotropics. The few species in these two genera occurring in North America are their northernmost representatives. The faunas of Baja California, north central and northwestern Mexico seem to be essentially temperate in origin. The genera Parnopes, Spintharosoma and Ceratochrysis belong to this temper¬ ate fauna and are considered in this survey because they are found in Mexico. Several of the genera found only in the southwestern United States may be present in Baja California, Sonora and Chihuahua, Mexico, so specimens from this region should probably be run through the key to the North American genera (Bohart and Kimsey, 1980). The chrysidid fauna of the Caribbean islands, excluding Trinidad and Tobago, appears to be primarily temperate in origin, with only one endemic genus, Nesogyne. The principal work on neotropical Chrysididae has been done by Juan Brethes, August Brulle, Robert du Buysson, Peter Cameron, Alphonse Ducke, Felix Guerin-Meneville, Karl Krombein, Alexan¬ dra Mocsary and Maximilien Spinola. Lesser work has been done by R. Benoist, H. Bischoff, R. M. Bohart, E. T. Cresson, A. da Costa Lima, Andrea Dahlbom, Vicente Perez-D’Angello, Johann Fabri- cius, Claude Joseph (H. Janvier), L. S. Kimsey, Walter Linsenmaier and Flaminio Ruiz. * Manuscript received by the editor August 26, 1980. 75 76 Psyche [Vol. 87 The two largest chrysidid genera in the neotropics are Trichrysis and Neochrysis, whose dominance roughly corresponds to Cerato- chrysis and Chrysis in the nearctic fauna. Detailed examination of Trichrysis in both hemispheres has revealed four distinct groups. Old World Trichrysis can be divided into two subgenera, based on whether the discoidal cell is complete ( Trichrysis s.s.) or incomplete (Chrysidea ). The New World Trichrysis can also be divided into two groups based on the same characteristic. However, New World Trichrysis are different from the Old World forms since they have a distinct and almost articulated telomere on the male genital capsule (fig. 24). This discrete telomere has not been found in Old World Trichrysis (fig. 22). We therefore propose the establishment of two new subgenera in the genus Trichrysis. An asterisk after a species name indicates that we have not seen the type. Trichrysis Lichtenstein Trichrysis (Caenochrysis) Kimsey and Bohart, new subgenus (derivation: Kaeno = new, Gr.) Subgenerotype: Chrysis tridens Lepeletier Included species: amazonica Mocsary, azteca Mocsary, brasiliana Guerin, carinata Say*, divergens Cresson, gibbosa Mocsary, mathani Ducke*, mucronata Brulle*, nigropolita Bischoff, par- vula Fabricius, taschenbergi Mocsary, triangulifera Mocsary, and tridens Lepeletier*. Discussion: Members of the subgenus can be recognized by the sometimes thin but completely sclerotized outer veins of the discoidal cell in the forewing (fig. 18), and the presence of a telomere on the paramere (fig. 24). Trichrysis (Lorochrysis) Kimsey and Bohart, new subgenus (deriv¬ ation: Loron = strap, Gr.) Subgenerotype: Chrysis doriae Gribodo ' Included species: areolata Mocsary, armata Mocsary, boscii Buys- son, crotonis Buysson, doriae Gribodo, puberula Spinola, quadri- rimosa Mocsary, saussurei Mocsary. Discussion: This subgenus is distinguished by a faint or incompletely sclerotized discoidal cell in the forewing, with at least the anterior vein faint or lacking (fig. 17) and the presence of a telomere on the paramere. In general the species are smaller than those of Caeno¬ chrysis. 1980] Kimsey & Bohart — Chrysidid Genera 77 Trichrysis (Trichrysis) Lichtenstein Subgenerotype: Sphex cyanea Linnaeus Discussion: Trichrysis s.s. is an eastern hemisphere group, recog¬ nizable by the completely sclerotized discoidal cell and no telomere on the paramere (fig. 22). Trichrysis (Chrysidea) Bischoff Subgenerotype: Chrysis pumila Klug Discussion: Chrysidea is also an eastern hemisphere group which lacks a telomere and has the forewing discoidal cell incomplete, since at least the anterior vein of the discoidal cell is lacking or faintly indicated. Neochrysis Linsenmaier Neochrysis is the largest genus in the neotropics. This genus was divided into four subgenera by Bohart (1966). We have further elaborated the characteristics of each subgenus and separated the neotropical species accordingly. The list of species under each subgenus may not be complete. Each list is based on species where we have seen the type or seen reliably determined material (type not seen indicated by an asterisk). Neochrysis Linsenmaier, 1959. Generotype by original designa¬ tion, Chrysis punctatissima Spinola, 1840 (nec Villers, 1789)= Chry¬ sis carina Brulle, 1846. T-III pit row obsolescent, pits, when discernible, no larger than other punctures (fig. 11); 4 distal teeth on T-III; frons without a cross carina or rarely a few traces of it, no strong carina leading back from brow to partly enclose midocellus; pronotum without a complete lateral carina; propodeum without a strong median projection just behind metanotum. Partial list of included species: cameroni (Buysson), carina Brulle, deuteroleuca (Mocsary), inseriata (Mocsary), lecointei Ducke, mon- tezuma (Cameron), paraensis (Ducke). Pleurochrysis Bohart, 1963, new name for Pleurocera Guerin (nec Rafinesque, 1818). Subgenerotype by monotypy, Chrysis viridis Guerin, 1842 (nec Oliver, 1790) = Chrysis bruchi Brethes, 1902. T-III pit row usually well developed and forming a strong groove, pits larger than punctures, at least laterally (fig. 12); 4 distal teeth on T-III or rarely 6; frons with or without a cross carina (fig. 13), 78 Psyche [Vol. 87 sometimes a strong carina leading back to partly enclose midocellus; pronotum without a complete lateral carina; propodeum without a projection behind metanotum. Partial list of included species: acuta (Brethes), alfkeni (Ducke), ameginoi (Brethes), ancilla (Buysson), bruchi (Brethes), cavifrons (Brulle), charruana (Brethes), chilicola (Mocsary), fasciifera (Bis- choff), lynchi (Brethes), mendozana (Mocsary), missionera (Brethes), postica (Brulle), ypirangensis (Buysson). Exochrysis Bohart, 1963, Subgenerotype by original designation, Chrysis panamensis Cameron, 1888. T-III pit row or groove well developed; 4 distal teeth on T-III; frons with a cross carina which branches back to enclose or partly enclose midocellus; pronotum with at most a partial lateral carina (fig. 5); propodeum with a strong median projection just behind metanotum (fig. 5). Partial list of included species: imperforata (Gribodo), leucophris (Mocsary), leucostigma (Mocsary), panamensis (Camer¬ on), spinigera (Spinola). Ipsiura Linsenmaier, 1959. Subgenerotype by original designation, Chrysis marginalis Brulle. T-III pit row or groove well developed; 2-6 distal teeth on T-III; frons sometimes with a cross carina but always with a carina leading back from brow to partly enclose midocellus; pronotum with a sharp and practically complete lateral carina or flange (fig. 4); propodeum without a projection behind metanotum (fig. 4). Partial list of included species: albibasalis (Mocsary), bisulcata (Ducke), brevispinosa (Ducke), ellampoides (Ducke), friesiana (Ducke), genbergi (Dahlbom)*, klugi Dahlbom, leucobasis (Mocsary), leuco- cheila (Mocsary), leucochiloides (Ducke), longiventris (Ducke), marginalis (Brulle), myops (Buysson), neolateralis Bohart, obidensis (Ducke), pilifrons (Cameron). Argochrysis Kimsey and Bohart, new genus (derivation: Argos = white Gr.) Generotype: Chrysis mesillae Cockerell Included species: mesillae (Cockerell), trochilus (Buysson) and a number of undescribed species. Discussion: This genus is distinguished by FI as long or longer than F-II in both sexes; tongue short, less than half as long as flagellum from basal fold to apex; mesopleuron with shallow transverse groove 1980] Kimsey & Bohart — Chrysidid Genera 79 or no groove; propodeal teeth tapering and apically pointed (fig. 14); (fig. 7) leg joints, and apical rim of T-III often white or hyaline; paramere digitate and or lobate (fig. 19); cuspis broadly rounded, and digitus equal to or shorter than cuspis and apically rounded (fig. 19). Examination of the type species of Spintharosoma Zimmermann, Chrysis chrysonota Dahlbom, from the Ethiopian Region reveals that the American species previously placed in this genus are not congeneric.In S. chrysonota the tongue is long, the propodeal teeth clublike (fig. 15), paramere simple and rounded and cuspis slender and tapering (fig. 21), the male F-I is less than one third as long as F- II, and the mesopleuron divided into two parts by a deep transverse groove. American species also differ from Spintharina (generotype Chrysis vagans Radovskowsky). Spintharina has two large teeth on the mesopleuron, lobate propodeal teeth (fig. 16), and male genitalia with simple unlobate paramere and long slender digitus and cuspis (fig. 20). Gaullea Buysson The genus Gaullea is an obscure and poorly known genus. Gaullea was originally described from a single female, collected in Chaco, Santiago del Estero, Argentina. We have seen an additional 2 females and 3 males from Santiago del Estero, Argentina, plus the type. This genus is characterized by the very short RS stub, lack of a discoidal cell in the forewing and denticulate rim of T-III (figs. 6, 10). Linsenmaier (1959) placed Gaullea near Euchroeus. However, after close examination of the wing venation we have placed Gaullea near Argochrysis, because a crease in the wing indicates that the marginal cell would be closed if the RS stub were extended. The closed marginal cell is characteristic of Chrysis and its relatives. The expanded and bladelike metanotum and denticulate rim of T-III suggests that Gaullea is closely related to Argochrysis. The male genitalia of Gaullea is similar to that of Chrysis, with a simple though somewhat apically lobate paramere, broad foliaceous digitus and slender setose cuspis (fig. 23). Biology Host records for the neotropical Chrysididae are incomplete at best and nonexistant for Nesogyne, Cleptidea, Amisega, Pseudo- spinolia and Gaullea. The Amiseginae are typically phasmatid egg parasites. The remaining genera are wasp and bee parasites (table 1). 80 Psyche [Vol. 87 Figs. 1-7, Lateral view of hody. 1. Duckeia cyanea Costa Lima. 2. Adelphe mexicana Mocsary. 3. Cleptidea aurora (Smith). 4. Neochrysis (Ipsiura) marginalis (Brulle). 5. Neochrysis (Exochrysis) panamensis (Cameron). 6. Gaullea argentina Buysson. 7. Argochrysis mesillae (Cockerell). 1980] Kimsey & Bohart — Chrysidid Genera 81 Figs. 8-12, Apical margin of tergum III. 8. Elampus nitidus (Aaron). 9. Omalus butleri Bohart and Campos. 10. Gaullea argentina Buysson. 11 . Neochrysis (Neochry¬ sis) carina (Brulle). 12. Neochrysis (Pleurochrysis) bruchi (Brethes). Fig. 13, Front view of male face of Neochrysis (Pleurochrysis) bruchi (Brethes). Figs. 14-16, Anteroventral view of propodeal tooth. 14. Argochrysis mesillae (Cockerell). 15. Spintharosoma chrysonota (Dahlbom). 16. Spintharina vagans Radovskowsky. Figs. 17-18, Forewing venation. 17. Trichrysis (Lorochrysis)doriae Gribodo. 18. Trichrysis (Caenochrysis) tridens (Lepeletier). 1980] Kimsey & Bohart — Chrysidid Genera 83 Very little biological work has been done on the neotropical chrysidids. Host data has been reported for Omalus by Benoist (1942), Trichrysis, Chrysis and Neochrysis by Perez-D’Angello (1968), Coville and Coville (1980), Ducke (1904), Fritz (pers. comm), Janvier (1933) and Ruiz (1938), Adelphe and Mesitiopterus by Krombein (1957) and Duckeia by Costa Lima (1936). Table I. Host records, distribution and number of species of neotropical Chrysididae. Subfamily Cleptinae Cleptidea —host not recorded; southern Mexico to Brazil; 6 species. Subfamily Amiseginae Duckeia —Phasmatidae: Prisopus sp. (eggs); Brazil; 1 species. Amisega —Phasmatidae?: Costa Rica to Brazil; 4 species. Mesitiopterus —Phasmatidae: Diapheromera sp. (eggs); southern Mexico to Venezuela; 2 species. Adelphe —Phasmatidae: Anisomorpha; Mexico to Brazil; 4 species. Nesogyne —host not recorded; Dominican Republic; 1 species Subfamily Elampinae Omalus —Sphecidae: Pemphredoninae: Stigmus; Mexico, Brazil, Argentina and Chile; 5 species. Elampus —Sphecidae (not recorded in neotropics); Cuba, Venezuela, Brazil, Argentina; Chile; 3 species. Holopyga —Sphecidae (not recorded in neotropics); Dominican Republic, Mexico, Brazil, Peru, Argentina, Chile; 7 species. Hedychridium —Sphecidae and Apoidea (not recorded in neo¬ tropics); Mexico to Chile; 3 species. Hedychrum —Sphecidae: Philanthinae?(not recorded in neotropics); widespread; 6 species. Subfamily Chrysididinae Chrysis —Eumenidae: Hypodynerus and Stenodynerus; widespread; 12 species. Ceratochrysis —Eumenidae, Sphecidae; Mexico: Chihuahua and Baja California; 2 species. 84 Psyche [Vol. 87 Pseudospinolia —host not recorded in neotropics; Chile; 1 species. Argochrysis —Sphecidae: Ammophila (not recorded in neotropics); Mexico: Chihuahua and Baja California. 1 species. Gaullea —host not recorded; Argentina; 1 species. Trichrysis —Sphecidae: Trypoxylon, Eumenidae; widespread; 20 species. Neochrysis —Sphecidae: Podium, Trypoxylon, Sceliphron; wide¬ spread; 32 species. Subfamily Parnopinae Parnopes —Sphecidae: Bembicini (prob. only on Microbembex in Mexico), northern Mexico, Sonora; 1 species. Acknowledgments We are very grateful to Ignacio and Raquel Cid del Prado for their work on translating the generic key into Spanish. Key to the Genera of Neotropical Chrysididae For brevity in the key the following abbreviations have been used: T for tergum, S for sternum and RS for radial sector. 1. Abdominal venter convex . 2 Abdominal venter flat to concave . 7 2. T-I-II together dorsally subequal to or shorter than length of T-III-IV (fig. 3); pronotum with submedial transverse groove (fig. 3); upper frons with groove descending from midocellus (Cleptinae) . Cleptidea Mocsary T-I-II together dorsally much longer than length of T-III-IV (figs 1, 2); pronotum usually without transverse groove; upper frons without median groove (Amiseginae) . 3 3. Propodeum rounded posterolaterally (fig. 1), pronotal lobes usually not reaching tegulae (fig. 1) . 4 Propodeum toothed posterolaterally (fig. 2), pronotal lobes reaching tegulae . 6 4. Pronotum medially depressed or grooved; S-II produced, keeled anteriorly; gena flanged; propodeum strongly produced, posterior face almost flat (fig. 1)_ Duckeia Costa Lima Pronotum not medially depressed, S-II simple; gena not flanged; propodeum broadly rounded posteriorly. 5 1980] Kimsey & Bohart — Chrysidid Genera 85 5. Scutum with notauli . Amisega Cameron Scutum without notauli . Mesitiopterus Ashmead 6. Pronotum with transverse anterior groove, female with normal wings; propodeal tooth broad, subtriangular (fig. 2) . . Adelphe Moscary Pronotum without transverse carina, female brachypterous, propodeal tooth slender and digitate . . Nesogyne Krombein 7. RS stub sclerotized for less than half marginal cell length (if vein is extended by its traces and wing crease to wing margin); outer veins of discoidal cell faint or barely indicated (fig. 6); tarsal claws various. 8 RS stub sclerotized for more than half marginal cell length (if vein is extended by its traces and wing crease to wing margin); outer veins of discoidal cell usually sclerotized (figs. 4, 5, 7); claws simple . 14 8. Last visible tergum spiculate along apical margin; claws simple . 9 Last visible tergum not spiculate along apical margin; claws dentate (Elampinae) . 10 9. Tongue exserted and reaching near base of abdomen, last visible tergum subapically depressed on either side of midline; females with three normally visible terga, males with four (Parnopinae) . Parnopes Latreille Tongue short, not exserted; last visible tergum not subapically depressed; both sexes with three normally visible terga (Chrysidinae) . Gaullea Buysson 10. Hindtarsal claw long and slender, with a medial, nearly per¬ pendicular tooth; frons with close punctation along inner eye margins (punctures less than one puncture diameter apart; scutellum not anteriorly carinate . . Hedychridium Abeille de Perrin Hindtarsal claw without a single, medial, nearly perpendicular tooth; other characteristics various . 11 11. Medial vein essentially straight or weakly curved; hindtibia and usually midtibia with a definite pit on inner surface toward apex; female S-III usually with a nodular apicomedial projection ... Hedychrum Latreille Medial vein strongly arched; hindtibia and midtibia without a pit on inner surface; female S-III without an apicomedial projec¬ tion . 12 86 Psyche [Vol. 87 12. Medial cell with numerous dark microsetae; last tergum with punctate medially unnotched apical margin; face hollowed and crossridged; hindtarsal claws usually with two to five subsidiary teeth (rarely only one subsidiary) . ... Holopyga Dahlbom Medial cell essentially asetose; last tergum apicomedially im- punctate and usually notched or compressed and snoutlike (figs. 8, 9); face hollowed without crossridging; hindtarsal claws various. 13 13. T-III apicomedially notched (fig. 9), emarginate or simple not compressed and snoutlike; metanotum rounded, not conical or produced and bladelike; scutum impunctate or with punctures clustered along or between notauli, except chilensis (Mocsary) . Omalus Panzer T-III apicomedially compressed and snoutlike (fig. 8); metano¬ tum conical or produced and bladelike; scutum densely punctate . Elampus Spinola 14. Radial sector ending before wing margin so that marginal cell is broadly open (fig. 4) . 15 Radial sector and its faintly sclerotized remnant narrowly closing marginal cell or almost so (figs. 7, 17, 18) . 19 15. T-III apical margin smooth, slightly prolonged medially, especi¬ ally in male, anterolateral angles of T-I not unusually sharp . Pseudospinolia Linsenmaier T-III ending in four to six teeth; anterolateral angles of T-I unusually sharp . 16 16. Propodeum with strong median projection just behind metano¬ tum (fig. 5) . Neochrysis (Exochrysis) Bohart Propodeum without strong median projection just behind metanotum . 17 17. Pronotum with sharp and practically complete lateral carina or flange (fig. 4) T-III pit row or groove well developed (as in fig. 12). Neochrysis (Ipsiura) Linsenmaier Pronotum without a sharp or practically complete lateral carina or flange; T-III pit row various . 18 18. T-III pit row obsolescent, pits, when discernible, no larger than other punctures (fig. 11); frons without cross carina, rarely with traces remaining and no carinae extending back toward ocelli . Neochrysis s.s. Linsenmaier T-III pit row well developed and forming a strong groove, at least 1980] Kimsey & Bohart — Chrysidid Genera 87 some pits larger than punctures (fig. 12); frons usually with cross carina and carinae extending back toward ocelli .... . Neochrysis (Pleurochrysis) Bohart 19. Outer veins of discoidal cell faint (fig. 17) . . Trichrysis (Lorochrysis) Kimsey and Bohart Outer veins of discoidal cell sclerotized (fig. 18). 20 20. T-III not apicomedially notched, usually with three to six teeth . 21 T-III apicomedially deeply notched, lacking subsidiary teeth, except on either side of notch, central Mexico north ... 22 21. T-III ending in three or fewer teeth or angles . . Trichrysis (Caenochrysis) Kimsey and Bohart T-III ending in four or six teeth or angles . ....! . Chrysis Linnaeus 22. Tibiae with pale basal markings and T-III rim whitish; or meta- notum conically produced (fig. 7) .. . Argochrysis Kimsey and Bohart Tibiae without pale markings and T-III rim not whitish; metano- tum not produced . Ceratochrysis Cooper Clave para les generos neotropicales de la familia Chrysididae 1. Region ventral del abdomen convexa . 2 Region ventral del abdomen plana o concava . 7 2. T-I-II dorsalmente subiguales o mas cortos que el largo de T-III- IV (fig. 3); pronotum con hendidura submedia transversa (fig. 3); frente superior con una hendidura descendiendo del ocelo medio (Cleptinae) . Cleptidea Mocsary T-I-II dorsalmente tan largos que el largo de T-III-IV (figs 1, 2); pronotum sin o con hendidura transversal; frente superior sin hendidura media (Amiseginae). 3 3. Propodeum redondeado posteriolateralmente (fig. 1), lobulos pronotales usualmente sin alcanzar la tegula (fig. 1) .... 4 Propodeum dentado posteriolateralmente (Fig. 2), lobulos pronotales alcanzando la tegula. 6 88 Psyche [Vol. 87 4. Pronotum en su parte media hundido o con hendidura; S-II forma una projecion angular anteriormente; gena con pro¬ jecion o borde; proprodeum evidentemente pronunciado posteriormente, extremo posterior casi piano (fig. 1). . Duckeia Costa Lima Pronotum sin depresion media; S-II simple; gena sin projecion alar; propodeum distintamente redondeado posteriormente . 5 5. Scutum con notauli . Amisega Cameron Scutum sin notauli. Mesitiopterus Ashmead 6 . Pronotum con hendidura transversal; hembra con alas normales; diente propodeal ancho, subtriangular (fig. 2) . . Adelphe Mocsary Pronotum sin hendidura transversal; hembra con alas bra- chypterous; diente propodeal alargado y angosto. . Nesogyne Krombein 7. RS fragmento esclerotizado, menor que la mitad del largo de la celula marginal (si la vena es extendida por sus trazos y plieque del ala marginal); venas externas de la celula discoidal tenues o apenas visibles (fig. 6); unas tarsales variables . 8 RS escleratizado mas de la mitad del largo de la celula marginal (si la vena es extendida por sus trazas y plieque de ala marginal); venas externas de la celula discoidal usualmente escleratizado (figs 4, 5, 7); unas tarsales simples . 14 8 . Ultimo tergum visible, espiculado a lo largo del margin apical; unas tarsales simples . 9 Ultimo tergum visible, no espiculado a lo largo del margin apical; unas tarsales dentadas (Elampinae) . 10 9. Lengua extendida, alcanza cerca la base del abdomen; ultimo tergum visible, subapicalmente hundido en su parte media; hembras con tres normalmente visibles terga, machos con cuatro (Parnopinae) . Parnopes Latreille Lengua corta, no se extiende; ultimo tergo visible no subapical¬ mente hundido; ambos sexos con tres normalmente visibles terga (Chrysididinae). Gaullea Buysson 10. Unas de les tarsos posteriores largas y delgadas, con un diente medio perpendicular; frente con cerrada puntacion a lo largo del margin interno del ojo (puntacion menos que el diametro de una puntacion distantes); scutellum no anteriormente con saliente . Hedychridium Abeille de Perrin 1980] Kimsey & Bohart — Chrysidid Genera 89 Unas tarsales posteriores simples, diente medio perpendicular presente; otras caracteristicas varias. 11 11. Vena media esencialmente recta o debilmente curvada; tibia posterior y tibia media usualmente con un claro hoyo en su superficie interna, cerca de su apice; S-III de la hembra usualmente con una proyeccion nodular medioapical . . Hedychrum Latreille Vena media fuertemente arqueada; tibia posterior y media hoyo sobre su superficie interna; S-III de la hembra sin una proyeccion medioapical. 12 12. Celula media con numerosas microsetas obscuras; ultimo tergo con mediana puntacion, no alcanza el margen apical; cara concava y con estriaciones transversales; unas traseras usual¬ mente con 2 a 5 dientes subsidiarios (raremente uno) . . Holopyga Dahlbom Celula media esencialmente sin setas; ultimo tergo sin mediana puntacion apical, usualmente con muescas o comprimido similar a una proyeccion truncada (figs 8, 9); cara concava sin estriaciones transversales; unas traseras varias . 13 13. T-III de la hembra medio apical con muescas (fig. 9), emarginado o simple no comprimido o comprimido y sin proyeccion truncada; metanotumo redondeado, no conico o aplanado; scutum con puntacion cerrada a lo largo o entre notauli, excepto chilensis (Mocsary) . Omalus Panzer T-III de la hembra medio apical comprimido y con projection truncada (fig. 8); metanotum con proyeccion conica o aplana- da; scutum densamente punteado . Elampus Spinola 14. Sector radial termina antes del margen del ala, celula marginal es ampliamente abierta (fig. 4) . 15 Sector radial con celula marginal angosta y debilmente esclera- tizado o casi cerrada (figs. 7, 17, 18) . 19 15. T-III margen apical liso, ligeramente prolongado, en su parte media, especialmente en machos; angulos anterolateral de T-I no extraordinariamente agudos . . Pseudospinolia Linsenmaier T-III termina en cuatro o seis dientes; angulos anterolaterales de T-I extraordinariamente agudo . 16 16. Propodeum con fuerte proyeccion media justo atrasdel metano¬ tum (fig. 5) . Neochrysis (Exochrysis) Bohart 90 Psyche [Vol. 87 Propodeum sin fuerte proyeccion media, justo atras del metano- tum . 27 17. Pronotum con borde agudo y practicamente completa carina lateral (fig. 4); T-III con hilera de hoyos bien desarrollados formando una hendidura (como fig. 12) . . Neochrysis (Ipsiura) Linsenmaier Pronotum sin borde agudo o completa carina; T-III hilera de hoyos varios . jg 18. T-III hilera de hoyos casi ausentes, hoyos cuando son discern- ibles, no tan largos que otras puntaciones (fig. 11); frente sin carina cruzada, raramente con remanentes y sin extenciones de la carinae hacia los ocelos . . Neochrysis s. s. Linsenmaier T-III con hilera de hayos bien desarollado y formando un fuerte surco, algunos hoyos tan grandes que una puntacion (fig. 12); frente usualmente con carina cruzada y carinae extendiendase hacia los ocelos. Neochrysis (Pleurochrysis) Bohart 19. Venas externas de la celula discoidal debiles (fig. 17) . . Trichrysis (Lorochrysis) Kimsey and Bohart Venas externas de la celula discoidal esclerotizadas (fig. 18) .. ... 20 20. T-III medio apical sin muescas, usualmente con tres, cuarto o seis dientes. 21 T-III medio apical profundamente con muescas, dientes subsi- darios ausentes, excepto sobre ambos lados de la muesca; central y norte de Mexico. 22 21. T-III terminado en tres o algunos dientes o angulos . . Trichrysis (Caenochrysis) Kimsey and Bohart T-III terminado en cuatro o seis dientes o angulos . . Chrysis Linnaeus 1980] Kimsey & Bohart — Chrysidid Genera 91 References Benoist, R. 1942. Les hymenopteres qui habitent les tiges de sonce aux environs de Quito. Ann. Ent. Soc. France 111:75-90. Bohart, R. M. 1966. The genus Neochrysis in America north of Mexico. Bull. Brooklyn Ent. Soc. 63:139-144. Costa Lima, A da. 1936. Sur un nouveau chryside: Duckeia Jubilaire E. L. Bouvier, pp. 173-175. COVILLE, R. E. AND P. L. COVILLE. 1980. Nesting biology and behavior of Trypoxylon (Trypargilum) tenoctitlan in Costa Rica. Ann. Ent. Soc. Amer. 73:110-119. Janvier, H. 1933. Etude biologique de quelques Hymenopteres du Chili. Ann. Sci. Nat. Zool., Paris (10)16(14):209-356. Krombein, K. V. 1957. A generic review of the Amiseginae, a group of phasmatid egg parasites and notes on the Adelphinae. Trans. Amer. Ent. Soc. 82:147-215. Linsenmaier, W. 1959. Revision der familie Chrysididae. Mitt. Schweiz. Ent. Ges. 32:1-232. Perez-D’Angello, V. 1968. Insectos asociados a los nidos de Hypodynerus lachesis (Lepeletier). Rev. Chilena Ent. 6:131-134. Ruiz, F. 1938. Observaciones biologicas de algunos insectos chilenos. Rev. Univ. 23:148-153. 1939. El Odynerus labiatus Hal. y su biologia. Rev. Chilena Hist. Nat. 42:97-105. OBSERVATIONS ON THE WEB AND BEHAVIOR OF WENDILGARDA SPIDERS (ARANEAE: THERIDIOSOMATIDAE) By Jonathan Coddington 1 and Carlos E. Valerio 2 Introduction Theridiosomatidae are a small family of mostly tropical spiders that are related to the common orb-weaver family Araneidae. It is known that theridiosomatids spin modified orb-webs, but only the web of the holarctic Theridiosoma gemmosum (C. L. Koch) has been studied in any detail (McCook, 1889; Wiehle, 1931). Recently we independently discovered the unusual webs of some tropical theridio- somatid spiders that the senior author later identified as belonging to the genus Wendilgarda. The architecture and operation of these webs are unique among known spider webs. The sticky lines of the web are connected to the surface films of moving streams, and moreover are under considerable tension, more tension than can be accounted for by the action of water surface tension on an inert filament alone. The attachment of the sticky lines to the water surface is integral to the operation of the web. The sticky lines function by ensnaring insects that are themselves on the surface film of the water and are floating downstream. Materials and Methods Our observations refer to populations in Costa Rica (OTS Finca La Selva, Heredia; Punta Llorona, Puntarenas), Guatemala (Santo Tomas, Izabal), and Honduras (Nuevo Rosario, San Juancito). Conclusive identifications of these spiders are not possible until the genus is revised (Coddington, in prep.), but our observations refer to at least three species, all of the genus Wendilgarda. Voucher specimens are deposited in the Museum of Comparative Zoology, Harvard University. Behavior of the spiders was observed by shining a headlamp obliquely at the subject and using a simple 5X handlens. Museum of Comparative Zoology Laboratories, Harvard University, Cambridge, Mass., 02138, USA. 2 Escuela de Biologia, Universidad de Costa Rica, Costa Rica Manuscript received by the editor June 20, 1980. 93 94 Psyche [Vol. 87 The webs were observed after they had been dusted with cornstarch to heighten contrast. If there was a possibility that the cornstarch could alter the feature of the web being observed, the observations were verified on undusted webs. The accompanying photographs are all of webs that have been dusted with cornstarch, and measurements of thread lengths were taken from similar calibrated photographs of dusted webs. Habitat. The Wendilgarda species we observed occurred above streams flowing through relatively flat areas of wet tropical forest. The streams were of moderate size, usually 3-4 m across, and 0.3-0.6 m in depth. Flow rates at the surface of Quebrada el Sura at La Selva averaged 2.8m/sec (S.D. =0.02 m/sec) on the days we observed the webs. The webs themselves were found at the edge of the stream or in the lee of a protruding snag in the stream where the flow rate is considerably less, averaging 0.13 m/sec (S.D. = 0.03 m/sec) at La Selva. Web architecture. As far as we know, the webs of Wendilgarda species are qualitatively indistinguishable in the field, and so our comments apply equally to any of the populations we observed. Each Wendilgarda web (Fig. la-c) consisted of a variable number of interconnecting, more or less horizontal lines of non-sticky silk. The horizontal lines connected in a dendritic pattern; closed polygonal cells of the sort typical of most other spider webs were never observed. The free ends of the horizontal lines attached directly to substrates in the web site, such as leaves or branches of overhanging plants, or woody debris in the stream itself. The webs did not have “frame lines” such as are typical of the orb-webs of other theridioso- matid genera or araneid spiders. An entire functional web may contain only one such horizontal non-sticky line or as many as six; the average number was three (n = 14 webs). The height of the horizontal lines above the stream surface ranged from 10 to 39 mm. They varied in length from 23 to 160 mm, averaging 86 mm (n = 22 horizontal lines). Occasionally the center of the web, or where the usually three horizontal lines intersected, was supported from vegetation above by one or two “guy lines” (Fig. la), but many of the webs occurred in sites with no objects immediately above the web, and, hence, with no guy lines to the web center. Usually the spider hung ventral side up on accessory lines at the periphery of the web, or hung suspended from the junction of two or more horizontal lines (Figs, la, lb, 3a). 1980] Codding ton & Valerio — Wendilgarda Spiders 95 Figure la-c. Three examples of typical Wendilgarda webs. In Fig. lb, at left is visible a sticky line whose junction to the water film has popped. A comparison of the resting length with more extended lengths of sticky lines in the photograph is additional evidence of the tension in the sticky lines. Photographs taken at OTS field station Finca La Selva. The webs have been dusted with cornstarch to heighten contrast. The scale lines are 10 mm. 96 Psyche [Vol. 87 Extending downward from each of the horizontal lines was a series of vertical threads made of sticky silk. The sticky silk lines never connected two horizontal lines, but only the horizontal non-sticky lines and the water surface. We observed a range of 1 to 16 vertical sticky lines per horizontal line, averaging 6 per line (n = 30 horizontal lines). The spacing between the sticky lines along the horizontal line varied from 11 mm to 25 mm, averaging 23 mm (n = 16 horizontal lines), giving the whole web the appearance of several sparse combs perpendicular to the water surface. The ends of the sticky lines not attached to the horizontal lines terminated at the water surface, extending neither along the water surface nor below it to any solid object. Sticky line-water junctions. Several experiments and observations support our observations that the lower ends of the sticky lines terminate at the surface film of the moving stream. 1. Any probe, such as a stick or pencil, may be moved between, under, and completely around the point of attachment of the sticky line to the water surface without engaging or disturbing the sticky line. This shows that none of the sticky lines extends below the water surface, that there is no bottom horizontal line that connects the ends of the vertical sticky lines, and that the sticky lines do not extend upstream or downstream for any appreciable distance from their point of attachment with the stream. 2. The probe can be moved to within 2 or 3 mm of the thread- water junction without snagging it, althought if it approaches too closely on the water film, the attachment point of the silk will slide toward the probe as one would expect of two free objects floating and juxtaposed on a water film. Therefore, the movement of the attachment point is not restricted. 3. If a wettable but non-porous surface, such as a leaf, is first submerged in the stream, and then slowly brought up from under the surface to intersect the sticky line attachment point, and then completely out of the stream, the sticky line will come away with the water film on the leaf behaving in every way as if it was still attached to the stream surface. If wet leaf is then re-submerged in the stream, as soon as the water film on the leaf becomes continuous with the stream surface film, the attachment point will slide off the leaf and resume its former position directly beneath the horizontal line to which it is attached. These observations imply that even when the sticky line is attached to 1980] Coddington & Valerio — Wendilgarda Spiders 97 a water film on a leaf, and is completely free of the stream, it is only attached to the film, and not to the leaf itself. In this way one can observe the attachment point more closely; even under 20X magnifi¬ cation there are no discernible accessory lines leading away from the immediate locus of the thread. An increase in the tension on the sticky thread results in an increase in the distortion of the water film at the site of the thread junction. The water film can be pulled upward by the thread into the shape of a cone, strongly suggesting that there is some sort of interaction between the silk and the water film. If the sticky thread is now coated with cornstarch, there is a noticeable accumulation at the thread-water junction, covering essentially the area of the water film distorted by the tension in the sticky line. If a similar piece of non-sticky Wendilgarda silk is lowered into water and coated with cornstarch, no such accumulation is seen. Web tension. Apparently the vertical sticky lines are under more tension than can be explained by the action of water surface tension on a simple inert filament. We make this conclusion based on the following observations. 1. Except in web sites where the surficial flow rate exceeds about 0.2 m/sec, the sticky lines pass straight into the stream, approxi¬ mately normal to the water surface. As any fisherman has observed, inert lines with little drag on them always sag down¬ stream in a current. The angle of the sag depends upon the drag and the current. Although increased flow rates do move the point of attachment of a sticky line downstream with respect to the horizontal line, the path described by the sticky line is essentially straight with no observable sag. This suggests that it behaves like elastic filament under a tension whose magnitude far exceeds its weight per unit length. 2. If non-sticky segments of Wendilgarda silk are immersed in the water film of the same web site from which they were collected, they behave like inert fibers: they point downstream, there is an observable sag in the aerial portion of the line, and it requires no noticeable force to pull them out of the water. 3. If the horizontal line of a Wendilgarda web is held at the point of attachment of a sticky line, and slowly raised until the water- thread junction fails, the sticky thread elongates 50% to 100% of its original length. Also, if the water-silk junction is broken artifi¬ cially, and the sticky line allowed to hang under the stress of its own weight, it is typically only half the length it assumed when in 98 Psyche [Vol. 87 Figure 2. A Wendilgarda in fairly fast current, showing the deflection of the horizontal line due to the tension in the vertical sticky threads. Photograph taken at OTS Finca La Selva. The web has been dusted with cornstarch to heighten contrast. the web (e.g., sticky line on left horizontal thread, Fig. lb). 4. The horizontal line to which a series of sticky lines is attached is usually distorted by the tension in the sticky lines. When viewed in elevation, the horizontal lines look like a series of straight line segments approximating a curve, with the sticky lines connecting at the vertices of the angles between the segments (Fig. 2). 5. If the junctions between the sticky lines and the water surface are broken, the horizontal line springs upward to become essentially a straight line connecting its endpoints. In a few instances some sag in the horizontal line remained, but it was always less than before the sticky line-water junctions were severed (Figs. 3a, 3b). 6. One can clearly see the elastic response of the web to variation in the height and flow rate of the stream (Fig. 2). The stream height fluctuated naturally about +5 mm, and in highly tensed webs even this increase in tension was occasionally sufficient to “pop” some of the sticky lines free of the water surface. 7. Webs also popped if subjected to moderate-sized waves. In this case the leading edge of the wave apparently washed over the lower 1980] Coddington & Valerio — Wendilgarda Spiders 99 Figure 3a. A Wendilgarda web under tension opposed by the sticky line-water junctions. 3b. The same web after the sticky line-water junctions were severed, showing the decreased deflection of the horizontal line. Both webs have been dusted with cornstarch to heighten contrast. The scale lines are 10 mm. 100 Psyche [Vol. 87 segments of the sticky lines but the water remained fastened to the highest point on the line it reached. Hence when the stream returned to its normal height, the sticky lines were under excessive stress and the water junction failed. Web Function and Behavior of the Spider Web function. We were never fortunate enough to witness the complete natural sequence of prey capture by Wendilgarda spiders. However, Figure 4 is a photograph of an insect exuvium which floated downstream and contacted one of the sticky lines of a Wendilgarda web. The exuvium was dry, and merely resting on the surface of the water. It initially touched only one of the sticky lines. Apparently the lines adhere preferentially to cuticle in comparison to water, because it seemed that on contact the line stuck to the exuvium while the sticky line-water junction broke. Fastened to the web by the single sticky line, the exuvium oscillated back and forth in the current until, in the space of a few seconds, it contacted several other sticky lines. At this point we dusted the web to photograph the event. Attack behavior. Portions of the attack behavior of Wendilgarda spiders can be elicited by vibrating a sticky line or the water next to it with a tuning fork. The response of the spider is fairly sterotyped and follows one of two patterns. 1. The spider may move rapidly along the horizontal line to a point above the tuning fork and reel in the sticky line until the sticky line-water junction breaks. This action involves consider¬ able deflection of the horizontal line. The spider then hauls up the sticky line and searches the space around the end for a few seconds, rolling up the line and turning it over with its first two pairs of legs. After a variable length of time, the spiders usually reversed direction and returned to the center or periphery of the web. In the case where the tuning fork is actually stuck to the sticky line, the spider by pulling on the sticky line would pull itself and the horizontal line down the entire distance to the water surface. It then would palpate the tuning fork with its first two pairs of legs, and apparently attempt to bite the tuning fork. 2. In about half the number of presentations of the tuning fork, however, the spider did not simply move along the line toward the stimulus. The initial response of the spider was to cut the horizontal line at some point fairly close to its connection with the 1980] Coddington & Valerio — Wendilgarda Spiders 101 Figure 4. An insect exuvium caught in a Wendilgarda web. The web has been dusted with cornstarch to heighten contrast. Scale 5 mm. other horizontal lines composing the web. It would then attach a new silk line to the web behind it, and progress towards the stimulus by pulling itself along the old horizontal line, reeling up the old line as it went. The disposition of old and new silk is only possible if the web has been lightly dusted with cornstarch before the spider starts to spin the new horizontal line. With this treatment, the old line is dusted and therefore visible while the new line is very difficult to see. It is possible that the presence of cornstarch on the web affects the spider’s behavior, but when the same attack sequence was seen on unstarched webs the movements of the spider’s legs appeared comparable. We have no observa¬ tions to suggest that the actions of spiders on dusted and undusted webs differ for this particular behavioral sequence. This pattern of approach on the horizontal line is significant because the spider did not reel in the sticky lines of the web as it progressed, but only the horizontal segments between them. 102 Psyche [Vol. 87 Consequently, as the spider reeled up the horizontal line segment between sticky lines, the two sticky lines gradually approached each other and eventually coalesced into one doubled sticky line, still attached to the water surface. The spider would thus “snowplow” toward the stimulus/carrying an increasing number of coalesced sticky lines forward with it. Eventually, when the spider reached the sticky thread transmitting the vibration, the coalesced mass of sticky threads, still attached to the water surface, would simultaneously contact the “prey”. One can infer from this type of approach behavior that the contact of the prey with one or two sticky lines alerts the spider to the presence of prey in the web and initially restrains the prey. However, the retention capabilities of the web are tremendously increased by the contact between the prey and the composite sticky “rope” accumulated by the spider as it approaches the site. Because the number of intervening lines can be substantial, the probability of the prey escaping is reduced, and the spider may gain time before it has to commit itself to subduing the entangled animal. We tried on several occasions to introduce prey into webs, but because of the complex current patterns in the sites in which the spiders built their webs, we were successful in only one instance. Here the spider was initially at the center of the web. It first oriented toward the horizontal line concerned and twitched the line several times with a rapid flexion of its first two pairs of legs. It then “snowplowed” toward the ensnared ant, reached the sticky line connected to the ant, and pulled itself and the horizontal line to the ant by reeling in the sticky “rope.” It then palpated the ant with the first pair of legs, dropped its hold on the sticky “rope,” reeled in the next horizontal line segment, and finally cut free the sticky “rope” to which the ant was attached. Web building. We have observations of several sequences of web construction, but need more information before the significance of the spider’s movements in the larger context of the behavior of other theridiosomatid genera or araneoid families can be reliably inter¬ preted. Our preliminary comparative studies suggest that the web¬ building behavior of Wendilgarda species can be homologized to that of Theridiosoma species, and that the non-sticky and sticky lines of the Wendilgarda web are homologous to the radii and viscid spirals of the theridiosomatid orb-web (Coddington, in prep.). Wendilgarda spiders may rebuild their webs as often as three times 1980] Coddington & Valerio — Wendilgarda Spiders 103 in twenty minutes. ft takes them an average of four minutes to build a web, and as little as one minute to construct the sticky lines for any one horizontal line. This rate of web replacement is unusually high among spiders, but is apparently necessary in the constantly changing environment in which Wendilgarda spiders build. As described above, the normal vagaries of stream current and height are often sufficient to pop sticky line attachments and consequently to render webs ineffectual. Of more interest, perhaps, are the overall large fluctuations to which many of these tropical streams are subject. Quebrada el Sura at La Selva, for example, routinely fluctuates a meter or more in height in response to the frequent rains, and, during more intense storms has raised 4-5 meters above its normal height, with a concomitant increase in flow rate (Thomas Ray, Cathy Andrews, pers. comm.). There is an obvious question as to where Wendilgarda spiders go during such high water periods. It is possible that they spin retreats on shore at the normal level of shoreline and simply wait out the flood under water, but, given the violence of the floods, it seems more likely that they would have to move to dry ground in order to survive. During major storms the distance involved could easily amount to ten meters. However, despite extensive searches we never found Wendilgarda spiders with webs on dry land. What taxes in the behavior of the spider permit such movement, or the relocation of the stream after a storm, are unknown. Discussion There is reason to suspect that all species of Wendilgarda spin such webs. Eugene Simon saw webs of Wendilgarda theridionina Simon in Venezuela. In 1895 he wrote:"... the web of Vendilgarda [sic], strung beneath the vault of humid rocks, which overhang torrents and pools, is a small, very elementary network, composed of a few threads radiating with little regularity, offering only the vaguest lineaments of a orb web.” (p. 916). Petrunkevitch (1930), describing the web of the same species in Puerto Rico wrote: “Spiders of both sexes live in dense woods, spinning their threads between rocks over brooks. These threads are so fine that it is impossible to see them, and the spider has the appearance of being suspended in the air without any support” (p. 301). It also is possible that Petrunkevitch was observing the web of W. mexicana Keyserling, since the species are difficult to 104 Psyche [Vol. 87 distinguish. Last, Fritz Vollrath collected what is probably W. galapagensis Archer from the Cocos Islands off the coast of Costa Rica, and noted on his collecting label, “second growth, single thread.” Currently, there are five other neotropical species placed in Wendilgarda. Of these, two are apparently known only from the type specimens, and the webs of none of these species are described. Although it is likely that a few of these names may have to be placed in synonymy when the genus is revised, we predict that all species of Wendilgarda will be found to spin these peculiar webs. Wendilgarda species have evolved a web that exploits a hitherto unknown property of silk fibroins. Obviously, the chemical nature of the silk, or silks, composing the sticky lines of Wendilgarda webs and their glandular source, as well as the molecular details of the silk- water junction are extremely important in the function of the web and require further study. Such facts as the amount of tension the web is normally under, or the amount it will maximally sustain, are being investigated. In addition, the relationship of the Wendilgarda web to the modified orb-webs constructed by other members of the family, and the behavior patterns used to construct it, may allow inferences about the evolution of the web architecture that so precariously straddles the terrestrial and aquatic environments. Summary We describe the web of the spider genus Wendilgarda. The webs of the three species thus far are indistinguishable in the field. They consist of a dendritic pattern of non-sticky horizontal lines spun above the surfaces of moving streams. Extending from the horizontal non-sticky lines are vertically oriented sticky lines that terminate at the surface of the stream. The ends of the vertical sticky lines are attached only to the surface film of the stream. The entire web is under considerable tension, and the tension is opposed by the sticky line-water function. We describe how the web functions, how it it used in the attack behavior of the spider, and suggest that the architecture of the Wendilgarda web can be related to the modified orb-webs characteristic of other theridiosomatid spiders. We would like to acknowledge the support of the Richmond Fund of Harvard University and an Organization of Tropical Studies RIAS grant to the senior author, which supported part of this research. We would also like to thank Dr. Herbert W. Levi, Dr. Robert M. Woollacott, Ms. Cecilia Lenk, and Mr. Mark Stowe for their comments on earlier drafts of the manusript. McCook, H. D. 1889. American Spiders and their Spinningwork, vol. 1. Philadelphia (pub¬ lished by the author). Petrunkevitch, A. 1930. The Spiders of Puerto Rico, part II. Trans. Conn. Acad. Arts & Sci. 30: 159-355. 1885. Histoire naturelle des Araignees, vol. 1, 2nd ed. Edouard Duruy, Paris. STUDIES ON NORTH AMERICAN CARBONIFEROUS INSECTS. 6. UPPER CARBONIFEROUS INSECTS FROM PENNSYLVANIA* By Frank M. Carpenter Museum of Comparative Zoology Harvard University, Cambridge, Mass. 02138 This study is based on fossil insects from the Anthracite Coal Fields of Pennsylvania. In 1977 Mr. William F. Klose II, of Noxen, Pennsylvania, sent me for identification a series of fossil insects that he had collected in beds belonging to the Llewellyn Group of the Allegheny Series. Subsequently he arranged for a loan of specimens in the Reading Public Museum and Art Gallery, all of which had been collected many years ago by Claude Weston Unger in beds apparently also belonging to the Allegheny Series. The age of the Allegheny is about equivalent to that of the Late Westphalian of Europe, possibly slightly older than the Carbondale Formation of Illinois, in which the Mazon Creek nodules occur, and considerably older than the insects-bearing beds at Commentry, France. Al¬ though remains of insects are found only very infrequently in the Anthracite Coal Fields and are usually fragmentary, the specimens are of much significance because of their age. The insects were apparently inhabitants of swampy regions. Remains of plants are well represented in both the Klose and Unger collections and are often preserved in close association with the insects. Mr. Klose has identified the plant genera Lepidodendron, Neropteris, Pecopteris, and Sphenophyllum from specimens occur¬ ring with insects on pieces of the shale. These plants were typical of the coal swamps of the Upper Carboniferous. Cockroaches were by far the predominate insects. Of the fifty specimens of insects in the collections at hand, forty-five, or 90%, belong to the Blattaria, a percentage that is typical for such coal beds. Four specimens represent the orders Protodonata, Caloneurodea, and Protorthop- tera, which will be discussed below. In addition, there is a specimen of a small insect [No. 11025 (K6345)] that appears to be related to *Manuscript received by the editor September 28, 1980. 107 108 Psyche [Vol. 87 the enigmatic Dictyocicada antiqua, from the Commentry shales; an account of this specimen will be included in another article dealing with Dictyocicada and related genera. Order Protodonata Very few specimens of this order have been found in the Upper Carboniferous deposits of North America. Up to the present, only five species have been described and all are known by single specimens. These are as follows: (1) Paralogus aeschnoides Scudder, 1893, Family Paralogidae, from East Providence, Rhode Island (Allegheny Series, comparable to the Upper Westphalian of Europe). (2) Palaeotherates pennsyl- vanicus Handlirsch, 1906, incertae familiae, from coal beds near Pittsburgh, Pennsylvania (Upper Pottsville, comparable to the Middle Westphalian of Europe). (3) Paralogopsis longipes Hand¬ lirsch, 1911, incertae familiae, from near Mazon Creek, Illinois (Carbondale Formation, comparable to Upper Westphalian of Europe). (4) Typus durhami Carpenter, 1960, Family Meganeuri- dae, from coal beds in Durham, Georgia (Lower Pottsville, com¬ parable to Lower Westphalian of Europe). (5) Oligotypus makow- skii Carpenter & Richardson, 1971, Family Paralogidae, from Pit 11, near Braidwood, Illinois (Carbondale Formation, comparable to the Upper Westphalian of Europe). We are now able to add a sixth specimen, collected in Schuykil Co., Pennsylvania, and contained in the Klose collection. Although a fragment, consisting of the basal part of a fore wing, the fossil is worthy of a formal description and a specific name. I have assigned the species to the genus Palaeotherates, the family position of which has been very problematical. Since the new species does not provide sufficient additional information to enable a family diagnosis, I still consider the genus incertae familiae. Palaeotherates Handlirsch, 1906 The type-species, pennsylvanicus, is known from a distal frag¬ ment of a wing with typical protodonate features. Since the new species, described below, is based on a basal fragment of a wing, there is no way of knowing how closely these two species may be related. I have placed the new species here in order to avoid the naming of another genus at this time. 1980] Carpenter — Carboniferous Insects 109 Palaeotherates analis, n.sp. Figure 1 Fore wing: length of preserved part of wing, 80 mm; its maximum width, 38 mm. The species differs from pennsylvanicus by its larger size and by the structure of the anal area. It is about twice the size of pennsylvanicus, and the first anal vein (1 A), at least the basal half of it, has no major branch. Type: No. 11028, (K6757) William Penn Memorial Museum, Harrisburg; collected by W.F. Klose II in a strip mine 400 meters east of bench mark 1271 on the St. Clair-Mahanoy City Road, Blythe township, Schuykil County, Pennsylvania; Allegheny Series; underclay Buck Mt. #5 coal. The specimen consists of the basal two- fifths of a fore wing; parts of the wing, especially the anal area, are clearly preserved, but some veins, as RS and CUP are very faint and uncertain. However, the convexities and concavities of the veins are clear and the homologies of the veins are obvious. The most distinctive feature of the wing is the absence, in the preserved part, of a major branch of 1A. In all other Protodonata known to me, 1A gives rise (at about the level of the peak of the curve in CUP) to a prominent branch, which in turn forms a series of simple branches leading to the hind margin of the wing. This insect was obviously larger than pennsylvanicus, the wing of which has been estimated to be 55 mm long (Carpenter, 1960). Compari- Figure 1. Palaeotherates analis, n.sp. Drawing of preserved part of wing, based on holotype, No. 11028, William Penn Memorial Museum. Length of fragment, 50 mm. Rl, radius; RS, radial sector; MA, anterior media; CUP, posterior cubitus; 1A, anal vein. 110 Psyche [Vol. 87 son with meganeurids suggests that the complete wing of analis was probably about 200 mm long, indicating a wing expanse of about 420 mm. I have identified the type specimen as a fore wing on the basis of the slope of the hind margin, the hind wing of protodonates having a broad anal area basally. However, the basal part of the wing of analis! widens more abruptly than that of the fore wing of other protodonates so far known, although the base itself is narrow. As mentioned above, I have placed analis in the genus Palaeo- therates in preference to naming a new genus and for the present I consider the shape, size and nature of the anal vein to be specific characteristics. The species is noteworthy as the sixth specimen of Protodonata to be found in the Upper Carboniferous of North America, and as the largest species of that series of fossils. Order Caloneurodea This taxon, chiefly based on the genus Caloneura from the Upper Carboniferous of Commentry, was originally named by Handlirsch (1929) as a suborder of the order Protorthoptera. Martynov (1938), after studying a series of related genera from the Permian of the Soviet Union, elevated the group to an order. Since then, the Commentry species have been revised (Carpenter, 1961) and many other genera and families have been named to receive species from the Permian of the Soviet Union and the Permian and Upper Carboniferous of the United States (Tillyard, 1937; Carpenter, 1943, 1970). Some of the additional species have led to a broadening of the concepts of the order and its relationships. These general topics will be considered in another article dealing with Caloneurodea from the Permian of Oklahoma, but I include here a brief statement of the characteristics of the order, as a preface to the description of a new species contained in the Klose collection and apparently belonging to the order. Although some of the body structures are known, the order Caloneurodea is based mainly on wings, which show three major characteristics: (1) the homonomous nature of the fore and hind wings, the hind pair lacking an enlarged anal area; (2) the origin of CUA from M near the wing base and its proximity to CUP for most of its length; (3) the numerous cross veins, which are either straight or somewhat reticulate and are very strongly developed and thick, 1980] Carpenter — Carboniferous Insects 111 forming a series of ridges over the wing surface. Details of the body structures are known only in one species, Paleuthygramma tenui- corne Martynov, 1938, from the Permian of the Soviet Union. The numerous specimens of this species enabled Martynov (1938) and Sharov (1966) to reconstruct its more general features. The anten¬ nae were elongate and setaceous; the legs cursorial, very long and slender; and prothorax short and broad; the females possessed short cerci and a short ovipositor; the male abdomen terminated in a pair of foreceps, apparently modified cerci and similar to those of the Dermaptera. Whether or not the body structure of Paleuthygramma was typical of all Caloneurodea, we have no means of knowing at present, but the evidence, such as it is, suggests that the Caloneuro¬ dea were specialized members of the orthopteroid complex, con¬ sidered in its broadest sense. 1 The order is known from the Upper Carboniferous and Permian of North America, Europe, and Asia. Only two species of Caloneurodea have been recorded from the Upper Carboniferous of North America. One of these, Caloneurella carbonaria Carpenter, 1934, is from the Freeport Stage, Allegheny Series, South Good Spring Colliery, near Tremont, Pennsylvania; the other, Pseudobiella fasciata Carpenter, 1970, is from the Madera Formation, Desmoinesian Series (comparable to Upper Westphalian of Europe), near Albuquerque, New Mexico. The description of the new species in the Klose collection from Pennsyl¬ vania follows. Family Amboneuridae, new family SC terminating on costa well beyond mid-wing; RS arising slightly before mid-wing, with 5 terminal branches; M forked to about half its length; CUA coalesced with M basally, strongly convex, but terminating on the hind margin with a series of twigs; CUP strongly concave, not markedly close to CUA and slightly divergent from it distally. Cross veins very strong and preserved as prominent ridges over the wing surface, those between SC and R1 and between R1 and RS mostly transverse; in other areas the cross veins have frequent anastomoses, forming a very coarse, irregular net-work. ■Sharov (1966), however, believed that the Caloneurodea were endopterygote insects related to the Neuroptera. 112 Psyche [Vol. 87 This family differs from others in the order by the remoteness of CUA from CUP, and by the presence of irregular cells formed by cross veins in several areas of the wing. The closest affinities of the family seem to be with the Permobiellidae. Amboneura, new genus Since only one species is known in the family, a precise generic diagnosis is impossible. Some of the features mentioned below, such as the nature of the forks of the main veins, are probably of generic value. Type-species: Amboneura klosei, n.sp. Amboneura klosei, n.sp. Figures 2 and 3A Length of wing, as preserved, 25 mm; maximum width, 8 mm. Estimated length of complete wing, about 30 mm. R2+3 forked to about one-third of its length; R4+5 forked very shortly after its origin; R4 forked to about half its length, R5 unbranched. Type: No. 11027, in William Penn Memorial Museum, Harris¬ burg, Pennsylvania; collected by William F. Klose II (Field no. K6340) in Blythe Township, Pennsylvania; strip mine east of telephone poles 55—56, St. Clair-Mahanoy City Road. Allegheny Series of Pennsylvanian Period; Llewellyn Formation underclay. Buck Mt., #5 coal. This specimen consists of a nearly complete wing, lacking only the basal fifth; the coastal margin is broken away from the base to mid-wing. The rest of the wing is clearly preserved, with distinct convexities and concavities. The generic name is derived from the classical Greek words ambon (ridge) and neura (nerves), referring to the ridged cross veins, and is considered neuter plural. The species is named for William F. Klose II, the collector of the specimen, in recognition of his extensive fossil collecting and other aspects of field work done in the coal beds of Pennsylvania. I have placed this insect in the order Caloneurodea because of the general venational pattern of the wing and the nature of the cross veins. In most respects the venation is strikingly similar to that of Permobiella (figure 3B), from the Permian of Kansas, and to Caloneurella (figure 3C), from the Upper Carboniferous of Pennsyl¬ vania. In these two general, RS has only three terminal branches, 114 Psyche [Vol. 87 instead of five as in Ambononeura; however, in the other members of the order the branches range from two to six. As in nearly all genera, M has a single, prominent fork. CUA arises from the base of M, just before the level of origin of RS, and is slightly curved as it runs toward the hind margin, ending somewhat vaguely in associa¬ tion with cross veins at the margin—a feature that occurs in many Caloneurodea, especially the Permobiellidae. The separation of CUA and CUP is greater than in any other members of the order, although not much greater than in the Permobiellidae. The condi¬ tion in Caloneura itself is of interest in this connection; CUA and CUP are only slightly nearer together than the other veins are to their adjoining veins. The structure in Amboneura is probably the more generalized, since the ancestral stock of the order Caloneuro¬ dea presumably had a more normal venational pattern than is present in most of the members of the order as we now know it. It may well be also that the reticulation of some of the cross veins is another generalized trait, since it is present in many Protorthoptera. The diagnosis of the Caloneurodea, given above, has been slightly changed to permit inclusion of Amboneuridae. I take this opportunity to discuss the relationships of Calo- neurella carbonaria Carpenter, 1934, the only other member of the order Caloneurodea recorded from the anthracite coal fields of Pennsylvania. This was originally placed in the family Caloneuri- dae, otherwise known only from the Commentry beds of France. At the time of the description of the genus, very few specimens of the order Caloneurodea had been found and their classification was very arbitrary. Since then the Commentry specimens have been revised and the number of known families, genera, and species has tripled. Under the revised definition of the Caloneuridae, Calo- neurella can no longer be placed in that family, but it can be appropriately assigned to the Permobiellidae. This family was based on the genus Permobiella from the Permian of Kansas (Tillyard, 1937) and was originally considered to be a subfamily of the Neuroptera. Martynov (1938), recognizing its affinities with the Caloneuridae, transferred it to the Caloneurodea, where it almost certainly belongs (Carpenter, 1943). The family has been character¬ ized by the relatively short SC, which terminates just beyond mid¬ wing; by the presence of 3 branches on RS, a deeply forked M, and a slight divergence of CUA and CUP distally (figure 3B). Pseudo- biella, the second genus in the family, shares these features. 1980] Carpenter — Carboniferous Insects 115 sc Figure 3. A, Amboneura klosei, n.sp. Drawing of holotype. B, Permobiella perspicua Tillyard, from Lower Permian of Kansas; drawing of fore wing, based on holotype, no. 15593, Peabody Museum. Length of wing as preserved, II mm. C, Caloneurella carbonaria Carpenter, from Upper Carboniferous of Pennsylvania; drawing of wing, based on holotype, no. 6894/6895, Carnegie Museum, Pittsburgh. Length of wing, as preserved, 155 mm. SC, subcosta; M, media; CUA, anterior cubitus; other lettering as in figure 1. Caloneurella carbonaria has the basic venation of the Permobiel- lidae (figure 3C), except for the structure of SC, which extends well towards the apex of the wing. However, in view of the very close resemblance of Caloneurella to the Permobiellidae in all other respects, so far as known, I now believe the length of SC to be a character at the generic level instead of at the family level and I am placing Caloneurella in the Permobiellidae. Orders Protorthoptera and Blattaria There is one wing fragment in the Klose collection that is of unusual interest, although it is too incomplete for determination even to order. This is specimen No. 11035 (K6339), now in the William Penn Memorial Museum, from strip mine east of telephone poles 55—56, Blythe Township, under clay of Buck Mt. #5 anthra¬ cite (figure 5). It consists of the distal portion (12 mm long) of a wing with a venation that suggests the Caloneurodea. However, the nature of M, CUA, UP, and 1A indicates that the wing was almost certainly very short and broad, in contrast to the wings of the 116 Psyche [Vol. 87 Figure 4. Drawing of specimen no. 11035 (K6339), order uncertain, from Upper Carboniferous of Pennsylvania, near Trenton. Length of wing fragment, 13 mm. Lettering as in figure 3. Caloneurodea, which were long and slender. It is conceivable that this fossil might be part of a nymphal wing of a protorthopteron or possibly of a caloneurodean. One specimen, No. 11030 (K6343) in the William Penn Memorial Museum, clearly belongs to the Protorthoptera. It was collected in a strip mine along strike, 500 meters west of Blue Coal Braker, Audenreid Village, Pennsylvania, and under clay of unnamed anthracite, 85 feet above Mammoth anthracite. It consists of the distal half of a fore wing, partially covered by plant fragments (figure 6). The venation is clear enough over the preserved part of the wing, which is 25 mm long, but since only Rl, RS, and part of M are preserved, naming the species seems pointless, especially since family determination is impossible. The fossil is of interest, how¬ ever, because it is only the second insect from the anthracite coal field of Pennsylvania that can reasonably be placed in the order Protorthoptera. The other species is Hapaloptera gracilis Hand- lirsch (see Carpenter, 1965). The Blattaria, as mentioned above, are by far the most numerous insects in the coal beds. Of the 45 roaches in the collections being studied, 21 are small fragments of fore or hind wings, and nothing can be done with them below the ordinal level. The remaining 24 specimens fall into the families Archimylacridae and Mylacridae, there being 12 in each family. 1980] Carpenter — Carboniferous Insects 117 Figure 5. Photograph of protorthopteron, no. 11030 (K6343), William Penn Memorial Museum, from Upper Carboniferous of Pennsylvania, near Audendried Village. Length of wing fragment, 25 mm. The well-known variability of the venation within species of the Blattaria, both existing and extinct, makes the taxonomy of the fossil roaches, at least of the Palaeozoic species, very difficult, especially since the earlier workers on these fossils did not take the variation into consideration during the course of their studies. Recently, Dr. Jorg Schneider of the Bergakademie Freiberg, DDR, has undertaken a series of studies on Palaeozoic roaches (1977, 1978a, 1978b, 1980), with revised concepts of species, genera, and families. A great deal of specific synonymy seems likely, with perhaps as many as 80% of the species described from some deposits being placed in synonymy, and with extensive generic synonymy. For this reason and because all of the specimens in the collections at hand consist of wings, without body parts, I have not attempted generic identification. Some of the wings are very well preserved, however, and could be of special interest in connection with revisional studies, such as those being done by Dr. Schneider. Five specimens in the Klose collection are well preserved: No. 11044 (K7944) is a large fore wing of an archimylacrid, 50 mm. long, collected at Oneida, roof of Mammoth anthracite, Pennsylvania; 118 Psyche [Vol. 87 No. 11048 (K12092) is a small but excellent fore wing of an archimylacrid from Wanamie, Pennsylvania, roof of top split Baltimore anthracite; No. 11025 (K6345) 2 is the wing of a small mylacrid, from Carbondale, Pennsylvania, roof of Clark anthracite; and No. 11024 (K6334) is a specimen of a mylacrid, consisting of both fore wings and part of a hind wing, from Wanamie, Pennsyl¬ vania, roof of top split Baltimore anthracite. Acknowledgments Partial financial support of this research is gratefully acknowl¬ edged to the National Science Foundation, Grant No. DEB- 8004161, F.M. Carpenter, principal investigator. I am also indebted to Mr. William F. Klose II, for arranging the loans of these specimens; to Dr. Donald Hoff, Curator of Earth Sciences, William Penn Memorial Museum, Harrisburg, Pennsylvania, and Mr. Bruce Dietrich, Director of the Reading Public Museum and Art Gallery, Reading, Pennsylvania, for their cooperation in making the loans; and to Mrs. J. S. Lawless, Peabody Museum, Yale University, for the loan of the type of Permobiella perspicua. Carpenter, F.M. Literature Cited 1934. Carboniferous insects from Pennsylvania in the Carnegie Museum and Museum of Comparative Zoology. Ann Carnegie Mus 122:323—341. 1943. The Lower Permian insects of Kansas. Part 9. The orders Neuroptera, Raphidiodea, Caloneurodea, and Protorthoptera (Probnisidae), with additional Protodonata and Megasecoptera. Proc Amer Acad Arts Sci 75:55-84. 1960. Studies on North American Carboniferous insects. 1. Protodonata. Psyche 67:89—110. 1961. Studies on Carboniferous insects from Commentry, France. Part III. The Caloneurodea. Psyche 68:145—153. 1965. Studies on North American Carboniferous insects. 4. The genera Metropator, Eubleptus, Hapaloptera, and Hadentomum. Psyche 12:175-190. 1970. Fossil insects from New Mexico. Psyche 77:400—412. Carpenter, F. M. and E. S. Richardson, Jr. 1971. Additional insects in Pennsylvanian concretions from Illinois. Psyche 78:267-295. 2 The counterpart of this includes the specimen of the Dictyocicada- like insect mentioned above. 1980] Carpenter — Carboniferous Insects 119 Handlirsch, A. 1906. Revision of American Palaeozoic insects. Proc U S Nat Mus 29:661—820. 1911. New Paleozoic insects from the vicinity of Mazon Creek, Illinois. Amer Journ Sci 31:297—326. 1929. Insecta, in Kukenthal, Handbuch der Zoologie, 4(7):687-691. W. Gruyter. 1937. Neue Unterschungen iiber die fossilen Insekten mit Erganzungen und Nachtragen sowie Ausblicken auf phylogenetische, paleogeographische und allgemain biologische Probleme. I. Ann Naturhist Mus Wien 48:1-140. Martynov, A. V. 1938. Eutdes sur l’histoire geologique et de phylogenie des ordres des insectes (Pterygota) 1. Palaeoptera et Neoptera-Polyneoptera. Trav Inst Paleon Acad Sci USSR 7:1-119 [Russian], Rohdendorf, B. B., et at. 1962. [Insecta]. Osnovy Paleontologii: Akademii Nauk SSSR, pp. 1-374. [Russian], Schneider, J. 1977. Zur Variability der Fliigel palaozoischer Blattodea (Insecta), Teil I. Freib Forsch C 326:87—105. 1978a. Idem. Teil II. Freib Forsch C 334:21-39. 1978b. Zur Taxonomie und Biostratigraphie de Blattodea (Insecta) des Karbon und Perm der DDR. Freib Forsch C 340:1-152. 1980. Zur Taxonomie der junpalaozoischer Neorthoblattinidae (Insecta, Blattodea). Freib Forsch C 348:31—39. Sharov, A. G. 1966. The position of the orders Glosselytrodea and Caloneurodea in the system of insects. Paleon Zhur 1966:(3):84 93. Tillyard, R. J. 1937. Kansas Permian insects. Part 17. The order Megasecopteraand additions to the Palaeodictyoptera, Odonata, Protodonata, Protoperlaria, Copeognatha, and Neuroptera. Amer Journ Sci 33:81—110. LIFE HISTORY OF DYSODIA SICA (LEPIDOPTERA: THYRIDIDAE) IN PANAMA 1 By Annette Aiello Smithsonian Tropical Research Institute P.O. Box 2072, Balboa, Panama Thyrididae is a widespread tropical and subtropical family of moths, generally thought to be related to the Pyralidae, from which they differ in a number of ways (see Whalley, 1971). Possibly the group is not monophyletic, but so little is known concerning the immature stages, that few conclusions can be reached regarding the relationships among the four subfamilies. Dysodia (Thyrididae: Pachythyrinae) is a pantropical genus found on all continents except Australia (Whalley, 1971). Aside from scattered foodplant records for several species, little is known about the immature stages of any of the approximately thirty species. The present paper describes the egg, larvae, pupa, and larval behavior of Dysodia sica Druce (Figure 1) reared on Barro Colorado Island (BCI), Panama, during May through August 1977 and 1980. Seven other species of Dysodia are listed for BCI by Forbes (1942). Adult Behavior Adults of Dysodia spp. fly during early evening, and are seen frequently at lights on BCI. At rest, the wings are horizontal to the substrate, with the fore wings almost completely covering the hind wings (Figure 2). This resting posture, triangular in outline, is also common among many pyralid moths. When alert or about to fly, the fore wings are drawn forwards, exposing the hind wings, and bringing the markings of the fore and hind wings into alignment (Figure 3). The two “windows” on each hind wing show just behind the posterior margin of the fore wings. The fore wings are curved longitudinally so as to be somewhat concave above. 'Manuscript received by the editor December 4, 1980. 121 122 Psyche [Vol. 87 Figures 1-3. 1. Dysodia sica adult female (Lot 80-2). 2. Adult female (Lot 77-17) in triangular resting posture. 3. Same individual in wing-spread resting posture. 4. Same individual as final instar larva shortening for pupation. Scales = 5 mm. Foodplants Foodplant records for Dysodia are few (Table 1), and involve several unrelated plant families. Dysodia sica on BCI was found on two species of the Piperaceae: Piper marginatum (Figure 5) and Pothomorphe peltata (Figure 6). Both species are abundant weeds in the Laboratory Clearing, and have similar leaf texture, odor, and growth form. Immature Stages Egg Eggs (Figure 10) are deposited upon the upper surface, near the center of larval host plant leaves. Normally only one egg is laid per leaf. However, several leaves on a plant may receive them. Eggs are yellow-orange, cylindrical, 1.5 mm tall and 0.9 mm in diameter. They have a circle of 16-20 papillae around the periphery of the top. Except for a smooth area in the center of the top, Table 1. Larval foodplants reported for Dysodia species. Aiello - Life History of Dysodia sica 123 */-> r*-) ON ON <U <D £ Z3 =2 O o o Ji -a -a o CQ CQ U < < CQ B ^ ca 'f '■§ M g £ . D a< g .2 < a. — D ~ O U U ~ t/3 cd (5 (5 c ! II.I.III S U O 0 . Ce U J § S, 2 a, 2 2 ^ ^ •5 > O .*0 2 2 <3 Q Ci, O <J ^ -s: CL, a a o q > C C CS .§> .§> § .a .a a .a .g .2 .2 S3 ^ ^ ^ ^ ^ "S o o o o o o o Co <>3 Co 03 to ‘n >3 Q' 5' Q' Q' Q' Q' Q' <S o "^3 ^ 2 & 2 S §o *g * o ^ & on c C- <D . 6 « <u >, a q >, o X3 w ^ 5P Oh < 124 Psyche [Vol. 87 containing the micropyle, the surface is entirely covered with a reticulate pattern of hexagonal cells. Larvae Hatching The first instar larva eats its way through the egg apex 5-6 days after oviposition and consumes additional shell before attacking the leaf. Behavior After hatching, the larva constructs its first shelter by making a cut, about 1 cm long, perpendicular to the edge of the leaf. As it cuts, it rolls and crimps the cut portion of the leaf and fastens it in place with silk. The result is a conical chamber (Figure 7), closed at the top; open at the bottom. The chamber may be constructed on either the right or left edge of the leaf, and may be rolled over the upper surface or the lower surface of the leaf. Thus, four configurations are possible. As the larva feeds upon the inner layers of its shelter, it plugs the open end with frass and molted head capsules, probably as a barrier to intruders. Second and later instars turn and continue the cutting and rolling parallel to the leaf edge, until as much as half the perimeter of the leaf has been rolled (Figure 8). After consuming most of the rolled portion of the leaf, the larva moves to another leaf. Later larvae construct shelters beginning higher up on the leaf, often within a few centimeters of the attachment of blade and petiole. As a result, almost the entire leaf blade is rolled (Figure 9). Similar shelters have been described for Dysodia by past workers. Clemens (1860) noted that D. oculatana in eastern United States “. .. feeds... beginning on one side of a leaf to form a cone or cornet, cutting and rolling the separated portion, as it increases in size, sometimes across the entire leaf.” Forbes (1942), speaking of Dysodia spp. on BCI, commented “Larva forming a very messy and foul-smelling nest (whence the generic name). ...” Number and Duration of Instars There are five larval instars. Instar durations for seven reared individuals are given in Table 2. 1980] Aiello — Life History of Dysodia sica 125 Figures 5-10. 5. Leaf of Piper marginatum. 6. Leaf of Poihomorphe pellata. 7. Leaf roll made by first instar Dysodia sica. 8. Leaf roll made by fourth instar larva. 9. Leaf roll made by final instar larva. Scale = 23 mm. 10. Egg, showing portion of recticulate sculpturing. Scale = 0.25 mm. 126 Psyche [Vol. 87 Table 2. Number of days in each instar for the seven individuals in rearing Lot 80-55. PR = preserved, s = standard deviation, N = sample size. individual I 2 3 4 5 6 7 range mean s N egg 5 5 5 5 5 5 5 5 5 0 7 instar 1 2 2 3 2 2 2 2 2-3 2.14 0.38 7 instar 2 4 3 2 4 3 4 2 2-4 3.14 0.90 7 instar 3 2 2 3 3 3 3 3 2-3 2.71 0.49 7 instar 4 4 4 3 4 4 3 2 2-4 3.43 0.79 7 instar 5 9 11 9 9 10 9 9 9-11 9.43 0.79 7 pupa 70 PR 59 22 61 64 21 21-70 49.50 22.01 6 total days 96 — 84 49 88 90 44 44-96 75.17 22.60 6 total days non-diapause individuals 49 44 44-96 46.50 3.54 2 total days diapause individuals 96 84 88 90 84-96 89.50 5.00 4 sex 3 2 <3 <3 2 <3 <3 First Instar Upon emergence from the egg, the first instar larva has a black head (0.6 mm wide) and cervical shield. The prothorax just ventral to the shield is pink. The body is yellow-orange and has black setae and spiracles. After eating and expanding somewhat, the body becomes white and remains so through remaining instars. The arrangement of the head capsule setae is shown in Figure 11. All body setae are primary and are arranged as in the setal maps (Figure 12). Terminology used is that of Peterson (1962). Meso-and metathorax are identical except for the following differences: the spiracle on segment 8 is larger and is placed higher on the body than are those of the other segments. The/?/ group consists of one seta on segments 1, 7, 8, and 9; and two setae on segments 2-6. The crochets on the prolegs of abdominal segments 3-6 are uniserial and biordinal, and are arranged in a complete circle; those on segment 10 form a crescent on the anterior edge of the prolegs. The suranal plate bears eight setae (Figure 12). 1980] Aiello — Life History of Dysodia sica 127 Figures 11-14. 11. Head capsule of first instar. Scale = 0.125 mm. 12. Setal maps of first instar prothorax (P), meso- and metathorax (M), abdominal segment three (A-3), and first through final instar suranal plate (S). 13. Head capsule of final instar. Scale = 2 mm. 14. Setal maps of final instar prothorax, meso-and metathorax, abdominal segment three, and first through final instar abdominal segment nine (A-9). Later Instars Second through final instar larvae have black head and cervical shield. The body is white with black setae and spiracles. The arrangement of the head capsule setae is shown in Figure 13. Average head capsule widths for the five instars were 0.6 mm, 0.9 mm, 1.4 mm, 2.1 mm, and 3.2 mm for the seven individuals reared from eggs (Lot 80-55). The arrangement of the body setae in second through final instar larvae (Figure 14) is much the same as that of instar one, with the following differences: the three thoracic segments have one less seta on the leg base; the meso- and metathorax have seta theta present (absent in instar one); on the abdominal segments, seta mu is present (absent in instar one); the pi group consists of two setae on abdominal segments 1 and 7, three setae on segments 2-6, and one seta on segments 8 and 9 (cf. instar one); seta epsilon (absent in instar one) is vestigial. 128 Psyche [Vol. 87 The crochets and the suranal plate are as in instar one. The only other detailed description of a thyridid larva, is that by Heinrich (1921) for Meskea dyspteraria from Texas, U.S.A. It and Dysodia are similar, although Meskea has one more seta on the mesothorax ( Dysodia missing theta)', and on abdominal segment 9 (Dysodia missing eta). Pupation Three or four days before pupation, the larva stops eating and contracts somewhat (Figure 4). The body color changes from white to yellow. The pinacula bearing the setae become brown. The integ¬ ument is clear at this stage, and the peripheral tracheation can be seen clearly. Larvae in captivity made pupal chambers of leaf and silk. However, a survey of rolled Piper and Pothomorphe leaves in the Laboratory Clearing did not yield any pupae, so it is likely that the larva either abandons its plant to construct a cocoon elsewhere, or it forms a cocoon which becomes detached from the foodplant before pupation. Pupa The pupa (Figure 15) is obtect, dark brown, 14 mm long, and 6 mm wide. The maxillae extend to the caudal margin of the fore wings, and are 9 mm long. The prothoracic legs are about half the length of the fore wings; their femora are exposed between the protibia and the maxillae. The mesothoracic legs extend to the caudal margin of the fore wings. The antennae reach to within 2 mm of the caudal margin of the fore wings. The mesothoracic spiracle (between pro- and mesothorax) is larger than the abdominal spiracles. The pro-, meso-, and metathorax are 2 mm, 3.9 mm, and 0.9 mm wide respectively. The cremaster bears eight hooked setae. Heinrich’s (1921) illustration of the pupa of Meskea is similar, but the maxillae are only one third the wing length. Diapause and Eclosion Two of the six individuals (nos. 4 and 7) reared to adult had pupal periods of about three weeks (Table 2). The other four (nos. 1, 3, 5, and 6) entered diapause and remained as pupae for eight to ten weeks. The two non-diapause individuals completed their development (egg to adult) in 44 and 49 days, while the four diapause individuals 1980] Aiello — Life History of Dysodia sica 129 Figure 15. Pupa: ventral (V), lateral (L), and dorsal (D), views. Scale = 2 mm. completed theirs in 84, 88,90, and 96 days and thus emerged as adults at the same time as the next brood. All six adults eclosed during late afternoon. Broods Egg batches were first observed in May; additional batches appeared at intervals of about six weeks. Apparently there are several synchronous broods per wet season on BCI. Parasites A larva (Lot 80-77) collected 22 July 1980 was eaten by the larva of a tachinid fly. The fly larva formed a puparium inside the skin of its host on 27 July, and eclosed from the head end of the host skin on 15 August 1980. Four eggs were parasitized by wasps (unidentified) less than 1 mm long. Acknowledgements I would like to thank the Smithsonian Tropical Research Institute, Panama, for use of their facilities. Dr. Paul Whalley of the British 130 Psyche [Vol. 87 Museum (Natural History) for identification of the moth, and Dr. Robert Olberg for assistance with rearing. References Boisduval, M. J. A. 1829. Essai sur une Monographic de Zygenides, suivi du Tableau Methodique, des Lepidopteres d’Europe. xxvi + 132 pp., 8 pi. Bose, B. B. 1935. Life-histories of some Indian Thyrididae (Lepidoptera). Indian Journ Agric Sci, 5(6): 737-742. Clemens, B. 1861. Contributions to American Lepidopterology-No. 6. Proc Acad Nat Sci Philad, 1860: 345-362. Dyar, H. G. 1913. The American species of Dysodia. Insecutor Inscitiae Menstruus, 1(4): 37-45. Forbes, W. T. M. 1942. The Lepidoptera of Barro Colorado Island, Panama. No. 2. Bull Mus Comp Zool 90(2): 265-406, pi. 9-16. Heinrich, C. 1921. Some Lepidoptera likely to be confused with the pink bollworm. Journ Agric Res 20(11): 807-836. Mosher, E. 1916. A classification of the Lepidoptera based on characters of the pupa. Bull Ill State Lab Nat Hist, 12: 15-159, 27 pi. Peterson, A. 1962. Larvae of Insects: An Introduction to Nearctic Species. Part I. Lepidop¬ tera and Plant Infesting Hymenoptera. 315 pp. Ohio State University Press. Columbus, Ohio. Whalley, P. E. 1971. The Thyrididae (Lepidoptera) of Africa and its islands: a taxonomic and zoogeographic study. Bull Brit Mus Nat Hist Ent, Supplement 17: 1-198. USE OF ARTIFICIAL NESTS FOR REARING AND STUDYING POLISTES WASPS* By Stefano Turillazzi Istituto di Zoologia, Universita di Firenze, Italy Introduction Artificial honeycombs are habitually used in bee-keeping (Chauvin, 1968) but, to the best of my knowledge, such nests have never been used with social wasps. Recently the adoption of artificial nests was obtained in Polistes (Turillazzi et al., 1979) and the initial results of this study suggest that the technique could be of use in solving some problems regarding the social life of wasps. This paper describes the various kinds of nests used in rearing and studying Polistes. Materials and Methods Specimens of Polistes gallicus (L.) and a few P. omissus (Wey- rauch) were offered nests made of either plexiglas, glass, aluminium foil, plastic straws (4> 5 mm, length 15 mm) or gelatin capsules (d> 5.2 and 6 mm, length 13.4 and 15.2 mm, volume 0.3 and 0.4 cm 3 ). Paper materials, which the wasps could have easily destroyed or modified, were avoided. Adults were confined in a limited space with an artificial nest, in which larvae from a normal nest had already been transplanted, and this forced contact usually persuaded the wasps to adopt the nest. After a few hours the nest was transferred to a plexiglass cage (15 cm X side) and affixed with the axes of the cells approximately horizontal in order to prevent the larvae from falling out. Transplanted pupae were kept in place and also protected from being killed by the nurses, by a tissue-paper cover over the opening of the cell. The paper was then broken by wasps at emergence. Adoption was also obtained by substituting for a normal nest made directly in a plexiglas cage with an artificial one containing offspring from the former nest. In one instance, a foundress was removed from * Manuscript received by the editor October 10, 1980. 131 132 Psyche [Vol. 87 her newly-founded nest (4 cells) and confined in a small container with a few artificial cells (gelatin capsules) and no construction material. She laid her eggs directly in the artificial cells and continued to rear the larvae, the only time artificial cells were utilized without resorting to offspring transplant. Results and Discussion The adults solicit trophallactic exchanges just as soon as they find larvae within the artificial cells. The larvae were often pulled out of the cells and killed, usually because they had been damaged during transferring. A nest can be considered as adopted when all cannibalism has ceased, and at least one of the adults has begun to nourish the larvae normally with food placed in the cage. Some adults refused to return to the nest. A) Nests closely resembling natural nests A total of 21 nests, each formed of seven gelatin capsules, plus one of seven glass test-tubes (length 3 cm, filled with cotton to decrease their volume) (Fig. 1, 2) were affixed to the cages by wooden peduncles. Of 22 nests, 16 (73% including the glass “nest”) were adopted. The transparent walls allowed satisfactory observation of the adult-larva relationships and larval growth. The adults that adopted artificial nests did not substantially modify their behavior. The dominant female laid eggs without any difficulty in the artificial cells, placing as many as three in the larger capsules. Once the nest had been adopted, the cells were constantly licked, probably due to the lack of mouthing substance on the walls of the artificial cells. When furnished with paper, the wasps enlarged the artificial cells and contructed new ones, beginning in the dihedral angles formed by the walls of adjacent capsules. Additional cells were then constructed in contact with the natural rather than the artificial cells, with the result that the nest expanded in one direction—usually downward— in nests with horizontal cells (Fig. 1B). Cells with their axes oblique to those of the artificial cells, and not begun in the dihedral angles, were constructed without any peduncle near the mouth of one of the glass test-tubes (Fig. 2). The wasps continued to reinforce the artificial peduncle even though this was abnormally distant from the newly constructed cells. 1980] Turillazzi — Artificial Nests 133 Fig.l. Gelatin capsule nests. 134 Psyche [Vol. 87 Fig. 2. Glass test-tube nest. B) “Sandwich” nests Two nests, which I dubbed “sandwich”, consisted of two parallel glass slides 5 mm apart divided into cells by plastic partitions 5 mm apart (Fig. 3). The square entrance of the cells had no apparent effect on larval and adult behavior in the one nest adopted, and facilitated observation. These nests were affixed directly to the cage wall, without any peduncle or space behind the comb. On these, the nurses preferred the zone midway between the slides in direct contact with alveolar openings, while the less active females preferred the area between the top of the nest and roof of the cage. C) Re-use of artificial nests One sandwich and two capsule nests were re-used and enlarged the second year by foundresses born on the respective nests the preceding season. The sandwich nest, which had not been enlarged at all the preceding year, was noticeably expanded (Fig. 3B) after the artificial cells had been re-used to rear the first larvae. 1980] Turillazzi — Artificial Nests re-i 136 Psyche [Vol. 87 D) Flat nests with removable, interchangeable cells Two types were tested: one formed of transparent and opaque gelatin capsules inserted into holes drilled in the cage wall (Fig. 4), and one consisting of 80-82 plastic straws cells gathered in a plastic container which fit into a hole (</> 58 mm) in the cage wall (Fig. 5). Flat nests allow for the observation of individual larvae as each cell can be removed and controlled. Construction was prohibited in order to maintain the form and visibility of the artificial nests. The results obtained on these nests are shown in Table I. Nine out of 12 nests of Fie. 4. Flat gelatin-capsule nest before and during use. Fig. 5. Flat plastic-straw nest viewed from outside and inside the cage. 1980] Turillazzi — Artificial Nests 137 Table I. Flat nests (first and second type) with removable cells. Shown are the number and type of immature offspring transplanted, number of adults on the nest, nest acceptance (+ adoption, ± partial adoption, — refusal) egg-laying, larvaphagy, destruction of pupae by the adults, number of wasps emerged from larvae raised at least partially in artificial cells, and differences between wasps emerged and immature offspring transplanted. B C D E F G H I J K L 3 2 0 3 0 2 3 16 0 0 0 11 5 7 7 6 5 19 0 0 0 0 0 0 0 0 2 2 5 11 19 ± + + + + + + ± + + + + + + + + + 0 1 26 2 10 2 4 3 4 0 12 -14 - 6 + 19 - 9 + 3 - 7 - 5 -20 -20 -11 - 7 A B C D E F G H I J K L M N O P 2 6 10 4 6 4 5 6 6 10 11 9 6 12 51 7 0 0 0 1 12 0 0 0 0 0 0 0 2 0 0 1 4 4 5 3 22 14 + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + 24 20 3 21 55 2 0 0 0 0 0 59 0 0 27 12 + 21 + 6 - 7 + 14 +37 - 5 -13 -14 -15 +47 -13 -12 -24 + 4 138 Psyche [Vol. 87 the first type and ten out of 16 of the second type were adopted. Differences between the number of emerged individuals and trans¬ planted immature offspring were positive in two out of 12 nests of the first type and six out of 16 nests of the second type. However, the production of the artificial colonies—although lower—was occa¬ sionally comparable to that of natural ones [see Pardi (1951, p. 381) on 6 natural nests of P. gallicus ]. The growth curve of three larvae in a gelatin capsule nest attended by six wasps and kept at about 25° C, is shown in Fig. 6. Larval weight, registered daily by weighing the entire cell, varied initially due to the different quantity of honey accumulated in the cells, then followed almost identical curves during the period of greatest growth between the 11th and 19th day. A rapid decline in weight occurred immediately after pupation due in part to the emission of meconium and, perhaps, to water loss. E) Orientation of pupating larvae in transparent cells In natural nests each pupating larva first spins a silk dome over the open end of its cell, then turns back and spins the posterior end of the cocoon, returning finally to its original position. Some of the larvae raised in transparent cells failed to turn after spinning the posterior end of their cocoons and pupated without reorienting to the front of the cells. The effect of light on this orientation was tested by rearing larvae in three types of cell: transparent capsules illuminated from the side, capsules with opaque walls and transparent bottoms illum¬ inated from behind, and completely opaque capsules illuminated from the front. The results obtained with these nests, shown in Table II suggest the presence of a phototactic component in the orientation of the larva during pupal formation. Further tests are in progress to test for the presence of other components as well. F) Malformation of specimens emerged from artificial nests The shape and position of the wings in some newly emerged imagoes raised in gelatine capsules were so malformed as to prohibit flight. When raised in shorter-than-normal cells, the body was compressed cephalo-caudally (Fig. 7). Specimens reared in plastic straws cells seldom presented such anomalies. 1980] Turillazzi — Artificial Nests 139 WEIGHT (grams) 0.25 0 . 2 - 0.15 8 0.1 * O 0.05 8 * * * o o * oft * 2 8 T 29 DAYS Fig. 6. Larval growth curve (egg to emergence) obtained by daily weighing of three larvae in their artificial cells on a flat nest. Each symbol represents the weight of a single individual without the cell. Arrows indicate the day of pupation. 140 Psyche [Vol. 87 Table II. Pupal position in artificial cells. The data were analyzed with the x test of the null hypothesis that 100% of the larvae will pupate normally and 0% in the reversed position. position of pupa direction of cells illumination normal reversed Walls + bottom opaque front 19 2 N.S. Walls opaque, bottom transparent bottom 1 9 PC0.001 Walls + bottom transparent side 7 8 PC0.001 11 " . 1 11 II 11111 1 11 1U' A B Fig. 7. Females born from a normal (A) and gelatin-capsule nest (B). Acknowledgements I wish to thank Prof. L.Pardi for reviewing the manuscript and Mrs. S.Ferrati Berti for her help in the research. Literature Cited Chauvin, R. (sous la direction de) 1968. Traite de biologie de Tabeille. 5 vols. Masson, Paris. Pardi, L. 1951. Ricerche sui Polistini. 12. Studio della attivita e della divisione di lavoro in una societa di Polistes gallicus (L.) dopo la comparsa delle operaie. Arch.zool.ital. 36: 263-431. Turillazzi, S., S. Tonarelli and A. Ugolini 1979. Adoption of artificial nests in Polistes (Hymenoptera Vespidae). Moni- tore zool.ital.(N.S.) 13: 218. 1980] Erratum 141 ERRATUM.—Jackson, R. R. 1977. Comparative studies of Dic- tyna and Mallos (Araneae, Dictynidae): III. Prey and predatory behavior. Psyche 83: 267-280. The last line on p. 268 ( this species came from spending many hours observing a particular”) should be the last line on p. 269. Thus the text should read: “Most of the observations of feeding (88%) for this species came from spending many hours observing a particular web complex, located in a culvert through which a creek passed in the Chiracahua Mountains of Arizona.” FOR SALE Reprints of articles by W. M. Wheeler The Cambridge Entomological Club has for sale numerous reprints of Dr. Wheeler’s articles that were filed in his office at Harvard University at the time of his death in 1937. Included are about 12,700 individual reprints of 250 publications. The cost of the re¬ prints has been set at 5® a page, including postage; for orders under $5 there will be an additional handling charge of 50®. A list of the reprints is available for $1.00 from the W. M Wheeler Reprint Committee, Cambridge Entomological Club, 16 Divinity Avenue, Cambridge, Mass. 02138. Checks should be made payable to the Cambridge Entomological Club. CAMBRIDGE ENTOMOLOGICAL CLUB A regular meeting of the Club is held on the second Tuesday of each month October through May at 7:30 p.m. in Room 154, Biological Laboratories, Divinity Avenue, Cambridge. Entomolo¬ gists visiting the vicinity are cordially invited to attend. BACK VOLUMES OF PSYCHE Requests for information about back volumes of Psyche should be sent directly to the editor. F. M. Carpenter Editorial Office, Psyche 16 Divinity Avenue Cambridge, Mass. 02138 pSi ISSN 0033-2615 PSYCHE MUS. COMP. ZOOU. library AU6 2 8 1981 A JOURNAL OF ENTOMOLOGY RVARE3 founded in 1874 by the Cambridge Entomological Club Vol. 87 1980 No. 3-4 CONTENTS The Natural History and Behavior of the Bolas Spider, Mastophora dizzydeani sp. n. (Araneae). William G. Eberhard . Life History of Dismorpha amphiona beroe (Lepidoptera: Pieridae: Dis- morphinae). Annette Aiello . The Male of Echinolheridon (Araneae: Theridiidaef. Herbert W. Levi . New Species of Coniopterygidae (Neuroptera) from North America. Victor Johnson . Description of a New Wolf Spider in the Genus Pirata (Araneae: Lycosidae). C.D. Dondale and J.H. Redner . Stridulation by Workers of the Ant, Leptothorax muscorum (Nylander) (Hymenoptera: Formicidae). R. J. Stuart and P. D. Bell . Comparative Studies of Dictyna and Mallos: V. Tolerance and Resistance to Starvation. Robert R. Jackson . Notes on the Nests and Prey of Six Species of Pison in Australia. Howard E. Evans, Robert W. Matthews, and Allan Hook . The “Edge Effect” in Schizocosa ocreata (Araneae: Lycosidae): A Reassess¬ ment. Alan B. Cady, William J. Tietjen, and George W. Uetz . Differences in Nest Architecture Between the Neotropical Arboreal Termites, Nasutitermes corniger and Nasutitermes ephratae (Isoptera: Termitidae). Barbara L. Thorne . Synonymy of Archisolva Enderlein and Its Placement in the Stratiomyidae (Diptera). Norman E. Woodley . Observations on the Provisioning Behavior of Ammophila aberti Haldeman (Hymenoptera: Sphecidae). F. D. Parker, V. J. Tepedino, and D. L. Vincent . Review of the Coniopterygidae (Neuroptera) of North America, with a Revision of the Genus Aleuropteryx. Victor Johnson . A Nest of a Social Wasp, Vespa affinis, in Thailand (Hymenoptera: Vespidae). Thomas D. Seeley and Robin Hadlock Seeley . Generic Differences among the New World Spongilla-fly Larvae and a Description of the Female of Climacia striata (Neuroptera: Sisyridae). Raymond J. Pupedis . Two European Species of Chelostoma Established in New York State (Hymenoptera: Megachilidae). George C. Eickwort . 143 171 177 181 193 199 211 221 231 235 245 249 259 299 305 315 (continued on back coverf CAMBRIDGE ENTOMOLOGICAL CLUB Officers for 1980-1981 President .Jo Brewer Winter Vice-President .Barbara L. Thorne Secretary .Heather Hermann Treasurer .Frank M. Carpenter Executive Committee .William D. Winter, Jr. Ernest Leblanc EDITORIAL BOARD OF PSYCHE F. M. Carpenter (Editor), Fisher Professor of Natural History, Emeritus, Harvard University W. L. Brown, Jr., Professor of Entomology, Cornell University and Associate in Entomology, Museum of Comparative Zoology P. J. DARLINGTON, Jr., Professor of Zoology, Emeritus, Harvard University B. K. HOLLDOBLER, Professor of Biology, Harvard University H. W. Levi, Alexander Agassiz Professor of Zoology, Harvard University R. J. McGlNLEY, Assistant Professor of Biology, Harvard University Alfred F. Newton, Jr., Curatorial Associate in Entomology, Harvard University R. E. SlLBERGLIED, Associate Professor of Biology, Harvard University E. O. WILSON, Baird Professor of Science, Harvard University PSYCHE is published quarterly by the Cambridge Entomological Club, the issues appearing in March, June, September and December. Subscription price, per year, payable in advance: $11.00, domestic and foreign. Single copies, $3.50. Checks and remittances should be addressed to Treasurer, Cambridge Entomological Club, 16 Divinity Avenue, Cambridge, Mass. 02138. Orders for missing numbers, notices of change of address, etc., should be sent to the Editorial Office of Psyche, 16 Divinity Avenue, Cambridge, Mass. 02138. For previous volumes, see notice on inside back cover. IMPORTANT NOTICE TO CONTRIBUTORS Manuscripts intended for publication should be addressed to Professor F. M. Carpenter, Biological Laboratories, Harvard University, Cambridge, Mass. 02138. Authors are expected to bear part of the printing costs, at the rate of $27.50 per printed page. The actual cost of preparing cuts for all illustrations must be borne by contributors: the cost for full page plates from line drawings is ordinarily $18.00 each, and for full page half-tones, $30.00 each; smaller sizes in proportion. Psyche, vol. 87, no. 1-2, for 1980, was mailed April 27, 1981 The Lexington Press, Inc., Lexington, Massachusetts PSYCHE Vol. 87 1980 No. 3-4 THE NATURAL HISTORY AND BEHAVIOR OF THE BOLAS SPIDER MASTOPHORA DIZZYDEANI SP. N. (ARANEIDAE) By William G. Eberhard 1 Smithsonian Tropical Research Institute and Departamento de Biologia, Universidad del Valle, Cali, Colombia Introduction The unusual hunting techniques of the bolas spiders of the tribe Mastophoreae ( Mastophora, Dichrostichus, and Cladomelea) were described long ago (Hutchinson 1903, Longman 1922, Akerman 1923). These spiders make a large sticky ball on the end of a short thread, and swing the ball at passing insects while hanging on another short, horizontal “trapeze” line. Probably because the spiders are difficult to find, however, little has been done since to solve the problems which these first observations raised. Gertsch (1955) gives a complete and clear resume of what had been discovered of the biology of the entire group to that date. A recent study of an undescribed species of Mastophora which included observations of the behavior of both the spider and its prey plus extensive series of prey has finally confirmed the suspicion of the early naturalists that Mastophora lures its prey with a volatile substance which mimics the sex attractant pheromone of virgin female moths (Eberhard 1977). The present paper gives a taxonomic description of the species on which this work was done and presents ‘Present address; S.T.R.I. and Escuela de Biologia, Universidad de Costa Rica, Ciudad Universitaria, Costa Rica. Manuscript received by the editor December 22, 1980. 143 144 Psyche [Vol. 87 further observations on other aspects of its natural history and behavior, including web forms and their construction, the structure and function of the sticky ball, variations in prey species, egg sac construction behavior, and rates of egg sac production. These observations seem to link Mastophora to both araneids such as Cyrtarachne, Poecilopachys, and Pasilobus which spin more nearly typical orb webs, and to the completely webless Celaenia and Taczanowskia. Methods and Study Sites The main study site and the observation methods are described in Eberhard, 1977. The spiders were sedentary, seldom moving more than 10-20 cm in a night and usually returning day after day to the same daytime resting site where a pad of silk gradually accumulated. These sites were extremely exposed; one was on the barb of a barbed wire, and others were on fence posts, the upper surfaces of leaves, etc. in an open field. During the day in Cali the spiders sometimes experienced temperatures of up to at least 42° C combined with brisk (>10 kmph) winds. Additional observations were made in open areas near the edge of Lago Calima (el. 1400 m) in grassland with scattered small bushes and trees, where spiders were relatively common in September, 1977, but absent in January, 1979.. Unless otherwise noted, all descriptions of behavior refer to observations of mature females. Mastophora dizzydeani new species Figure 1-9 Dr. Willis Gertsch kindly studied male and female specimens, and stated (in litt.) that “I am confident that it represents an undescribed species. Like Dr. Gertsch, I have been unable to match this species to any published description, and keeping in mind the overworked state of most spider taxonomists plus the parasitic relationship which behaviorists and ecologists generally enjoy with them, will undertake the description of this new species. Etymology. Since this spider’s livelihood depends on throwing a ball fast and accurately, it seems appropriate to name it in honor of one of the greatest baseball pitchers of all time, Jerome “Dizzy” Dean. All measurements in mm; colors in parenthesis from living spiders. 1980] Eberhard — Bolas Spider 145 Female: The measurements of the holotype female from Cali, Colombia, are as follows: total length 15.32, carapace 5.44 long, 6.29 wide; abdomen 10.78 long, 15.99 wide (Figs. 1-3). Carapace mahogany brown, darkest on sides and the posterior declivity, without noticeable hairs. Sternum yellow-brown in central areas and brown at margins; labium and endites brown with white on margins nearest mouth; coxae and legs brown, the first leg weakly annulated with two bands of light color on femur, three on tibia, and two on metatarsus, similar markings on other legs. Abdomen Figs. 1-9. Mastophora dizzydeani new species. 1. Female cephalothorax, anterior view without appendages. 3. Female, dorsal view without appendages. 2. Female, lateral view without appendages. 4. Epigynum, subcaudal view. 5. Male, dorsal view without appendages. 6. Male, right leg I dorsal view. 7-9. Male palpus. 7. Ventral view. 8. Lateral view. 9. Dorsal view 146 Psyche [Vol. 87 yellowish (white) with a greyish-brown (dark green with brown tinge) band across the anterior margin with grey (dark green) on the anterior margins of the shoulders and a dark band extending to base; irregularly shaped intercalations of white along the anterior margin of the band. Three pairs of sclerotized depressions (in addition to many scattered minor ones) of which the first pair between the humps is dark brown and more conspicuous. Venter of abdomen whitish (yellow) between epigastric furrow and the brownish spinnerets, with a darker central area. The carapace about as long as wide, widest posteriorly, rounded on the sides, the pars cephalica at the posterior eye row more than half as wide as carapace (3.42/6.34). Pars cephalica subtriangular as seen from side, the occipital horn bifurcate apically, separated by deep rounded depression, and greatest width of horns more than half of width of carapace. Pars cephalica with well developed warts and cones which are mostly restricted to this area of carapace. Lateral eyes of each side on a single projecting cone and the four median eyes on a single, less pointed elevation. Clypeus vertical, equal in height to about 3-4 diameters of anterior median eye. Anterior eye row slightly procurved, posterior row slightly more so. Anterior medians sepa¬ rated by 2.3 diameters, posterior medians by 3.3 diameters; anterior medians from anterior laterals by 8 diameters, posterior medians from posterior laterals by 8.7 diameters. Median ocular quadrangle broader than long (ratio 1.49:1) and front eyes larger. Chelicerae bluntly conical, the upper margin with three sharp teeth, the middle one longest, lower margin with one tooth. Sternum subtriangular slightly longer than wide (ratio 1.13:1), broadly emarginate in front with rounded point opposite the posterior margin of each coxa. Posterior coxae separated by 1/4 width of fourth coxa. Labium broader than long (ratio 2.12:1) with central point projecting somewhat at tip and extending to about 1/3 of distance to tips of parallel endites. Legs clothed with fine hairs. I II III IV Femur 5.33 4.27 2.83 4.07 Patella 2.92 2.53 1.49 1.94 Tibia 4.88 3.42 1.91 2.95 Metatarsus 5.05 3.09 1.71 2.67 Tarsus 1.40 1.01 .79 .73 Total 19.58 14.32 8.73 12.36 1980] Eberhard — Bo las Spider 147 First leg with metatarsus much thinner than tibia and slightly curved, median claws large and strongly curved. Abdomen broad and subtriangular as seen from above, shallowly emarginate anteriorly and broadly rounded on sides, presenting a pair of clearly defined but not large tubercles slightly posterior and median to the shoulder humps. Abdomen overlapping carapace about to the horns, highest just anterior to the tubercles and declining steeply behind, with the caudal portion rounded. Abdomen hairless except for ventral surface anterior to spinnerets. Deepness of wrinkles along sides related to how recently spider oviposited. Spinnerets with apical segments short and subconical. The epi- gynum is illustrated in Fig. 4. Male: Total length of holotype from Lago Calima, Valle, Colombia is 1.81; carapace .87 long; abdomen .91 long and 1.35 wide. Coloration of carapace brown (reddish orange) with longitudinal white stripe forming dorsal triangle, eyes lighter. Abdomen white with scattered small grey blotches at anterior dorsal margin. Three pairs of large sclerotized depressions present, and tubercles posterior to first pair and separated slightly more than the depressions. The palpus is illustrated in Figs. 7-9. Type Localities: Female holotype from field on Melendez campus of Universidad del Valle at southern edge of Cali, Colombia. Male holotype from field at eastern edge of Lago Calima, near Darien, Valle, Colombia. Distribution: Western Colombia in Departamento Valle del Cauca. 1000-1400m el. in western range of Andres. Other Records: mature female, other mature males, several juveniles from type locality of male holotype. Natural History and Behavior Web construction and prey capture The form of the bolas and its construction were basically the same in M. dizzydeani as those of M. cornigera as described by Hutchinson (1903) and Gertsch (1947). A number of details were different, however, perhaps due to species differences, and are described below. As the spider moved back and forth on the horizontal (trapeze) line prior to starting a bolas (Fig. 10a), she did not reinforce the line, but rather repeatedly broke it, and reeled up the old line as she payed out a new one behind, her body thus forming a bridge between the two lines. She often descended somewhat as she broke the line, and waved 148 Psyche [Vol. 87 Fig. 10. Construction of a sticky ball. A. Spider moves horizontally, waving her front legs actively in the space where she will produce and swing her bolas. Probably this behavior serves to sense the presence of objects which would interfere with hunting behavior. B. Spider hangs from the horizontal trapeze line and begins to pull sticky silk from her spinnerets onto the bolas line which is attached above to the trapeze line. C. Spider continues to produce sticky silk and the sticky ball grows. D. The last of the sticky silk has been produced and it is slowly absorbed into the ball as the ball hangs free. The spider then walks across the trapeze line, grasps the bolas line, and assumes the hunting posture. 1980] Eberhard — Bolas Spider 149 her front legs actively as she moved (Fig. 10a), perhaps in order to sense the presence of objects beneath her future hunting site. As she produced the ball of sticky material at the end of the bolas line (Fig. lOb-d), it did not seem that she swept viscid material along a central line, but rather that a line as well as viscid material was pulled out with her IV legs. This impression was confirmed by microscopic examination of completed balls which showed large accumulations of thread (below). About 80-100 pulls with alternating legs IV were performed before the ball was complete, rather than 16-20 as with M. cornigera. Typically the spider began with shorter and quicker strokes, and then slowed as the ball began to form. When the ball was finished, it appeared that the silk simply ran out rather than that the spider somehow cut the line with one leg IV. The production of a ball took only 1-2 minutes from start to finish. On several occasions spiders assumed predatory positions without balls (Fig. 11) some of these after a ball being constructed was experimentally removed or became stuck to a leg and was ingested; I assumed that these spiders were hunting since some moths ap¬ proached them, but I never saw a prey capture. Hunting without first making a ball seemed to be associated with particularly windy evenings, but no careful measurements were made. Smaller, immature spiders made balls less often. One female which was an estimated 3-4 moults from maturity was seen hunting both Fig. 11. A mature female M. dizzydeani in hunting position without a ball, with both legs I extended anteriorly (seen from the side and slightly below—drawn from a photograph). 150 Psyche [Vol. 87 with and without a ball; another slightly larger one hunted without; and numerous newly emerged spiderlings appeared to hunt without. Perhaps this tendency is related to the fact that drying out of the sticky ball (see Fig. 14 and below) would be a more serious problem for smaller spiders due to surface-volume relations. As noted in Eberhard (1977), hunting spiders generally positioned themselves on the trapeze line with their ventral surfaces downwind. Since the direction of the wind at the study site varied erratically, the spiders assumed angles varying from 0° to 90° with respect to the trapeze lines. On two occasions when the wind changed 180°, the spider responded by releasing the ball and changing her position to hold it with the other leg I, changing her orientation 180° as she did so. Both those spiders with balls and ones in hunting position without balls responded to my humming (but not to the high-pitched hum of an electronic flash), suggesting that sound was not sensed through the bolas line as suggested by Gertsch (1947). The responses were different however. Spiders with balls extended one or both legs I, especially the lower one which was generally either extended laterally to point straight down, or else “cocked” ready to swing the ball (see Fig. Id in Eberhard 1977). Occasionally they actually swung the ball with a quick ventral flick of the leg. Those without balls sometimes flexed their legs I quickly, and other times extended them, especially the lower of the two. Even in the absence of sudden noises spiders holding balls twitched and jerked their legs I almost continuously, especially the upper one, giving the impression that they were extremely alert. Although the upper leg I seemed to be in position to grab prey, this was not its function since photos of spiders in the act of swinging the ball (Fig. 12) show this leg held back and away from the prey. Despite the spiders’ extremely quick reaction time and tne relatively slow flight of approaching moths (Eberhard 1980), it was not easy for the spiders to hit them, and 12 of 21 strikes I observed were misses. Most of the moths left after a miss and apparently did not return. When a spider succeeded in hitting a moth, the ball always stuck tight despite the moth’s struggles, and the spider descended the line, embraced the moth with her legs, and bit it. After several seconds she released her hold and wrapped the prey with slow alternate strokes of legs IV. The prey was rotated slowly or (usually) not at all during the wrapping. The spider then ascended the line as she held the 152 Psyche [Vol. 87 prey with one leg IV, climbed onto the trapeze line, and turned the moth so its anterior end was at her mouth and fed. Several variations on this general scheme were observed. On some occasions a spider which had captured a moth did not feed immediately, but fastened it to the trapeze line, spun a new ball, and resumed hunting; in one case a spider had three prey on the trapeze line when she caught a fourth. Longman (1922) observed a Dichro- stichus magnificus which also temporarily stored prey on the trapeze line. In no case did I see an extended coating along the bolas line as has been observed with M. bisaccata (Gertsch 1955) and D. magnificus (Longman 1922), and only one of an estimated 60 balls observed was double. On one occasion however I saw an even stranger trap. One particularly warm and windless evening a spider had an unusually long trapeze line which had three different balls hanging from it. The spider was at one end of the trapeze in a predatory stance, and did not hold a ball. The spider soon ate the balls, and later the same night made a single ball and held it with one leg in the usual fashion. Balls were ingested if after a period of waiting no prey were captured; such lapses averaged 24 min (range 14-41, N=8). Usually the spider did not make another ball immediately after ingesting an earlier one, but rested immobile for up to an hour or more. The Ball Moths are difficult prey for web spiders to capture since their abundant and easily detached scales more or less insulate them from sticky traps (Eisner et al. 1964), and some araneids have evolved special attack behavior towards them to offset this defense (Robinson 1969, Robinson, Robinson and Graney 1972). It is thus surprising that M. dizzydeani was able to catch moths regularly with a sticky trap, and the structure and function of the sticky ball assume particular interest. The balls of M. dizzydeani were largely liquid. When touched to a piece of filter paper, a ball immediately wet an area two to three times its diameter and, to the naked eye, disappeared. When touched to a nonabsorbant object like a glass slide, the ball remained visible as a mass of jelly-like material surrounded by a pool of liquid (Fig. 13). That the ball’s wetness is essential to its stickiness was shown by taking a newly made ball away from a spider and letting it hang free at 1980] Eberhard — Bo las Spider 153 Fig. 13. The internal structure of a sticky ball (diagrammatic) which was lowered onto a glass slide, showing the apparent layers of material of different viscosities near the edges, and the mass of folded thread in the center (regularity of folding is overemphasized). 154 Psyche [Vol. 87 the hunting site for 90 minutes. At the end of this time its size was substantially reduced (Fig. 14—an estimated 40% loss of volume) and it was no longer sticky. The spiders’ ingestion of balls after about 30 minute intervals thus probably served to insure that the ball is sufficiently sticky. This agrees with Hutchinson’s observations of the balls of M. cornigera. The reduction in size contrasts with the almost complete lack of shrinkage of the balls of adhesive on the sticky spirals of the orbs of araneids such as Metazygia sp., Leucauge sp., Fig. 14. Shrinkage of a sticky ball due to evaporation: A. a freshly made ball; B. the same ball 90 minutes later. 1980] Eberhard — Bo las Spider 155 and Gasteracantha cancriformis (Eberhard in prep.), and again serves to emphasize the unusually fluid nature of Mastophora’s adhesive. Spiders never discarded balls, always carefully ingesting them even when they accidentally stuck to their own bodies (observed three times) or to nearby objects (observed once—to a cardboard wind¬ screen held near the spider). In addition to the obvious conservation of nutrients which this represents, it may also be important in the conservation of water, since the spiders sometimes go for long periods without drinking and also endure high temperatures at exposed sites during the day (above). Cursory examination of balls on glass slides showed that their internal structure was complex, and consisted of a mass of curled or folded fibers which was embedded in a viscous matrix which was in turn surrounded by a less viscous layer (Fig. 13). More refined observations by R. W. Work (pers. comm.) showed that the folded “spring” fibers are noodle-like ribbons which are nearly rectangular in cross section (Fig. 15), with only slightly rounded corners and slight bulges on their flat sides. He reports as follows: “The dimensions of two samples of these fibers from Mastophora dizzy- deani were 10.7 X 3.4/umand 10.0 X 3.2^™. A sample from a closely related species from Costa Rica gave 11.4 X 4.3 /xm. They are possessed of axial birefringence, being of the same order of magni¬ tude (0.005-0.007) in planes perpendicular to both thick and thin axes of their cross sections. In this way they differ markedly from the elastomeric baselines of the sticky spirals of araneid orb webs, which are birefringent in neither the non-extended nor extended states. It follows that the bolas throwing and recovery phenomena are not based on elastic properties. Rather, the combination of rectangular cross section (typical of a steel spring), folded or sinusoidal con¬ figuration while at rest, and axial molecular orientation (as evidenced by bifrigence) is the basis of the springiness. The spring fibers are also different from the fibers making up the line from which the ball was suspended since these latter, which are also birefrigent (values approximated .02-.03, typical for lines from the major ampullate glands of other arachneids), were round (4-5 pm in diameter) as is typical of other spider fibers. The details of the junction between the bolas and the suspension line could not be resolved, although it appears that spring fibers may be present in the ‘bundle’ near the end of the line.” 156 Psyche [Vol. 87 The ball lost most of its adhesiveness after a single long extension, but shorter extensions appeared to be reversible. In one case a ball taken from a spider was touched lightly against a nearby object and then pulled away gently. A small mass of “liquid” stayed on the object, and was connected to the ball by a thin, dry thread which was not sticky when touched. When I moved the ball several mm farther away more of the dry line was drawn out, and when I moved it back this line drew back into the ball. This was repeated several times with identical results. Probably the dry line was one of the folded threads, and its immediate withdrawal into the ball when tension was lowered was due to its tendency to resume a folded configuration. In other cases a greater quantity of material was stuck to an object and when the object was moved away the entire ball rather than a single thread stretched with it. Hutchinson (1903) saw similar extraction and withdrawal of line in M. cornigera (in this case the line was the bolas line from which the ball was suspended). The extensibility of the ball had an unsuspected consequence which was revealed in photographs taken as the spider swung at moths. As seen in Fig. 12, the ball stretched into a line during the Fig. 15. Micrograph of fibers inside a sticky ball of M. sp. near dizzydeani from San Jose Costa Rica, showing regular folding, and ribbon-like shape of the fibers (unmodified illumination of ball on a glass slide; 10/jm = 6.6cm, original magnification 250X). Photograph by R. W. Work. 1980] Eberhard — Bolas Spider 157 swing. The greatest extension observed amounted to about 3.5-4 cm. This change was completely reversible and the recovery was evidently very rapid. I never noticed any elongation after swings by spiders, nor was I able to see any elongation when I myself swung a newly-made ball and looked quickly after each swing. The significance of this property of the ball is probably that it increases the spider’s striking distance while maintaining between swings the compact ball form which is essential for quick and accurate strikes. Such use of spring¬ like action is unusual if not unique in animal structures. In summary, it appears that the ball may function in the following way. The low viscosity liquid is sufficiently wet and abundant to flow past the moth’s scales and reach a relatively large area of the cuticle below. The more viscous liquid forms the actual bond to the thread which sustains the moth’s weight, and the thread folded inside the ball functions to permit quick, reversible elongations which extend the spider’s striking range and perhaps also serves to hold prey once it is hit. Prey The prey caught by a given individual of M. dizzydeani are relatively constant, but, as shown in Table 1, there is variation between individuals even at the same site. Some but not all the differences might be due to differences in prey abundances at different times of the year, although casual observations suggest that this was not the case. Small spiders seem to differ radically from larger ones in prey identity, which is expected given the relatively large size of the larger spiders’ prey. Rates of prey capture were estimated from numbers of moths found in sticky traps placed under four mature females’ hunting sites; they were certain underestimates since several times I saw a spider feeding on a moth in the evening but found no prey in the trap the next morning (probably some prey were blown clear of the traps when they were discarded). A total of 204 moths was found after 100 spider hunting nights (nights dedicated to egg sac construction were not counted), giving an average of 1.85 moths per hunting night. Since the rates of egg sac production were determined for these same four spiders during the same period (23 sacs in 219 spider days), these data can be used to test the assumption on which Eberhard (1979) based calculations of prey capture rates—namely that spiders convert 1980] Eberhard — Bolas Spider 159 about 25% of the wet weight of prey captured into eggs. These M. dizzydeani captured an average of 15.7 moths per sac; and the average wet weights of moths and sacs were 59.2 (N=9) and 331 mg N=l) respectively. This gives 331 mg of eggs resulting from 931 mg of prey, or 35.6% of prey weight being converted into eggs. These figures are only approximate, especially in light of the small sample of egg sac weights and the underestimates of prey captured. They are close enough to the value used by Eberhard (1979) to encourage belief that the calculations made there are not wildly wrong. Egg Sac Construction Spiders ceased predatory activity as much as 24 hours before ovipositing. Egg sac initiation was seen three times, always between 0:00 and T.50. As illustrated in Fig. 16 there were three recognizable stages First the spider made a disc of greyish-white fluffy silk suspended from one side (Fig. 16a). She enlarged this by adding silk to the sides and bottom with a stereotyped dabbing movement: the spinnerets were touched to the edge of the disc, then legs IV lifted the disc up and away, then brought it back down; this cycle was repeated over and over, with several threads being drawn each time. After about five minutes of this the spider held the disc against her ventral surface where it received the ball of yellow eggs which slowly emerged (Fig. 16b,c). The oviposition took approximately five more minutes, and when the ball was complete the spider pulled the sides of the disc around it and fastened them together with more dabbing movements so that the eggs were sewn into a cradle of fluff. She then made more fluff by holding the suspension line with one leg I and slowly treadmilling on the ball, pulling her abdomen away after each attachment so that it “bobbed” back and forth. This then gave way to further treadmilling without the bobbing movement but instead quick (2-4/sec.) side to side dabs with the abdomen, and the sac began to acquire a smooth outline (Fig. 16d). Within 20 minutes after the eggs had emerged they were no longer visible except for a yellow glow inside the ever-thickening walls when they were illuminated. About 15 minutes later, as the spider continued her treadmilling, the sac began to darken. The final product (Fig. 16e) was somewhat variable with respect to color and details of form, but was very similar to the sacs of M. cornigera and M. bisaccata (Gertsch 1947, 1955). A thick stem which spread into a plane at the top supported a nearly spherical sac which had in some cases small excrescences near the 160 Psyche [Vol. 87 midline. The basic color was amber brown, but it was overlaid with irregular patches of first white and then more brown silk. Where white overlaid brown the color was white, but where brown overlaid white an intermediate light brown color was produced. The total result was that the sacs appeared to be covered with irregularly shaped and distributed patches of brown, light brown, and white. As with other Mastophora species (Gertsch 1955) strong lines (with a faint golden tinge) accumulated around groups of egg sacs. Fig. 16. Egg sac construction. A. Spider spins a loose mat of silk hanging at the end of a reinforced line. B. Mass of eggs begins to emerge. C. Mass has emerged further and is cradled by the mat of silk. D. Spider “treadmills” on sac which has now assumed a smooth outline. E. Finished sac. 1980] Eberhard — Bolas Spider 161 Individual females produced up to eleven sacs. The average time between sacs was 9.5 days (23 sacs; range 5-13 days). One representa¬ tive sac weighed 331 mg and had 826 eggs (.40 mg/egg). Newly emerged spiderlings In some Mastophora species males emerge from the egg sac already mature (Gertsch 1947, 1955), but this was not the case in M. dizzydeani. Males of this species emerged an estimated one to two moults from maturity. On several occasions I found spiderlings which had especially swollen abdomens apparently feeding on shrivelled unhatched eggs when I opened a sac. Some shrivelled spiderlings were also seen, and when masses of spiderlings were observed under the microscope I saw that a typical behavior that was associated with the periodic waves of activity that swept through the mass was to “lunge” ventrally one or more times with the chelicerae open and snap them shut. Cannibalistic feeding could result in the growth of spiderlings within the sac, and should be looked for in species like M. cornigera in which males normally emerge mature. A suggestion that such cannibalism occurs comes from Gertsch’s report (1947) that only about 150 spiderlings emerged from each sac of M. cornigera. Since this species is slightly larger than M. dizzydeani and thus almost certainly lays more rather than fewer eggs per sac (clutch size is strongly correlated with spider size in Araneidae Eberhard unpub.), and since M. dizzydeani lays on the order of 800 eggs per sac, it is likely that the 150 M. cornigera spiderlings resulted from a much larger number of eggs. The sexes of newly emerged spiderlings could be distinguished by the slightly swollen pedipalps of the males. The sex ratios of samples of spiderlings from three egg sacs were T.787, 1:1.09, and 1:1.49 male-female (373 spiderlings, total ratio 1:1.01). This approximation to 1:1 is similar to those found by Gertsch (1947) for M. cornigera and Lowry (in McKeown 1952) for D. magnificus. Spiderlings of both sexes had a row of strong bristles on the prolateral surfaces of the tibiae and metatarsi of legs I and II (Fig. 17) which seemed to be essentially identical to the spines on the same legs of mature males. The spines are apparently soon lost, however, since a third or fourth instar female lacked them. 162 Psyche [Vol. 87 Fig. 17. A third instar female spiderling showing the spines on the prolateral surfaces of the front two pairs of legs, Defensive behavior Bolas spiders are sometimes called “bird lime” spiders because of their supposed resemblance to bird droppings as they rest during the day. Once one has found a spider this resemblance seems a bit farfetched, but my repeated experience during daytime searches for spiders of finding a spider only to have it turn out to be a bird dropping suggest that the spiders’ coloring and resting posture (similar to that of M. cornigera —Gertsch 1947) do function to mimic bird droppings. M. dizzydeani did not attempt to flee when disturbed, but simply crouched immobile, even when picked up in the fingers. Gertsch (1947) observed the same behavior in M cornigera. When squeezed gently on the abdomen, M. dizzydeani produced a strong, somewhat disagreeable odor reminiscent of those of lampyrid beetles and 1980] Eberhard — Bolas Spider 163 canned string beans. When spiders were observed under the micro¬ scope it was clear that the odor was produced by the regurgitation of a drop of cloudy liquid at the mouth. When the disturbance had passed the spider sucked the liquid back in and cleaned its mouthparts and the smell vanished. Hutchinson (1903) also noted that disturbed M. cornigera produced an unpleasant odor which came from a drop at the mouth. Discussion Robinson and Robinson (1975) suggested, on the basis of their study of Pasilobus and Clyne’s work (1973) on Poecilopachys, that there is an evolutionary series starting with typical orb weavers and passing through Poecilopachys and then Pasilobus to the bolas spiders Mastophora, Dichrostichus, and Cladomelea. They estab¬ lished several links in web architecture and function between Poecilopachys and Pasilobus. The results of this study support this general scheme and indicate that the line can be reasonably extended through the bolas spiders to the webless araneids Celaenia and Taczanowskia. This series does not of course purport to demonstrate that any group is directly descended from any other, but rather refers to increasing specialization of prey catching behavior which diverges in this group of genera from the ancestral construction of typical orb webs. There are several points of similarity between these observations ol M. dizzydeani and the data available for Pasilobus sp. (Robinson and Robinson 1975), Poecilopachys australasia (Clyne 1973), and the related Cyrtarachne sp. (Eberhard unpub.): A. All actively pull sticky silk from their spinnerets while hanging more or less vertically below a horizontal thread (e.g. Fig. 4B in Robinson and Robinson 1975). This movement is similar to and was probably derived from the pulling movements many araneids make with legs IV as they lay sticky spirals (Robinson and Robinson 1975, Eberhard in prep.). The Robinsons were not certain that thread (as opposed to only vicous material) was being pulled out by Pasilobus, but from their description, personal observations of Cyrtarachne and Mastophora( above), and considerations discussed in Eberhard (1976 and in prep.), this seems to me to be likely. B The M. dizzydeani web which had several balls hanging from a 164 Psyche [Vol. 87 single horizontal thread is similar to a Pasilobus web: if one breaks the low-shear joints at the ends of Pasilobus spanning threads so that they hang from the midline, the webs are nearly identical. The web of Cyrtarachne sp. (Fig. 18) is very similar to that of Poecilopachys, as is its building behavior (Eberhard, unpub.). C Both M. dizzydeani females and Pasilobus catch moths almost exclusively. This specialization in M. dizzydeani is probably due to the use of moth sex attract pheromone mimics (Eberhard 1977), and it is possible that the same may be true for Pasilobus (Robinson and Robinson 1975). It is interesting to note that the tendency of Pasilobus to lay the frame lines by floating them downwind of the spider’s eventual resting site would make its nearly horizontal web lie downwind of the spider, and at least as long as the wind direction did not change this would be the direction from which moths being attracted chemically would be expected to approach. D Both M. dizzydeani and Pasilobus produce sticky silk which adheres firmly to moths, something which no other araneid is known to do. Their sticky silk seems to differ in that Pasilobus silk will stick repeatedly while that of M. dizzydeani loses most of its stickiness after the first contact. E Both M. dizzydeani and Cyrtarachne sp. release an unpleasant odor when handled, a characteristic unique among araneids and perhaps all spiders. Species of all four genera rest in very exposed sites during the day with their legs folded tightly around their bodies so their front legs cross under the anterior part of the cephalothorax, a posture unusual in araneids. In addition to these links between M. dizzydeani and Pasilobus, Poecilopachys, and Cyrtarachne, there are also behavioral links between M. dizzydeani and Celaenia and Taczanowskia: A All three seem to specialize as adults on male moths as prey (McKeown 1952, Eberhard in press). Capture of small flies by spiderling M. dizzydeani is also parallelled in Celaenia sp. since C. S. Lauder has found over 300 spiderlings of this species feeding — all on male psychodid flies (C. S. Lauder, pers. comm.). B Both Celaenia excavata and Taczanowskia sp. (Eberhard in press) seem to spin no web other than a single dry horizontal 1980] Eberhard — Bolas Spider 165 Fig. 18. Web of mature female Cyrtarachne sp. (scale marker—5 cm.). line, and M. dizzydeani also sometimes limit its spinning to this minimum and assumes a similar hunting posture. C The egg sacs of species in all three genera are more or less round and tear-shaped, with very strong outer layers (Gertsch 1955, McKeown 1952, Forster and Forster 1973, Eberhard in press), an unusual design for araneids. The construction behavior of Celaenia excavata (Lowry in McKeown 1952) is nearly identi¬ cal that of M. dizzydeani. 166 Psyche [Vol. 87 D Both Celaenia (Forster and Forster 1973) and Taczanowskia (Eberhard in press) adopt the same daytime resting posture as that of Mastophora. In sum, the data suggest that the traditional groups of Cyrtarach- neae (including Cyrtarachne, Pasilobus, Poecilopachys, and four other genera), Mastophoreae (including Mastophora, Dichrostichus, Cladomelea, and three other genera), and Celaenieae (including Celaenia and Taczanowskia ) (Roewer 1942) should be placed together in the same section of the subfamily Araneinae. It is reasonable to ask why natural selection would favor such radical reduction in trapping webs in this group. The use of volatile substances mimicking prey pheromones could make large traps superfluous, and one can imagine a gradual reduction in webs accompanying an increasingly precise mimicry. The development of an adhesive capable of restraining moths could also result in selection for simplified webs designed to maximize prey interception efficiency (Chacon and Eberhard 1980). It is not immediately clear however why an effective sticky trap like a bolas should be abandoned altogether as in Celaenia, Taczanowskia, and, on occasion, M. dizzydeani. It seemed that wind conditions may have influenced the type of trap M. dizzydeani used, since the most elaborate web (three balls) was made when the air was unusually still, and spiders apparently hunted without balls during particularly windy periods. Under windless conditions a more elaborate trap might be advan¬ tageous since 1) an attractant would diffuse in many directions and the direction from which prey might approach would be less certain, and 2) the sticky material would be especially effective since it would not dry out as quickly. On the other hand, strong wind (or relatively dry conditions of any sort, including relatively small body size) would make investment in sticky material which evaporated quickly less advantageous. As noted above, this line of reasoning could also explain the apparently greater frequency of hunting without balls in younger M. dizzydeani. This consideration may have consequences regarding the as yet unestablished trapping method of newly emerged M. dizzydeani. If my observations of spiderlings apparently hunting without a bolas are typical and correctly interpreted, then they may provide an explanation for the rows of bristles on the inner sides of the anterior legs of spiderlings (and incidently suggest that mature males, which also have these bristles, may feed after they mature; perhaps, as 1980] Eberhard — Bo las Spider 167 Gertsch 1947 suggests, they can live for extended periods). It is interesting to note that Celaenia, which hunt without a web, also have spines on their front pairs of legs (e.g. Fig. 24 in Forster 1967). In this case however the spines are on the ventral surfaces of the femur and tibia, and would seem designed to give the spider a more secure grip on prey that has already been seized (see however Lowry’s description in McKeown 1952 of spiders accepting prey held in forceps) rather than to increase the surface of the leg and thus presumably its ability to intercept prey as in small M. dizzydeani. The variety of prey captured by M. dizzydeani (Table 1) is not surprising, given the fact that different moth species have been found to use identical sex attractant chemicals (e.g. Silberglied 1976). It is however unexpected to see the differences in prey captured by different individuals of the same species and size at the same time and place. The spiders seem to be somewhat flexible with regard to prey, and this trait could obviously be advantageous if, as seems likely, a single prey species is not consistently plentiful. How the differences between individual spiders are produced is unknown. Although the data are meager, it appears probable that M. dizzydeani change pheromones as they mature, attracting larger species as they grow. This conclusion must remain tentative however pending more data on prey, proof that the other prey species actually produce and respond to different pheromones, and that the spiders attract them chemically. Perhaps the thick-walled egg sacs of Mastophora and its relatives serve to protect the young for extended periods so that they can emerge when particular prey species are abundant. The name “bolas spider” is firmly fixed in the literature, and I do not propose that it be changed, but it is worth noting that it is a misnomer for Mastophora. A bolas consists of a thong or thongs to which heavy balls are attached, and is thrown so that the thong wraps around the target, impeding its escape. The Mastophora trap is more sophisticated: it depends on the extraordinary stickiness of the ball rather than the entangling action of the line; it is swung rather than thrown at the prey; and the ball itself converts reversibly into a sticky line which increases the spider’s striking distance. A less picturesque but more accurate name would be “sticky yo-yo spider . Acknowledgements 1 thank R. Forster and C. S. Lauder for information on Celaenia, 168 Psyche [Vol. 87 Carlos and Olga Hobrecker for their hospitality at Lago Calima, A. J. T. Johnsingh and M. Gadgil for help and hospitality in India, Willis Gertsch for examining specimens of the spider, H. W. Levi for help with materials, R. W. Work for kindly examining specimens of the bolas and allowing me to use his photographs and unpublished data, H. Dahners for help with the moths, and M. J. W. Eberhard for a critical reading of the manuscript. Financial support was pro¬ vided by the Comite de Investigaciones of the Universidad del Valle, Cali, Colombia, and the Vicerectoria de Investigacion, Universidad de Costa Rica. Summary The form of the egg sac, variations in bolas construction and hunting technique, and other behaviors link Mastophora dizzydeani sp.n. to both reduced-orb weavers (Cyrtarachneae) and webless araneids (Celaeneae). The sticky ball is structurally complex, and includes both a substantial portion of volatile liquid and a mass of flattened, apparently spring-like thread; it elongates reversibly when it is swung. There was significant variation between individual spiders with respect to the species of moths that they captured. Adult females converted about 35% of the weight of their prey into eggs. They produce an unpleasant odor when handled. Newly emerged spider- lings apparently hunted without making a bolas, and preyed on small nematocerous flies. Males did not emerge already mature from egg sacs, and it may be that cannibalism within egg sacs accounts for the emergence of mature males in other species. Literature Cited Akerman, C. 1923. A comparison of the habits of a South African spider, Cla- domelea, with those of an Australian, Dichrostichus. Ann. Natal Mus. 5: 83-88. Chac6n, P. and W. G. Eberhard. 1980. Factors affecting numbers and kinds of prey caught in artificial spider webs, with considerations of how orb webs trap prey. Bull. br. arachnol. Soc. 5( 1 ):29 38. Clyne, D. 1973. Notes on the web of Poecilopachys australasia (Griffith and Pidgeon, 1883) (Araneida: Argiopidae). Aust. ent. Mag. 1: 23-29. Eberhard, W. G. 1976. Physical properties of sticky spirals and their connections: sliding connections in orb webs. J. nat. Hist. 10: 481-488. - 1977. Aggressive chemical mimicry by a bolas spider. Science 198: 1173— 1175. 1980 ] Eberhard — Bolas Spider 169 1979. Rates of egg production by tropical spiders in the field. Biotropica 11(4): 292-300. _ 1980. Spider and fly play cat and mouse. Nat. Hist. 89(1): 56-61. in press. Notes on the natural history of Taczanowskia sp. (Araneae: 1964. Adhesiveness of spider silk. Araneidae). Bull. br. arachnol. Soc. 5(4). Eisner, R., R. Alsop, and G. Ettershank. Science 146: 1058-1061. Forster, R. R. 1967. The Spiders of New Zealand. Part I. Otago Mus. Bull. No. 1: 7- 1 24. Forster, R. R., and L. Forster. 1973. New Zealand Spiders. London: Collins Gertsch, W. 1947. Spiders that lasso their prey. Nat. Hist. 56(4): 152-158, 189. Gertsch’, W. 1955. The North American bolas spiders of the genera Mastophora and Agatostichus. Bull. Am. Mus. nat. Hist. 106(4): 221-254. Hutchinson, C. E. 1903. A bolas-throwing spider. Sci. Am. 89(10): 172. Longman, H. 1922. The magnificent spider: Dichrostichus magnifies Rainbow. Notes’ on cocoon spinning and method of catching prey. Proc. roy. Soc. Queens- land 33: 91-98. McKeown, K. C. 1952. Australian Spiders. Sydney: Angus & Robertson. Robinson, M. H. 1969. Predatory behavior of Argiope argentata (Fabncius). Am. Zool. 9: 161-173. Robinson, M. H. and B. Robinson. 1975. Evolution beyond the orb web: the web ,of the’araneid spider Pasilobus sp., its structure, operation and function. Zool. J. Linn. Soc. 56(4): 301-314. Robinson, M. H„ B. Robinson, and W. Graney. 1972. The predatory behavior of the nocturnal orb-web spider Eriophora fuliginea (C. L. Koch) (Araneae. Araneidae). An. Primer Congr. Latinoam. Ent. Rev.peru. Enl. Agric. 14: 304- Roewer, C. F. 1942. Katalog der Araneae. Bremen, 1: 1-1040. Silberglied, R. 1976. Communication in the Lepidoptera. in T.A. Sebeok (ed.) How Animals Communicate. Bloomington, Ind.: Indiana Umv. Press, pp. 362- 402 . LIFE HISTORY OF DISMORPHIA AMPHIONA BEROE (LEPIDOPTERA: PIERIDAE: DISMORPHIINAE) IN PANAMA* By Annette Aiello Smithsonian Tropical Research Institute P.O. Box 2072, Balboa, Panama Dismorphia is a neotropical genus of butterflies related to the familiar ‘sulfurs,’ ‘whites,’ and ‘orange-tips’ common in temperate regions. They are of unusual interest due to the participation by adults, of certain species, in mimicry complexes. Indeed, Bates’ (1862) influential paper on mimicry was based upon this group of butterflies. Unfortunately, little is known of their immature stages or hostplant relations, and only one life history has been described in the genus to date (Young, 1972). The present paper reports on the immature stages and host plant of a second species. The following observations were made on Dismorphia amphiona beroe (Lucas) (Figure 1), reared from eggs, during 28 April through 4 June 1980 on Barro Colorado Island (BCI), Panama. On 28 April, during late morning, a female D. a. beroe in the BCI Laboratory Clearing, flew along the forest border in search of oviposition sites. Maintaining a distance of 30-60 cm from the ground, she touched down briefly upon the leaves of virtually every plant in her path, regardless of whether these were ferns, monocots, or dicots. Oviposition took place on one species only: Ingapezzizifera (Leguminosae), present as five plants (each about 1 meter tall) among the second-growth in the north-west corner of the clearing. Three eggs were laid upon the young leaves of this species, one per plant. Similarly, Young (1972) reported Inga pittieri as the foodplant of D. virgo (=£). zaela oreas. Vide Lamas (1979) page 21) in Costa Rica. Eggs The shiny eggs were 1.5 mm long, and 0.6 mm wide, were spindle- shaped, and had nine longitudinal ribs, and approximately 30 cross¬ ribs. Eggs were nearly invisible due to their strong reflection of the surrounding greenery. Larvae Hatching occurred during late morning, on 2 April (male) and 3 •Manuscript received by the editor March 13, 1981. 171 172 Psyche [Vol. 87 April (female); the third egg never hatched. Larval stemmata were visible through the chorion several hours before larval emergence. Neither larva was sacrificed, therefore detailed larval descriptions were not made. Both individuals passed through five larval instars, head capsule widths for which are shown in Table 1. First instars were yellow- green, but upon feeding, one day after hatching, they took on the same green color of their food plant. As reported by Young (1972), all instars rested on the undersides of leaves along veins exposed by larval feeding (Figure 2), and thus camouflaged, were very difficult to locate. Final instars (Figure 3) fed on older leaves and were a much darker green than were earlier stages. Figures 1-4. Dismorphia amphiona beroe (Rearing lot 80-42). 1. Adult male (above) and female (below), dorsal (left) and ventral (right) views. Scale = 15 mm. 2. Second instar larva (about to molt) resting on underside of leaf, along vein exposed by larval feeding. Scale = 3 mm. 3. Early final instar larva. Scale = 5 mm. 4. Male pupa several hours before eclosion. Scale = 5 mm. 1980 ] Aiello — Dismorphia amphiona beroe 173 Larval body segments were annulate, with four to six annulets each, and covered with numerous short secondary setae that gave a velvety appearance. On each of the nine spiracular segments, the spiracles were situated between annulets 2 and 3. First instars had long black setae on the head (5 pairs) and prothorax (2 pairs), and on abdominal segments 9(1 pair) and 10 (2 pairs.). On the prothorax, a third (lowermost) pair of long setae was pale. Later instars lacked either long or black setae. Second through fourth instar heads (Figure 5) had many more setae, and these were raised upon chalazae. While a few were simple slender setae, most were thick, with expanded truncate tips. Final instars had short thick, but pointed setae, also raised upon chalazae. The labrum was emarginate in all instars. Durations of the immature stages are shown in Table 2. During the late afternoon and early evening preceding pupation, the fifth instar larva prepared a silk girdle; ecdysis to the pupal took place later the same night. Table 1. Head capsule widths (mm) for the two reared individuals of Dismorphia amphiona beroe (Rearing lot 80-42). instar 1 2 3 4 5 $ 0.38 0.63 1.08 1.67 2.50 $ 0.42 0.67 1.08 1.67 2.50 Pupae The waxy green pupa (Figure 4) was spindle-shaped due to its tapered ends and the curved expansion of the ventral line of its body. The following measurements were made: total length of pupa (29 mm); dorso-ventral thickness of pupa at point where girdle crosses dorsum (6 mm); lengths of prothorax (2.5 mm), mesothorax (3.5 mm), metathorax (1.5 mm), median cephalic projection (5 mm), maxillae (16 mm), prothoracic tibia plus tarsus (8 mm), mesothoracic tibia plus tarsus (10 mm), antennae (15 mm), and mesothoracic wings (12 mm). The maxillae terminated at a point 1.5 mm before the wing apices. The metathoracic legs were covered except for their extreme tips. The 174 Psyche [Vol. 87 mesothoracic spiracle showed as a slit 1.5 mm long. The cremaster bore numerous hooked setae. Pupal waxy greenness persisted until one day before eclosion, at which time the adult wing pattern began to develop (Figure 4). Pupation lasted eight days for the male and nine days for the female; emergence took place near 9 am on 2 June (male) and 4 June (female). The two individuals reared, their egg shells, larval head capsules, and pupal skins, are in the author’s collection, labelled as Rearing lot 80-42. Figure 5. Larval head capsules: first instar (1-1), third instar (1-3), and fifth (final) instar (1-5). Scales = 0.15 mm, 0.30 mm, and 0.75 mm respectively. Table 2. Number of days spent in each stage by the two individuals of Dismorphia amphiona beroe (Rearing lot 80-42). inslar egg 1 2 3 4 5 pupa total 8 4 4 4 3 5 7 8 35 9 5 3 4 3 6 7 9 37 Acknowledgements I would like to thank the Smithsonian Tropical Research Institute, Panama, for the use of their facilities, Mr. Gordon B. Small for identification of the butterfly, and Dr. Robert Silberglied for helpful suggestions. 1980 ] Aiello — Dismorphia amphiona beroe 175 References Cited Bates, H. W. 1862. Contributions to an insect fauna of the Amazon Valley. Lepidoptera: Heliconidae. Trans Linnaean Soc London, 23(3): 495-566 + pi. 55-56. Lamas, G. 1979. Los Dismorphiinae (Pieridae) de Mexico, America Central y las Antillas. Rev Soc Mex Lepid, 5(1): 3-37. Young, A. 1972. Notes on the life cycle and natural history of Dismorphia virgo (Lepidoptera: Pieridae: Dismorphiinae) in Costa Rica. Psyche, 79(3): 165-173. =D. zaela oreas (Salvin). Vide Lamas (1979) page 21. THE MALE OF ECHINOTHERIDION (ARANEAE: THERIDIIDAE)* By Herbert W. Levi Museum of Comparative Zoology, Harvard University Cambridge, Mass. 02138 Introduction. A genus based on specimens of one sex only is unsatisfactory, even when the available specimens are so distinctive as to demand description. The four described species of the genus Echinotheridion all are known from females only. It therefore is important to describe the male recently found, the more so in view of his remarkable features. I would like to thank Norman Platnick, who found the male in American Museum of Natural History collections and recognized it as a possible male of Echinotheridion. Echinotheridion are small theridiid spiders, 2 to 3 mm in total length. The carapace is like that of Achaearanea and Theridion. The anterior median eyes of the known species are larger than others less than their diameter apart, almost touching the laterals. Eyes of the posterior row are equally spaced. Chelicerae are small with two anterior sclerotized teeth. Legs are short, the first longest. The abdomen is suboval, higher than long (Levi, 1963, fig. 120). There is no colulus. As in specimens of Tidarren, there usually is a vertical white line just above the spinnerets. Unusual for theridiid spiders is the enormous sclerotized epigynum. Overhanging the epigynum are coxal spurs which appear to be a functional part of the structure (Levi, 1963, fig. 120). Coxal spurs are otherwise uncommon in female theridiid spiders. Four species are known, three new in 1963: E. cartum from southern Brazil, E. elicolum from Venezuela, E. otlum from Ecua¬ dor, and E. utibile (Keyserling) from the Amazon. The recently collected male comes from within the range of E. cartum and probably belongs to that species. The male is remarkable in having only one palpus, and this ot enormous size, similar to males of Tidarren. Upon attaining adult¬ hood, Tidarren males attach one of their two palpi to a silk web and twist it off (Branch, 1942). * Manuscript received by the editor April 2, 1981 111 Figs. 1,2. Echinotheridion cartum. 1. Male, scale line 1.0 mm. 2. Left palpus, scale line 0.1 mm. The second unusual feature is the highly modified cymbium (Fig. 2): two ends are drawn out into spines, while another side is pulled out and apparently supports the cymbium. Because the individual has only one palpus, I did not dissect or expand it, so the homology of the structures is not understood. An embolus can be seen below the lateral extension (on the right in Fig. 2). Unlike the female, the male has no spurs on the fourth coxae and has no other leg modifications. If the modified cymbium and the white mark above the spinnerets (Fig. 1) are synapomorphies, one must consider the genus related to Achaearanea and Tidarren. Psyche [Vol. 87 Echinotheridion cartum Levi Figures 1 and 2 Echinotheridion cartum Levi, 1963: 236, figs. 117-121, $, Map 3. Female holotype from Apa [River] Paraguay, 1908-1909 in the American Museum of Natural History. Description. Male. Carapace golden yellow with dusky marfcs, darker on sides. Sternum gray. Legs dusky light brown. Dorsum of abdomen with white pigment spots as in figure. Venter gray. Posterior eyes 0.5 diameters of anterior medians. Anterior laterals 0.4 diameters of anterior median eyes. Anterior median eyes 0.6 1980] Levi — Male of Echinotheridon 179 diameters apart, almost touching laterals. Posterior median eyes their diameter apart, their diameter from laterals. The height of the clypeus is slightly more than 2 diameters of anterior median eyes. The chelicerae are small and weak. Their length equals the height of the clypeus. The sternum is convex; the coxae are not modified. Total length, 1.22 mm. Carapace, 0.59 mm long, 0.57 mm wide. First femur, 0.81 mm; patella and tibia, 0.80 mm; metatarsus, 0.65 mm; tarsus, 0.45 mm. Second patella and tibia, 0.62 mm; third, 0.41 mm; fourth, 0.61 mm. Record. Brazil. Mato Grosso: Sinop [12° 31' S: 55° 37' W], October 1975, S (M. Alvarenga, AMNH). Literature Cited Branch, J. H. 1942. A spider which amputates one of its palpi. Bull. South. California Acad. Sci., 41: 139-140. Levi, H. W. 1955. The spider genera Chrysso and Tidarren in America (Araneae: Theri- diidae). J. New York Ent. Soc., 58: 59-81. 1963. American spiders of the genus Achaearanea and the new genus Echino- theridion (Araneae, Theridiidae). Bull. Mus. Comp. Zool., 129(3): 187-240. NEW SPECIES OF CONIOPTERYGIDAE (NEUROPTERA) FROM NORTH AMERICA 1 By Victor Johnson 2 Introduction Six new species of Coniopterygidae are herein described from North America. The descriptions are based primarily on male genitalia, but other characters are given where they appeared to be diagnostic. Specimens in this study were collected by the author (Coniopteryx delta and Semidalis tricornis) or borrowed from the following collections: Arizona State University (ARIZ), Illinois Natural History Survey (INHS), Pennsylvania State University (PSU) and Utah State University (UTAH). All specimens were examined in glycerine with a dissection microscope and drawings were made freehand with a counting grid in one ocular. Coniopteryx delta new species Type: Holotype male; Mexico; USNM. Head: Brown, eyes dark. Frons and palpi normal. Antennae greyish brown, 24-26 segmented. Scape and pedicel about as long as broad in males and one half times as long as broad in females. No scale-like hairs on flagellar segments (Fig. IF). Regular hairs about as long as segment is broad, arranged in two regular rows on flagellar segments. Each segment with a slightly curved seta, longer than segment is broad. Thorax: Brown with dark brown shoulder spots. Membrane of wings greyish brown. Length of fore wing 2.1-2.6 mm, hind wing 1.7-2.1 mm. Male genitalia (Fig. 1A-E): Hypandrium in lateral view about as high as broad. Apodeme along anterior margin complete. Processus terminales large, truncate, widely separated to form a very wide V- 'This paper (No. 80-7-161) is published with the permission of the Director of the Kentucky Agricultural Experiment Station and is based on research performed in partial fulfillment of the requirements for the Ph.D. degree in Entomology. 2 Former student in Department of Entomology, University of Kentucky, Lexington, Kentucky 40546. Present address: USDA, Box 182729, Erlanger, Kentucky 41018. Manuscript received by the editor January 26, 1981. 181 Psyche [Vol. 87 182 .Fig. 1. Coniopteryx delta. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Hypandrium, ventral view. D. Paramere, lateral view. E. Male internal genitalia, ventral view. F. Male antennal segments 8-10. shaped median apical incision. Processus laterales prominent. Gonarcus well developed. Hypandrium with an inner, distally bifurcate plate attached to median apical incision. Stylus forked, outer branch bent slightly forward. Inner branch forming an arch below parameres and connected with processus ventrales of para- meres. Processus apicalis in lateral view acute and bent slightly forward with a longer acute ventral process. In caudal view, parameres broadly triangular, produced laterally. Penis apparently consisting of one sclerotized rod. Female genitalia: Gonapophyses laterales sclerotized, separate. Holotype male: Mexico: Veracruz, Catemaco, 111-14-1976, V. 1980] Johnson — New Coniopterygidae 183 Johnson, sweeping. Paratype: 1 female, same data as holotype. Both specimens deposited in USNM. Notes: This species belongs to the C. westwoodi group. Besides genitalic differences, this species can be separated from related species by the lack of scale-like setae on the flagellar segments, lack of a hook on the frons and the presence of an inner, distally furcate, transverse plate on the hypandrium. No other North American species has this combination of characters. Coniopteryx dorsicornis new species Coniopteryx simplicior Meinander (in part), 1972:261. Type: Holotype male; Florida; PSU. Head: Brown. Frons and palpi normal. Antennae (Fig. 2F) yellowish brown, 29-30 segmented (left antenna with 29 segments with first flagellar segment partially subdivided, right antenna with 30 segments). Scale-like hairs in several whorls on apices of flagellar segments. Basal flagellar segments rounded, about as long as broad. Ordinary hairs on flagellar segments in two whorls, about as long as width of segment. Each segment with a slightly curved seta, slightly longer than width of segment. Thorax: Brown with dark brown shoulder spots. Membrane of wing yellowish-brown. Length of fore wing 3.0 mm, hind wing 2.6 mm. Male genitalia (Fig. 2A-E): Hypandrium in lateral view higher than broad, skewed dorso-caudally. Apodeme along anterior margin ventrally interrupted, dorsally continued along dorso-lateral margin of hypandrium for a short distance. Processus terminales acute, median apical incision V-shaped. Processus laterales not prominent. Gonarcus well developed. Hypandrium with a large inner distally bifurcate plate attached to median apical incision. Stylus forked, outer branch bent forewards. Processus ventrales of parameres connected. Processus apicalis long, diverging dorsally, sub-equal to a long ventral process. Penis consisting of two rods, apparently fused caudally. Holotype male: Florida: Highlands Co., Archbold Biological Station, III-30-IV-5-1967, S. W. Frost. Holotype deposited in museum of Pennsylvania State University. Notes: This species belong to the C. westwoodi group. This specimen was one of a lot identified as C. simplicior Meinander by 184 Psyche [Vol. 87 Fig. 2. Coniopteryx dorsicornis. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Hypandrium, ventral view. D. Paramere, lateral view. E. Internal male genitalia, ventral view. F. Male antennal segments 8-10. Meinander and according to the International Rules of Zoological Nomenclature is a paratype of C. simplicior. C. dorsicornis can be easily separated from C. simplicior by the long processus apicalis, the ventrally interrupted apodeme along the anterior margin of the hypandrium, the lack of a longitudinal apodeme connected to bottom of median apical incision and by the more developed gonarcus. 1980] Johnson — New Coniopterygidae 185 Coniopteryx forcipata new species Type: Holotype male; Arizona; USNM. Head: Yellow. Frons and palpi normal. Antennae (Fig. 3F) brown, 22-25 segmented. Flagellar segments wider than long, especially proximal ones which are much wider than long, disc-like. Median and distal flagellar segments gradually becoming longer until almost as long as wide. Ordinary hairs in two irregular rows. Seta present and scale-like hairs present on apical ends. Thorax: Yellowish with brown shoulder spots. Wing membrane greyish. Length of fore wing 2.0-3.2 mm, hind wing 1.7-2.6 mm. Male genitalia (Fig. 3 A-E): Hypandrium in lateral view about as Fig. 3. Coniopteryx forcipata. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Hypandrium, ventral view. D. Paramere, lateral view. E. Male internal genitalia, ventral view. F. Male antennal segments 8-10. 186 Psyche [Vol. 87 high as broad. Apodeme along anterior margin ventrally complete. Median apical incision deep, narrow and parallel-sided. Processus terminales prominent, rounded. Processus laterales prominent, digit-like. Hypandrium with a small, inner, distally bifurcate, transverse plate on median apical incision. Gonarcus rather small. Styli forked, inner branches extending forward, not connected to each other. Processus apicalis acute with a very long ventral process. Ventral process at least twice length of processus apicalis. In caudal view, parameres appearing caliper-like with long narrow ventral process curving slightly medially at apical ends. Penis formed of two small rods. Holotype male: Arizona: Cochise Stronghold, Dragoon Mts., VI- 20-24-1970, R. J. Shaw, blacklight trap. Paratypes: Arizona: Pinal Co., Superior, 1 male, V-28-1946, B. W. Benson, at light; 1 male, V-17-24-1946, B. W. Benson, at light; 2 males, IV-21-1949, B. W. Benson, at light; 1 male, H. K. Gloyd, at light; Cochise Stronghold, Dragoon Mts., 13 males, R. J. Shaw, blacklight trap, following dates: 2 males VIII-12-15-1969; 1 male, V- 12-17-1970; 1 male, VI-20-24-1970; 4 males, VI-27-29-1970; 1 male, VII- 15-18-1970; 2 males, VII-24-27-1970; 1 male, IX-4-9-1970; 1 male, IX-21-28-1970. Deposited in ARIZ, INHS, USNM and collection of the author. Notes: This species belongs to the C. westwoodi group. C. forcipata is similar to C. dorsicornis but differs in the shape of the hypandrium and parameres. In addition, the inner branches of the styli in C. dorsicornis are connected, forming an arch below the parameres; while in C./orci/>atatheinnerbranchesarenotconnected. Coniopteryx meinanderi new species Type: Holotype male; Arizona; USNM. Head: Brown, frons and palpi normal. Antennae (Fig. 4F) dark brown, 34-27 segmented. Flagellar segments about as long as broad to about one and one half times as long as broad. Ordinary hairs in two irregular whorls. Plate-like hairs absent. Seta present. Thorax: Brown with dark brown shoulder spots. Wings with membrane brown. Length of fore wing 2.2-3.4 mm, hind wing 2.2-3.0 mm. Male genitalia (Fig. 4A-E): Hypandrium in lateral view sub- triangular, much wider ventrally than dorsally. Apodeme along 1980] Johnson — New Coniopterygidae 187 Fig. 4. Coniopteryx meinanderi. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Hypandrium, ventral view. D. Paramere, lateral view. E. Male internal genitalia, ventral view. F. Male antennal segments 8-10. anterior margin ventrally complete. Processus terminates short, acute. Processus laterales absent. Median apical incision slit-like, margins heavily sclerotized. Hypandrium with an inner, triangular extension (in lateral view) from median apical incision. Gonarcus small, terminating in a tooth. Styli originating about midway on gonarcus, band-like, forming an,arch below parameres. Parameres elbowed at processus ventrales. Processus apicalis bifurcate, inner branch short, straight; outer branch longer, curved medially. Penis consisting of two rods, apical halves of which are curved downward at almost right angle. In caudal view, penis looks pincer-like. 188 Psyche [Vol. 87 Female genitalia: Gonapophyses laterales fused, forming a heavily sclerotized transverse plate. Holotype male: Arizona: Cochise Stronghold, Dragoon Mts., R. J. Shaw, blacklight trap. Paratypes: Arizona: Pinal Co., Superior, 1 male, V-2-8-1946, B. W. Benson, light trap; 1 male, V-17- 24-1949, B. W. Benson, light trap; 5 males, VII-16-VIII-5-1948, H. K. Gloyd, at light; Doscabezas, 1 male, VI1-24-26-1970, S. Kozloski, U.V.; Cochise Stronghold, Dragoon Mts., R. J. Shaw, blacklight trap, 650 males 500 females at various dates from VIII-14-1969 to X- 7-1970. Deposited in ARIZ, INHS, USNM and collection of the author. Notes: This species belongs to the C. diversicornis group. C. meinanderi is similar to C. texana Meinander and C. diversicornis Meinander but differs in the shape of the caudal incision of the hypandrium. The caudal incision is narrow and slit-like in C. meinanderi and rounded in the other two species. This species is dedicated to Dr. Martin Meinander. Coniopteryx quadricephala new species Type: Holotype male; Utah; USNM. Head (Fig. 5A-B): Brown. Frons unsclerotized except for a median vertical band with four large stiff setae at the ventral end. Below it a large curved hook. Hook laterally expanded, somewhat flattened until just before tip where it becomes more rounded, narrower. Hook almost forms a circle, with the tip close to the base. Inner curve of hook with many large, stiff setae; a large patch at base, one or two about one third of length of hook from base, and a small patch about one third the length of hook from the end. All setae converge in center of hook. Vertex of head produced anteriorly to form a large shelf-like area, flat on top and square when viewed dorsally. Antennae (Fig. 5A-B and Fig. 6F) brown, 24-26 segmented. Scape and pedicel longer than broad. First flagellar segment partially subdivided with two stiff setae on dorsal side close to proximal end. Most distal of these two setae with terminal one third curved proximally. Remaining flagellar segments with a smaller, stiff, straight seta; one distally slightly curved setae present. Flagellar segments with regular hairs in two regular whorls and with scale-like hairs at apices. Maxillary palpi with fourth segment greatly enlarged, hatchet-shaped with a small area covered with short sensory hairs. 1980] Johnson — New Coniopterygidae 189 Fig. 5. Coniopteryx quadricephala. A. Male head, lateral view. B. Male head, dorsal view. Remaining segments of maxillary and labial palpi normal. Thorax: Brown with dark brown shoulder spots. Membrane of wings light greyish brown. Length of fore wing 3.4-4.0 mm, hind wing 2.6-3.0 mm. Male genitalia (Fig. 6A-E): Hypandrium in lateral view about as high as broad. Apodeme along anterior margin ventrally complete, dorsally extending for a short distance along hypandrium margin. Median apical incision fairly shallow, V-shaped. Processus terminales acute. Processus laterales prominent. Hypandrium with an inner, distally bifurcate plate attached to median apical incision. Gonarcus broad. Styli forked at base. Inner branches membranous, fused together below parameres, attached to processus ventrales, outer branches short. Processus apicalis rounded in caudal view with a somewhat longer ventral process, truncate and parallel sided in caudal view. Penis formed of two small rods. Holotype Male: UTAH: Cache Co., Green Canyon, VII-25-30- 1968, W. J. Hanson, malaise trap. Paratypes: Cache Co., Green Canyon, 2 males, VII-25-30-1968, W. J. Hanson, malaise trap; 1 male, VII-27-VIII-2-1968, W. J. Hanson, malaise trap; 1 male, VI-28- 1969, malaise trap; 2 males, VII-4-1969, W. J. Hanson, malaise trap. 190 Psyche [Vol. 87 Fig. 6. Coniopteryx quadricephala. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Hypandrium, ventral view. D. Paramere, lateral view. E. Male internal genitalia, ventral view. F. Male antennal segments 8-10. Deposited in USNM, UTAH and collection of the author. Notes: This species belongs to the C. westwoodi group. C. quadricephala can be separated from all related species by the shape of the head. No related species has the vertex of the head produced as previously described and figured. Semidalis tricornis new species Type: Holotype male; Arizona; USNM. Head: Light reddish tan. Antennae yellowish grey, 29-33 seg- 19B0] Johnson — New Coniopterygidae 191 merited. Flagellar segments slightly longer than broad. Thorax: Light yellowish grey with greyish brown shoulder spots. Membrane of wings light fuscous. Length of fore wing 3.0-3.5 mm, hind wing 2.4-3.8 mm. Male genitalia (Fig. 7): Outer process of ectoprocts rather short, Fig. 7. Semidalis tricornis. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Male internal genitalia. D. Paramere, lateral view. E. Uncim, lateral view. F. Uncini, caudal view. stout. Process at inner angle of ectoprocts small, triangular. Hypan- drium dorsally terminating in a long spine, slightly curved ventrad. Parameres apically swollen with a deep dorsal incision formed by body of paramere and dorsally directed spine terminally. A large dorsally directed spine in middle, curving medially and slightly anteriorly. Anterior to large spine a small prpcess originating on lateral side of paramere and projecting forward. Uncini fused into a transverse plate, in caudal view with broad dorsal and ventral incisions. 192 Psyche [Vol. 87 Holotype male: Arizona: Cochise Stronghold, Dragoon Mts., R. J. Shaw, blacklight trap; Paratypes: Cochise Stronghold, 1 male, IX-11-15-1969; 1 male, VI-27-29-1970; 1 male, VII-24-27-1970; Mexico; oaxaca; 0.5 mi. S. of Llano Verde, 1 male, III-21-1976, V. Johnson. Deposited in USNM and the collection of the author. Notes: This species belongs to the S. vicina group. Genitalically, S. tricornis is similar to S. arnaudi Meinander, but differs in the shape of the parameres. The terminal spine is longer in S. tricornis and the dorsal incision is much deeper and narrower. In addition, the central spine of S. tricornis is directed dorsally rather than forwards and is closer to the caudal end. The Mexican specimen is much larger than the Arizona specimens. The Arizona specimens have wing spans of 3.0-3.2 mm fore wing, 2.4-2.6 mm hind wing, and have 29-30 antennal segments (the holotype has right antennae with 29 segments and left with 30); the Mexican specimen has wing span of 4.5 mm fore wing, 3.8 mm hind wing and has 33 antennal segments. Reference Cited Meinander, M. 1972 A revision of the family Coniopterygidae (Planipennia). Acta Zool. Fennica 136 : 1-357. DESCRIPTION OF A NEW WOLF SPIDER IN THE GENUS PIRATA (ARANEAE: LYCOSIDAE)* By C. D. Dondale and J. H. Redner Biosystematics Research Institute, Agriculture Canada, Ottawa, Ontario K1A 0C6 Introduction The genus Pirata Sundevall consists of rather small, active wolf spiders that frequent the vegetation of bogs, swamps, margins of ponds and streams, and, more rarely, salt marshes. In a recent revision, Wallace and Exline (1978) divided the North American species of Pirata into groups based on genitalia, body size, leg setation, and color pattern on the carapace. Their insularis group contained two species, namely, P. insularis Emerton, which ranges from the western part of the Northwest Territories to New Brunswick and southward to Arizona and Florida, and P. cantralli Wallace and Exline, which was known only from Michigan and Ontario. Subse¬ quent collections of cantralli indicate that it ranges as widely in Canada as insularis, though southward only to Michigan. Wallace and Exline (1978) noted the presence of a prominent, basally-directed tooth on the median apophysis of the male palpus of both P. insularis and P. cantralli. This tooth is absent in representa¬ tives of other North American groups of Pirata, but is present in males of certain Palaearctic species of the genus such as P. piccolo Dahl (Holm, 1947, Fig. 9; Fuhn and Niculescu-Burlacu, 1971, Fig. 103c), P. japonicus Tanaka (Tanaka, 1974, Fig. 14), P. procurvus (Bosenberg and Strand) (Tanaka, 1974, Fig. 31; Song et al., 1978, Fig. 9D), and P. praedatoria Schenkel (Song et al., 1978, Fig. 8E). This suggests that the insularis group is a widespread component of the world genus Pirata. The purpose of this paper is to describe a new species of Pirata, the male of which also has a dorsal tooth on the median apophysis and which we therefore assign to the insularis group. * Manuscript received by the editor January 23, 1981. 193 194 Psyche [Vol. 87 Pirata canadensis, n.sp. Figures 1-8 Types: Holotype: male, Whirlpool Lake, Riding Mountain Na¬ tional Park (R.M.N.P.), Manitoba (August 27, 1979; J. H. and M. Redner). Paratypes: 4 females, same data as holotype; 1 male, 2 females, same data except August 20, 21; 1 female, Whirlpool River, R.M.N.P., Manitoba (June 22, 1979; S. J. Miller); 7 males and 7 females, Swanson Spring, R.M.N.P., Manitoba (June 20-July 18, 1979; D. B. Lyons); 1 male, Wasagaming, R.M.N.P., Manitoba (August 29, 1979; J. H. and M. Redner); 1 male, Agassiz Forest Reserve, Manitoba (July 1, 1964); 2 males, 1 female, Poltimore, Papineau Co., Quebec (May 18-August 3, 1979; J. H. Redner and C. D. Dondale); 3 males, 2 females, Kouchibouguac National Park, Kent Co., New Brunswick (June 8-August 16, 1977; G. A. Calder- wood). The holotype and paratypes are deposited in the Canadian National Collection of Insects and Arachnids, Ottawa. Etymology: The specific name is based on the name of the country in which the type-series was collected. Diagnosis: Individuals of P. canadensis differ from those of the other North American species in the insularis group by being smaller (range of carapace length and width, respectively, 1.52-1.90 and 1.01-1.28 mm, contrasted with 2.00-3.45, 1.32-2.55 mm for P. insularis and 2.17-2.71, 1.50-2.06 for P. cantralli). The carapace usually lacks the dark lateral rim found in individuals of the other species, and the venter of the abdomen often has three dark coalescent longitudinal bands, or a single broad dark area, rather than slender separate bands. The distitarsus of leg I in males is also somewhat curved rather than straight. Specimens of P. canadensis do not key to either insularis or cantralli in Wallace and Exline’s (1978) key owing to the frequent lack of a dark lateral rim on the carapace and to the small body size. Male: Total length approximately 3.00 mm. Carapace 1.71+ 0.07 mm long, 1.13+ 0.05 mm wide (15 specimens measured). Carapace shiny, somewhat irridescent; brown yellow or yellow orange, with margins sometimes somewhat darkened; usually with broad mar¬ ginal pale area, paired dark longitudinal bands, and tuning-fork mark anterior to dorsal groove; posterior margin somewhat concave; lateral margins almost smoothly convex, strongly narrowed at level of coxae I and II; height approximately uniform from dorsal groove 1980] Dondale & Redner — Genus Pirata 195 Figs. 1-12. Structures of Pirata spp. 1-8. P. canadensis n.sp. 1, 2. Apical division of left male genital bulb. 1. Ventral view. 2. Retrolateral view. 3. Male palpus, ventral view. 4. Body of female, dorsal view. 5. Epigynum, ventral view. 6. Epigy- num, dorsal view, cleared. 7, 8. Median apophysis. 7. Ventral view. 8. Retrolateral view. 9, 10. Median apophysis of P. cantralli Wallace and Exline. 9. Ventral view. 10. Retrolateral view. 11, 12. Median apophysis of P. insularis Emerton. 11. Ventral view. 12. Retrolateral view, e, embolus, ma, median apophysis, spt, spermatheca. steg, subtegulum. 196 Psyche [Vol. 87 to posterior row of eyes; front nearly vertical; setae short, dark, suberect, rather sparse. Anterior row of eyes shorter than middle row, somewhat procurved, approximately uniform in spacing, with anterior median eyes somewhat larger than anterior laterals. Ster¬ num brown yellow, sometimes suffused with black or with indistinct pale median band and pale submarginal spots. Chelicerae brown yellow; promargin of fang furrow with 2 or 3 teeth and retromargin with 3 teeth. Legs pale brown yellow, with patella and tibia I somewhat darker, not annulated, somewhat irridescent; scopula sparse; femur I with 3 dorsal macrosetae, 1 prolateral, 0 retrolaterals; tibia I with 0 dorsal macrosetae (though 2 bristles present), 1 or 2 prolaterals, 0 retrolaterals, 3 pairs of ventrals; basitarsus I with 0 dorsal macrosetae, 1 to 3 prolaterals, 1 retrolateral, 2 pairs of ventrals plus 1 unpaired at tip; distitarsus I with slight curvature; trochanter with deep ventral notch at tip. Abdomen ovoid, brown yellow, with indistinct heart mark and dark reticulated pattern, occasionally lacking pattern, with cluster of erect curved setae at anterior end; venter pale brown yellow, often with a median and 2 lateral dark longitudinal bands coalescing or forming a median patch. Tibia of palpus nearly twice as long as wide. Subtegulum (steg) large, prominent, occupying approximately one-third length of genital bulb (Fig. 3); seminal duct sinuous, nearly transverse; median apophysis (ma) angular at base, long and curved at tip, with slender dorsal tooth (Figs. 3, 7, 8); embolus (e) short, slender, arising close to terminal apophysis on prolateral margin of genital bulb, held in groove formed by folded margin of terminal apophysis (Fig. 2); terminal apophysis with two minute processes (Figs. 1, 2). Female: Total length approximately 3.75 mm. Carapace 1.78+ 0.09 mm long, 1.19+ 0.06 mm wide (17 specimens measured). General structure and color (Fig. 4) essentially as in male but body sometimes lacking pattern; anterior median eyes sometimes equal to anterior laterals in size; patella and tibia I not darker than other segments; tibia I with distal pair of ventral macrosetae often missing; basitarsus I lacking ventral unpaired macroseta tip, and distitarsus I not curved. Epigynum with plate somewhat longer than broad, rather convex, setaceous, lacking processes at posterior margin (Fig. 5). Copulatory tubes broad, each with rounded prominence postero- laterally; spermathecae (spt) longer than broad, extending antero- laterad, with minute nodules at tip (Fig. 6). Material Examined: Only the type-series was examined. 1980] Dondale & Redner — Genus Pirata 197 Range: Manitoba to New Brunswick. Natural History: All of the available specimens were collected in pitfall traps or by sifters in sphagnum bogs. The paratypes from Poltimore, Quebec were collected in a small bog with specimens of P. insularis and P. cantralli. References Cited Fuhn, I. E. and F. Niculescu-Burlacu. 1971. Fauna Republicii Socialiste Romania, Arachnida, Volumul V, Fascicula 3, Fam. Lycosidae. Academia Republicii Socialiste Romania, Bucuresti. 256 pp. Holm, A. 1947. Svensk spindelfauna. 3. Egentliga spindlar. Araneae. Fam. 8-10, Oxy- opidae, Lycosidae och Pisauridae. Entomologiska Foreningen, Stock¬ holm. 48 pp. Song, D. X„ D. W. Shang, R. M. Wang, C. F. Cheng, and S. X. Cheng. 1978. On the wolf spiders from farm fields in Chekiang Province. Zool. Mag. 2:1-5 (Chinese). Tanaka, H. 1974. Japanese wolf spiders of the genus Pirata, with descriptions of five new species (Araneae:Lycosidae). Acta Arachnol. 26: 22-45. Wallace, H. K.. and H. Exline 1978. Spiders of the genus Pirata in North America, Central America and the West Indies (Araneae:Lycosidae). J. Arachnol. 5:1-112. STRIDULATION BY WORKERS OF THE ANT, LEPTOTHORAX MUSCORUM (NYLANDER) (HYMENOPTERA: FORMICIDAE).* By R. J- Stuart and P. D. Bell Department of Zoology, Erindale College, University of Toronto, Mississauga, Ontario L5L 1C6 Canada Introduction Many ponerine, myrmicine and pseudomyrmecine ants possess an abdominal stridulatory apparatus (Markl, 1973) of the type first described by Landois in 1874. The file (pars stridens) consists of a series of fine, regular, transverse striations, and is located medially on the anterior portion of the fourth abdominal tergite. The posterior edge of the preceding tergite serves as the scraper (plec¬ trum), and stridulation is effected by dorso-ventral movements of the gaster which telescope the pars stridens beneath the plectrum. Exceptions to this typical arrangement have been documented by Sharp (1893), Marcus and Marcus (1951) and Taylor (1978). Ant stridulation produces a substrate-borne vibratory signal, which is accompanied by an acoustic component in larger species (Dumortier, 1963). However, ants are not known to hear airborne sound, and it is the substrate-borne component of this signal which is thought to function in communication (Haskins and Enzmann, 1938; Markl, 1968, 1970). In Ana cephalotes, three groups of campaniform sensilla at the joint between the trochanter and femur are apparently responsible for vibration reception (Markl, 1970). Ant stridulation occurs in a variety of contexts and, although various effects have been attributed to this signal (see review in Dumortier, 1963), few have been demonstrated (Markl, 1965, 1967; Markl et al„ 1977; Markl and Holldobler, 1978). Furthermore, most previous authors have investigated stridulation in a particular context, in one or a few species, and there is little appreciation of how species specific some of the documented contexts may be, or in * Manuscript received by the editor November 28, 1980. 199 200 Psyche [Vol. 87 how many contexts single species may utilize stridulation. One exception is the work of Zhantiev and Sulkanov (1977), who found that certain Myrmica species would stridulate during immobiliza¬ tion, trophallaxis, fighting and eating insects. Nevertheless, the stridulatory signal itself is relatively simplistic and, according to Markl and Holldobler (1978), is probably not capable of containing more than one type of message. They have suggested that ant stridulation is a form of modulatory communication, and that the signal does not release any specific response, but merely modulates the responses of ants to other stimuli. In their work with Novomessor, Markl and Holldobler (1978) found that a stridulating worker did not transmit any detectable signal to the substrate through its legs. Apparently, other portions of the ant’s body had to be in contact with the substrate for effective transmission to occur. This discovery, if generally applicable to other ants, could be an important restriction on communication by stridulation. Leptothorax muscorum (Nylander) is a small (length = 2.1-3.8 mm), common, circumboreal myrmicine ant (Brown, 1955; Ber nard, 1968). In North America, L. muscorum colonies normally consist of one or more queens, and less than 100 workers, and can be found nesting in rotting wood, under rocks and in other similar cavities (Stuart, 1978). Haskins and Enzmann (1938) reported that L. acervorum canadensis var. yankee (= L. muscorum, Brown, 1955) workers stridulated when licking their larvae. Stridulation has also been noted among other Leptothoracine ants (Adlerz, 1896; Wheeler, 1903; Wilson and Fagan, 1974). This study is a preliminary investigation of stridulation in L. muscorum workers. The purpose is to observe the stridulatory apparatus of L. muscorum workers; to monitor the substrate-borne and airborne components of their stridulatory signal; to discover if the signal can be transmitted through the ant’s legs; and to enumerate the contexts in which L. muscorum workers stridulate both inside and outside their nests. Methods and Materials L. muscorum colonies were collected from rotting wood near Rouyn, Quebec, and maintained in the laboratory using techniques described by Alloway (1980). The ants were fed three times a week 1980] Stuart & Bell — Leptothorax 201 Fig. 1. Scaning electron micrographs of the stridulatory apparatus of an L. mus- corum worker: a, general view; PP, post-petiole, PS, pars stridens, G, gaster. b, detail in central region of pars stridens. 202 Psyche [Vol. 87 on a liquefied diet of the type described by Bhatkar and Whitcomb (1970), and water was available ad libitum in their foraging dishes by way of bottles, stoppered with cotton. Substrate vibrations were detected using a Bruel and Kjaer4344 accelerometer, and amplified by a B & K 2304 impulse sound level meter on linear response. The vibrations were recorded on a Uher 4000 Report IC tape recorder. Oscillograms were produced on a Tektronix 455 oscilloscope, and recorded with a Nihon Koden continuous photographic recorder. Attempts to record the airborne component of the stridulatory signal utilized a B & K4133, !/ 2 "(1.25 cm) microphone in conjunction with the above mentioned sound level meter and tape recorder. The stridulatory apparatus was photographed with a Cambridge S 180 scanning electron micro¬ scope. Ants normally stridulate when they are restrained (Markl et al., 1977) and, therefore, in our initial attempts to record the stridula¬ tory vibrations produced by a L. muscorum worker, we glued the ventral portion of its head to the base of the accelerometer with contact rubber cement. To test for the transmission of stridulatory Fig. 2. Same as figure 1: leading edge of the pars stridens, after removing the post-petiole, showing the interface between the fine structure of the file and the sculpturing of the adjoining region. 1980] Stuart & Bell — Leptothorax 203 vibrations through the legs, a worker’s antenna was clamped in forceps secured above the accelerometer, such that only the ant’s legs rested upon the base. Attempts to monitor the airborne component of stridulation were made using the initial procedure, and by holding the microphone to within 1 cm of the ant. All recordings were conducted in a sound attenuating room which floats on a concrete, vibration-dampening pad. During recording sessions, the ants were observed through a dissecting microscope, and were occasionally stimulated with a camel’s hair brush, or with air blown through a tygon hose (diam = 0.5 cm). Stridulatory contexts were determined visually through observation of laboratory colonies through a dissecting microscope, and under varying conditions as described in the results. Voucher specimens have been deposited in the Museum of Comparative Zoology, Harvard University. Results 1. Structure The stridulatory apparatus of a L. muscorum worker occurs on the dorsal surface of the third and fourth abdominal tergites. The pars stridens is located in the mid-dorsal region of the anterior portion of the first gastric segment, and the plectrum apparently consists of the trailing edge of the post-petiole (Figs. 1 and 2). Other portions of the worker’s body were examined with the electron microscope in an attempt to locate other possible stridulatory structures, but none were found. 2. Signal Workers glued to the accelerometer surface responded by persis¬ tently pulling and struggling to free themselves. This activity was accompanied on an intermittent basis by very characteristic and regular dorsoventral movements of the gaster, which occurred in short bursts and in more prolonged sequences. During these movements a distinct vibratory signal was detected by the accel¬ erometer (Fig. 3). The highly characteristic stridulatory movements of this species make visual observation through a dissecting micro¬ scope a reliable means of determining the occurrence of stridulation. The acceleration of the vibratory signal was measured as 1.4 X 10 m/sec ? RMS (= 1.95 X 10~ 4 m/sec 2 p-p). However, no further 204 Psyche [Vol. 87 analysis of the signal was attempted due to the high signal-to-noise ratio. We were unable to detect any airborne component to this stridulatory vibration. Workers restrained by having an antenna clamped in forceps responded in the same manner as those re¬ strained with glue. Similarly, when a worker was engaged in apparent stridulatory movements, a vibratory signal of the type described above was recorded from the substrate. Thus, the vibra¬ tory signal produced by a L. muscorum worker is readily trans¬ mitted to the substrate through its legs. ** lip. . . ■ mu ' .. m u 0.25 sec. Fig. 3. Sonogram of the substrate-borne vibratory signal produced by a stridulat- ing L. muscorum worker. 3. Context A. Restrained L. muscorum workers will stridulate when they are restrained. Such restraint can be imposed by glue or forceps, and occasionally occurred in laboratory colonies when an ant became trapped under the lid of its nest or foraging dish. It has been suggested that similar situations might arise in nature as the result of nest cave-ins, or fighting (Markl, 1965; Spangler, 1967). B. Fighting L. muscorum workers are often aggressive to alien conspecifics, and will bite, pull and dismember such aliens during prolonged fights (Stuart, 1978). Stridulation is characteristic of these fights and is displayed not only by workers which are being held or pinioned by their opponents, but also by those workers which are holding or pinioning their opponents. Stridulation in the former situation may be analogous to that displayed by restrained ants, but in the latter situation occurs in quite a different behavioral context. Adult alien conspecifics are dismembered and killed but are not eaten (Stuart, 1978), and therefore this context differs from feeding. 1980] Stuart & Bell — Leptothorax 205 C. Feeding L. muscorum workers stridulate intermittently as they bite, pull and tear apart solid food such as insect fragments, both outside and inside their nests. Stridulation is seen among groups of workers biting on a common food item, and is also displayed by workers biting on tissue individually. In culture, workers do not normally stridulate when consuming liquids. However, if a colony has been deprived of food and water for 5-7 days, workers will frequently stridulate when consuming honey, Bhatkar and Whitcomb diet, or even water. D. Trophallaxis When foragers return to the nest after having consumed liquid food, they engage in oral trophallaxis with adult members of their colony. Recipients hold their mandibles closed during trophallaxis and frequently stridulate; while donors hold their mandibles open and occasionally stridulate. In one study, 20 bouts of trophallaxis, lasting longer than 10 sec, were observed in each of three colonies. Thirty-eight bouts had a single recipient, eleven had two, seven had three, three had four, and one had five. Forty-seven of the 98 recipients stridulated at least briefly during trophallaxis; while only 4 donors did so. At least one recipient stridulated in each of 38 bouts, and both donor and at least one recipient stridulated during two bouts. Stridulation occurred in short bursts and prolonged sequences, and appeared to occur more often near the end of bouts, or when additional workers joined groups already engaged in trophallaxis. L. muscorum workers also stridulate during certain bouts of oral trophallaxis with larvae. During the feeding session described above, five incidents of trophallaxis between workers and larvae were recorded. They lasted 5, 6, 10, 20, and 25 sec respectively. In each case the worker stridulated for nearly the entire bout. How¬ ever, on other occasions workers have been observed engaging in apparently similar bouts of trophallaxis, but with no stridulation whatsoever. In either case, it is unknown whether the workers involved were actually giving liquids to the larvae, or receiving them. E. Allogrooming In laboratory colonies, L. muscorum workers often lick the body surfaces of their nest-mates. This grooming is directed to adults and 206 Psyche [Vol. 87 to brood, and under normal conditions, is not accompanied by stridulation. However, if colonies are deprived of food and water for 5-7 days, workers grooming other adults and larvae will frequently stridulate. It is possible that secretions are being obtained from the body surfaces, and that under such stressful conditions provide sufficient stimuli to induce stridulation. F. Brood Manipulation In attempting to manipulate or move larvae, workers occasionally encounter a larva which has become securely stuck to the floor of the nest. Workers respond to this resistence by pulling on the larvae, and frequently stridulate as they do so. In this context stridulation is associated with pulling, as it is when fighting or feeding. Neverthe¬ less, all of these situations represent different behavioral contexts, and have therefore been considered separately. Discussion L. muscorum workers possess a well defined stridulatory ap¬ paratus, similar to that of certain other ponerine, myrmicine and pseudomyrmecine ants (Markl, 1973). When restrained, L. muscor¬ um workers display characteristic dorsoventral movements of the gaster which are associated with, and apparently induce, weak vibrations in the substrate, but no detectable airborne sound. This vibratory signal is transmitted to the substrate through the ant’s legs. Similar stridulatory movements are observed when workers are fighting, dissecting insects, engaging in trophallaxis with adults and larvae, and when attempting to move larvae that adhere to the substrate. Furthermore, in food and water deprived colonies, stridulation occurs when workers groom other adults or larvae, or consume liquid food or water. Although the function of stridulation during the above contexts remains unknown, the intermittent nature of this behavior during all of these activities indicates that it is not an essential component of any of them. Markl (1970) found that small workers of Atta cepholotes were more sensitive to stridulatory vibration than large workers. The minimum threshold for vibration reception in these small workers was 2.5 cm/ sec 2 (p-p) (sic) acceleration. In this study, the accelera¬ tion of the L. muscorum stridulatory vibrations was 1.95 X 10” 6 cm/sec 2 (p-p). The small size of L. muscorum workers probably 1980] Stuart & Bell — Leptothorax 207 accounts for the weak stridulatory signal, and for the apparent absence of any airborne signal (see discussion in Dumortier, 1963). Markl and Holldobler (1978) reported that Novomessor workers did not transmit any detectable vibratory signal to the substrate through their legs. We found this not to be true with L. muscorum workers. However, the necessity of having some part of the ant’s body, other than its legs, in contact with the substrate, or some other object or individual, to facilitate transmission of the signal, could be an important communicative constraint in some species. Wilson and Fagen (1974) included stridulation in their ethogram of L. curvispinosus workers, and apparently observed it as a mutually exclusive behavior pattern. In the present study, L. muscorum workers only stridulated in association with some other behavior. However, in L. curvispinosus colonies cultured under similar conditions we have observed workers exhibiting such mutu¬ ally exclusive stridulation in apparent response to a mild disturb¬ ance, such as moving the culture dish across the stage of a dissecting microscope. In addition, L. curvispinosus workers will stndulate in many of the contexts outlined in this paper for L. muscorum, but only in this ‘mild alarm’ context is this behavior mutually exclusive. L. muscorum workers begin to run about their nests, even upon a slight disturbance, and we have never observed stridulation in a similar context for this species. Free-standing stridulation of this type underlines the potential importance of the transmission of a stridulatory signal through an ant’s legs to the substrate. Our behavioral observations of L. muscorum workers confirm and extend previous accounts of stridulation in Leptothoracine ants. Adlerz (1896) noted that workers stridulated during trophal- laxis, when feeding or licking their nest-mates, and when feeding their'larvae. Wheeler (1903) observed workers stridulating while feeding on insect fragments, and Haskins and Enzmann (1938) reported workers stridulating when licking their larvae. The occurrence of stridulation in such a wide variety of contexts within a single species, such as L. muscorum, argues against the possibility that this signal might release a specific response, and supports Markl and Holldobler’s (1978) suggestion that ant stridu¬ lation serves a modulatory function. The fact that stridulation is observed in additional contexts when colonies have been deprived of food and water, suggests that the motivational state of the ants may be a factor in stridulation. Zhantiev and Sulkanov (1977) 208 Psyche [Vol. 87 report variations in the stridulatory signal of Myrmica which they suggest could reflect the relative motivation of the signalling worker. If so, stridulation could constitute a finely graded signal which serves as a sensitive indicator of the relative motivational state of workers engaged in various social interactions with nest- mates. In this manner, stridulation would be an important contri¬ bution to the efficiency of these interactions and of the colony as a whole. Stridulation could simultaneously serve as an effective short- range recruitment signal or orientation cue, especially within the nest. Outside the nest, L. muscorum workers recruit nest-mates by tandem running to food (Moglich et al., 1974) and to fighting (Stuart, 1978). The occurrence of stridulation at the scene of either of these activities could serve to facilitate such chemical recruitment, as it has been shown to do for food recruitment in Novomessor (Markl and Holldobler, 1978). However, these suggested functions for stridulation in L. muscorum remain speculative, and the precise determination of the effects of this signal, in the various contexts described in this study, await further research. Acknowledgements We thank E. Lin and B. Moose of the Laboratory of Analytical Systematics in the Department of Zoology, University of Toronto, for their electron microscopy. We appreciate financial support from an Ontario Graduate Scholarship, a NSERC Postgraduate Scholar¬ ship, and N.R.C. (Canada) Grants #A0301 and #4946 to R.S., P.B., and Drs. T.M. Alloway and G.K. Morris respectively. Summary L. muscorum workers possess a stridulatory apparatus on the dorsal surface of the third and fourth abdominal tergites. Stridula¬ tion is readily induced by gluing the ventral portion of a worker’s head directly to the accelerometer. Under these conditions, a vibratory signal with an acceleration of 1.4 X 10 4 m/sec 2 RMS is recorded from the substrate. However, no sound is detected by a microphone held to within 1 cm of the stridulating ant. A similar vibratory signal is recorded from the substrate when a worker is restrained by having an antenna clamped in forceps such that the ant is free-standing on the accelerometer surface. This proves that 1980] Stuart & Bell — Leptothorax 209 the vibratory signal can be transmitted through the ant s legs to the substrate. L. muscorum workers will stridulate when restrained, fighting, dissecting insect fragments, engaging in trophallaxis with adults and larvae, and when attempting to move a larva adhering to the substrate. In addition, in food and water deprived colonies, workers will also stridulate when grooming other adults and larvae, and when consuming liquid food or water. The significance of these findings is discussed in terms of the possible function of stridulation in the above contexts. Literature Cited Adlerz, G. 1896. Myrmecologiska Studier. III. Tomognathus sublaevis Mayr. Bihang Till K. Svenska Vet. Akad. Handlingar 21(4): 1-76. Allow ay, T.M. 1980. The origins of slavery in Leptothoracine ants (Hymenop- tera: Formicidae). Amer. Nat. 115(2): 247-261. Bernard, F. 1968. Les fourmis (Hymenoptera Formicidae) d’Europe occidentale et septentrionale. Masson et Cie, Paris. 410 pp. Bhatkar, A., and W.H. Whitcomb. 1970. Artificial diet for rearing various species of ants. Fla. Entomol. 53: 217-232. Brown, W.L., Jr., 1955. The ant Leptothorax muscorum (Nylander) in North America. Entomol. News 26: 43-50. Dumortier, B. 1963. In Busnel, R. G. (ed.). Acoustical behavior of animals. Elsevier, Amsterdam, pp. 346-373, 583-654. Haskins, C.P., and E.V. Enzmann. 1938. Studies of certain sociological and physiological features in the Formicidae. Ann. N.Y. Acad. Sci. 37: 97-162. Landois, H. 1874. Thierstimmen. Herder, Freiburg. 229 pp. Marcus’ H„ and E.E. Marcus. 1951. Los nidos y los organos de Pogono- myrmex marcusi y de Dorymyrmex emmaericellus Kusn. Folia Universitaria 5: 117-143. Markl, H. 1965. Stridulation in leaf-cutting ants. Science 149: 1392-1393. Markl, H. 1967. Die Verstandigung durch Stridulationssignale bei Blattschnei- derameisen. I. Diebiologische Bedeutung de Stridulation. Z. vergl. Physiol. 57: 299-330. (English summary) Markl, H. 1968. Die Verstandigung durch Stridulationssignale bei Blattschnei- derameisen. II. Erzeugung und Eigenschaften de Signale. Z. vergl. Physiol. 60: 103-150. (English summary) Markl, H. 1970. Die Verstandigung durch Stridulationssignale bei Blattschnei- derameisen III. Die Empfindlichkeit fur Substratvibrationen. Z. vergl. Physiol. 69: 6-37. (English summary) Markl, H. 1973. The evolution of stridulatory communication in ants. Proc. 7th Congr. IUSSI, London, pp. 258-265. Markl H and B. Holldobler. 1978. Recruitment and food-retrieving beha- vio’r in’ Novomessor (Formicidae, Hymenoptera). II. Vibration signals. Behav. Ecol. Sociobiol. 4: 183-216. 210 Psyche [Vol. 87 Markl, H., B. Holldobler and T. Holldobler. 1977. Mating behavior and sound production in harvester ants (Pogonomyrmex, Formicidae). Ins. soc. 24 : 191-212. Moglich, M., W. Maschwitz and B. Holldobler. 1974. Tandem calling: a new kind of signal in ant communication. Science 186 : 1046-1047. Sharp, D. 1893. On stridulation in ants. Trans. Entomol. Soc. Lond. 1893 : 199-213. Spangler, H.G. 1967. Ant stridulations and their synchronization with abdomi¬ nal movements. Science 155: 1687-1689. Stuart, R.J. 1978. The slave-making ant, Harpagoxenus canadensis M.R. Smith, and its host species, Leptolhorax muscorum (Nylander): An ethological investigation of slave-raiding, colony foundation and slave-deprivation. Master’s thesis, University of Toronto, iii + 138 pp. Taylor, R.W. 1978. Nothomyrmecia macrops: A living-fossil ant rediscovered. Science 201 : 979-985. Wheeler, W.M. 1903. Ethological observations on an American ant (Leptolhorax emersoni Wheeler). J. Physiol. Neurol. 2: 31-47. Wilson, E.O. and R.M. Fagen. 1974. On the estimation of total behavioral repertories in ants. J. N.Y. entomol. Soc. 82: 106-112. Zhantiev, R.D. and A.V. Sulkanov. 1977. Sounds of ants of the genus Myrmica. Zool. Zh. 56 : 1255-1258. (in Russian, English summary) COMPARATIVE STUDIES OF DICTYNA AND MALLOS: V. TOLERANCE AND RESISTANCE TO STARVATION By Robert R. Jackson* North Carolina Mental Health Research Anderson Hall, Dorothea Dix Hospital Raleigh, North Carolina 27611 Introduction In recent years, there has been an increasing interest in social spiders (recent review: Krafft, 1979); and in particular, efforts have begun to compare the social adaptations that have evolved in spiders with those known for insects (Wilson, 1971). Kullmann (1968, 1972) emphasized cooperation, interattraction, and tolerance as essential characteristics that distinguish social from solitary spiders. Cooperation refers to social spiders working together in some sense, and interattraction concerns the formation of groups due to conspecific spiders attracting each other. Tolerance refers to the non-aggressive, and especially, the non-cannibalistic nature of social spiders. In a group of closely related web-building spiders from the dictynid genera Mallos and Dictyna, there is considerable interspecific variation in social organization (Jackson, 1978a). Comparative studies of these provide a means by which the particular qualities of sociality occurring in spiders can be assessed. Earlier studies have been especially concerned with interattraction (Jackson, 1981), cooperation (Jackson, 1979a), and other aspects of the biology of these spiders (e.g., Jackson, 1978b; Witt, etal., 1978). Burgess (1979) considered a particular aspect of tolerance, the vibratory stimuli that elicit predatory behavior and how these differ from the vibrations produced by conspecific spiders. The present study considers some additional questions about tolerance and related comparative aspects of the biology of dictynid spiders. Most species in these genera are solitary, living one spider per web, except for the common exception of cohabiting male-female pairs ‘Present Address: Department of Zoology, University of Canterbury, Christ¬ church 1, New Zealand Manuscript received by the editor November 12, 1980. 211 212 Psyche [Vol. 87 (Jackson, 1977). M. trivittatus, D. calcurata, and D. albopilosa are communal, territorial. They live in web complexes divided into defended web units. One or a small group of spiders occupy each unit, separated from other units by interstitial threads. M. gregalis is communal, non-territorial; and hundreds or thousands of individuals occupy single communal webs not divided into defended units (Jackson & Smith, 1978). Aggression and cannibalism are pronounced in the solitary and communal, territorial species, but almost never observed in laboratory colonies of M. gregalis which were normally provided with insect prey (adult Musca domestica or Drosophila melanogaster) once or twice per week. This raises the question of whether cannibalism would occur if the spiders were nutritionally stressed. In casual observations of small colonies kept without prey for 3-4 weeks, cannibalism was not seen (Jackson, 1979b; P. N. Witt, pers. comm.); but considering the renowned capacities of spiders to resist starvation (Anderson, 1974), it is difficult to assess the nutritional stress to which these spiders were subjected. Consequently these observations were extended by keeping colonies of M. gregalis indefinitely without alternative prey in order to see whether the spiders would resort to cannibalism before starving to death. In these observations, it was noted that adult males died sooner than the adult females and immatures. More casual observations in the laboratory also indicated that adult males of M. gregalis were more difficult to keep alive, even if provided with insect prey, and that they differed in this respect from the other species of Mallos and Dictyna. Additional observations were carried out in order to clarify this aspect of the biology of these spiders. Methods and Materials The laboratory colony of M. gregalis originated from spiders collected by J. W. Burgess (1976) near Guadalajara, Mexico. M. trivittatus were collected in Arizona and D. calcurata near Lake Chapala, Mexico, by the author (Jackson, 1978a). Two types of transparent, plastic cages were used: small ones constructed from 9-cm-diameter petri dishes; large, from 10 x 10x6 cm boxes. Details of cage design and maintenance are provided elsewhere (Jackson, 1974, 1979b). The terms “male” and “female” will be used for adults only. 1980] Jackson — Dictyna & Mallos 213 “Immatures” were always individuals 2 mm or less in body length. Females of M. trivittatus tended to be 7 mm in body length; males, 5 mm. The adults of the other two species tended to be 4-5 mm in body length. Statistical tests are from Sokal and Rohlf(1969). Transformations were carried out with the Mann-Whitney tests that permitted the use of tables for the Student t-statistic. MAINTENANCE OF MALLOS GREGALIS WITHOUT INSECT PREY Eight colonies were set up in large cages. Two males, two females, and two immatures were placed in each. The colonies were provided with Musca for two weeks, then all fly carcasses were removed. Any spider that died during this preliminary period was removed and replaced with another individual of the same sex/age class. Subse¬ quently, the colonies were maintained without insect prey until all spiders were dead. Each colony was observed for at least 5 min three times per day. morning, early afternoon, and late afternoon or evening. Elowever, periods of observation were generally much longer than this, since the colonies were kept on or near my desk and observed intermittently throughout the day when I was present. MAINTENANCE WITH INSECT PREY For these observations, the spiders were kept individually in small cages for 30 days and provided either one Musca or five Drosophila once per week. Each spider constructed its own web during the 30- day observation period. In addition to the total of 135 males referred to in Table 1 and to the 80 females and immatures of M. gregalis referred to in Table 2, 40 females and 40 immatures each of M. trivittatus and D. calcurata were set up. Twenty of each class were provided Musca; the other 20, Drosophila. In another 130 cases, females of M. gregalis were placed one per cage, then left for one week. One male M. gregalis was then placed in each cage and provided Musca (60) or Drosophila (70) as described above. In half of each of these groups, the females were removed before the male was introduced into the web. 214 Psyche [Vol. 87 Results and Discussion TOLERANCE Well-fed M. gregalis are tolerant (i.e., non-cannibalistic and non- aggressive), and the present study indicates that they remain tolerant to what seems the ultimate extent: when kept without alternative prey, they starve to death rather than resort to cannibalism. No M. gregalis was seen feeding on conspecifics, and none of the dead ones had the appearance of having been eaten. When spiders contacted other living or dead conspecifics, they simply walked away, either immediately or after briefly tapping with their legs. Although it is tempting to view the absence of cannibalism in M. gregalis as altruistic and to entertain familiar hypotheses such as kin selection (e.g., Wilson, 1971), a cautionary remark seems appropriate. Few observations have been made on these spiders in their natural habitats, and how often colonies encounter shortages of insect prey is unknown. However, considerations of this sort seem important in assessing whether, and if so to what extent, tolerance is altruistic, especially since the issue is not something the spiders do but something they fail to do. SEX AND SPECIES DIFFERENCES IN SURVIVAL In the colonies left indefinitely without insect prey, males died sooner than females (Fig. 1; Mann-Whitney U-test, t = 5.599, P< 0.001). No males survived beyond 23 days, although females and immatures survived as long as 53 days. There were no evident differences in survival times for females and immatures. Male spiders may generally be adapted to a lifestyle that emphasizes courtship, mating, and searching for females at the expense of maintenance functions that serve to prolong survival (Ghiselin, 1974; Jackson, 1978c). The earlier deaths of males in colonies maintained without prey would seem to be a reflection of this in M. gregalis. Perhaps males lack the capacity to store nutrients to get them through periods without prey, or possibly they are behaviorally and/or physiologically more active and require greater amounts of nutrients per unit time than females and immatures. However, the difficulty in keeping males of M. gregalis alive seems also to be a reflection of differences in the biology of this and the other two species. When provided in their own webs with insect prey, many males of M. gregalis died; but only a few of those of the other 1980] Jackson — Dictyna & Mallos 215 Days Fig. 1. Frequency distributions for Mallos gregalis showing the numbers of individuals that died after different numbers of days without insect prey. Spiders kept in colonies. See text for details. 3: from the first until the fifth day without insect prey. 8: from the sixth until the tenth day without insect prey, etc. Note: males died sooner than females and immatures. 216 Psyche [Vol. 87 species died (Table 1). When maintained with insect prey, survival rates for all sex/age classes of M. trivittatus and D. calcurata were high. (No females of either species died during the 30-day period. Only 3 immatures of M. trivittatus and one of D. calcurata died. For the males, see Table 1.) Table 1. Adult males of three different species maintained for 30 days with either Musca domestica or Drosophila melanogasler provided as prey. G-tests of indepen¬ dence, with Yates Correction, carried out separately for survival rates of those provided with each of the two types of prey: P < 0.001. Prey Species Number of Males Survived Died Total G Mallos gregalis 12 8 20 Musca Mallos trivittatus 20 0 20 15.864 Dictyna calcurata 19 1 20 Mallos gregalis 21 14 35 Drosophila Mallos trivittatus 19 1 20 20.008 Dictyna calcurata 20 0 20 Since males of M. gregalis lack functional cribella (Jackson, 1979a), their webs are not adhesive and evidently not very effective in prey capture; no males were observed feeding in their own webs. However, males of M. trivattatus and D. calcurata, which also lack functional cribella (unpub. obs.), were observed feeding in their own webs. Perhaps males of M. gregalis rarely move off the large communal webs containing females and immatures. In contrast, while searching for mates, males of M. trivittatus and D. calcurata may spend considerable time away from webs containing females and immatures; and capabilities of capturing prey without the use of, adhesive webs may be adaptations related to this. Within 30 days, all males died in the colonies kept without insect prey, but more than half survived in their own webs when insects were available. This suggests that males may have fed at times other than when observed, perhaps by scavenging on insects that died in their cages. 1980] Jackson — Dictyna & Mallos 217 Dependence on conspecifics for survival seems more pronounced for the males of M. gregalis than for the females and immatures. Although individuals of M. gregalis normally feed and construct their webs in groups, females and immatures have functional cribella; and they can construct and use adhesive webs to capture insects alone. Thus, males of M. gregalis died more frequently than females and immatures of this species when in their own webs (Table 2). Few males of M. gregalis died when kept for 30 days with females (Table 3); and often they were observed feeding, alone or with the females, on both Musca and Drosophila. When alone in webs built by females, few of the males provided with Drosophila, but many of those provided with Musca, died. Musca often adhered to the webs; but unlike the Drosophila, they usually struggled violently; and the males were sometimes seen running from them. With females present, males were seen joining the other spiders to feed on Musca whose struggles had begun to subside but not to begin feeding alone on struggling flies. Possibly at least a partial explanation for the differences in survival in Table 3 can be found in this cautious behavior of the males. Table 2. Adult males, adult females, and immatures of Mallos gregalis maintained for 30 days with either Musca domestica or Drosophila melanogaster provided as a prey. G-tests of independence, with Yates Correction, carried out separately for survival rates of those provided with each of the two types of prey: P < 0.001. Prey Sex/Age Class Number of Spiders Survived Died Total G Males 12 8 20 Musca Females 20 0 20 13.110 Immatures 16 4 20 Males 21 14 35 Drosophila Females 19 1 20 12.226 Immatures 18 2 20 218 Psyche [Vol. 87 Table 3. Adult males of Maliosgregalis maintained for 30 days in different types of webs with either Musca domestica or Drosophila melanogaster provided as prey. G- tests of independence, with Yates Correction, carried out separately for survival rates of those provided with each of the two types of prey: P < 0.001. Prey Type of Web Number of Males Survived Died Total G Built by the Male 12 8 20 Musca Built by a Female Female Absent 11 9 20 21.508 Built by a Female Female Present 39 1 40 Built by the Male 21 14 35 Drosophila Built by a Female Female Absent 33 2 35 16.380 Built by aFemale Female Present 32 3 35 Summary 1. When kept without alternative prey, individuals in colonies of the communal, non-territorial spider Malios gregalis starved to death rather than resort to cannibalism. 2. Males of M. gregalis died sooner than females and immatures when kept without prey. 3. Compared with males of the communal, territorial species M. trivittatus and Dictyna calcurata, males of M. gregalis did not survive as long without prey when maintained in their own webs. 4. With prey ( Musca and Drosophila) provided, males of M. gregalis survived longer when sharing webs with females than when alone. 5. With small prey ( Drosophila ) provided, males survived longer alone in webs built by females than alone in their own webs. Acknowledgements The assistance of Peter N. Witt during all phases of this work is gratefully acknowledged. Yael Lubin provided helpful comments on 1980] Jackson — Dictyna & Mallos 219 the manuscript. I thank Mary Catharine Vick for assistance with the preparation of the manuscript. Charles Griswold, Steve Jackson, and Vincent Roth assisted in locating spiders in the field. Helpful discussions and assistance in identifying specimens were provided by Willis Gertsch. The assistance of the Southwestern Research Station of the American Museum of Natural History is gratefully acknow¬ ledged. This work was supported in part by National Science Foundation Grant BMS 75-09915 to P. N. Witt. Literature Cited Anderson, J. F. 1974. Responses to starvation in the spiders Lycosa lenta Hentz, and Filistata hibernalis (Hentz). Ecology 55: 576-585. Burgess, J. W. 1976. Social spiders. Sci. Amer. 234: 100-106. 1979. Web-signal processing for tolerance and group predation in the social spider Mallos gregalis Simon. Anim. Behav. 27: 157-164. Ghiselin, M. T. 1974. The Economy of Nature and the Evolution of Sex. University of California Press: Berkeley. Jackson, R. R. 1974. Rearing methods for spiders. J. Arachnol. 2: 53-56. 1977. Web sharing by males and females of dictynid spiders. Bull. Br. Arachnol. Soc. 4: 109-112. 1978a. Comparative studies of Dictyna and Mallos (Araneae, Dictynidae): I. Social organization and web characteristics. Rev. Arachnol. 1: 133-164. 1978b. Male mating strategies of dictynid spiders with differing types of social organization. Symp. Zool. Soc. Lond. 42: 79-88. 1978c. Life history of Phidippus johnsoni (Araneae, Salticidae). J. Arachnol. 6: 1 29. 1979a. Predatory behavior of the social spider Mallos gregalis: Is it cooperative? Ins. Soc. 26: 300-312. 1979b. Comparative studies of Dictyna and Mallos (Araneae, Dictynidae): II. The relationship between courtship, mating, aggression and cannibalism in species with differing types of social organization. Rev. Arachnol. 2: 103-132. 1981. Comparative studies of Dictyna and Mallos (Araneae: Dictynidae): IV. Silk-mediated interattraction. Ins. Soc. In press. Jackson, R. R. & S. E. Smith 1978. Aggregations of Mallos and Dictyna: Population characteristics. Psyche 85: 65-80. Krafft, B. 1979. Organisation et evolution des societes d’araignees. J. Psychol. 1: 23-51. Kullmann, E. 1968. Soziale Phaenomene bei Spinnen. Ins. Soc. 15: 289-298. 220 Psyche [Vol. 87 1972. Evolution of social behavior in spiders (Araneae: Eresidae and Theridii- dae). Amer. Zool. 12 : 419-426. Sokal, R. R. & F. J. Rohlf 1969. Biometry. Freeman: San Francisco. Wilson, E. O. 1971. The Insect Societies. Belknap Press: Cambridge, Mass. Witt, P. N., M. B. Scarboro, & D. B. Peakall 1978. Comparative feeding data in three spider species of different sociality: Araneas diademalus Cl., Mallos trivattatus (Banks), and Mallos gregalis (Simon). Symp. Zool. Soc. Lond. 42 : 89-97. NOTES ON THE NESTS AND PREY OF SIX SPECIES OF PISON IN AUSTRALIA (HYMENOPTERA: SPHECIDAE) By Howard E. Evans, 1 Robert W. Matthews, 2 and Allan Hook 1 In the course of studies on the behavior of ground-nesting Sphecidae in Australia, we have occasionally made observations on species that make free mud nests or that accept wooden trap nests (see Krombein, 1967, for technique). Chief among these are species of the genus Pison, which is abundantly represented in Australia. We report here on six species, four of which have not previously been studied (rufipes Shuckard, westwoodi Shuckard, marginatum Smith, and a species near tibiale Smith). Data on two additional species ( ignavum Turner and spinolae Shuckard) confirm and enlarge upon previously published reports. Our specimens have been compared with identi¬ fied material in the British Museum (Natural History), including the types of Smith’s and Turner’s species. Voucher specimens have been deposited in the Australian National Insect Collections, Canberra, and at the University of Queensland, Brisbane. Some of these observations were made by Evans and Matthews during the summer of 1969-70, others by Evans and Hook during the summer of 1979-80. Pison rufipes Shuckard Nests of this species were located on three occasions near Brisbane, Queensland. The first two were found early in the summer (1-2 November 1979) on roots dangling from the top of steep, overhang¬ ing earthen banks not far from water. The third nest was found on the pendant branch of a tree close to water on 9 March 1980, and was doubtless made by a female of a second generation. All nests were made of dried mud and were spindle-shaped, with the long axis perpendicular to the ground, and were so covered with mud on the outside that individual cells could not be discerned on the surface. The nest on a living branch presented quite a different appearance 'Department of Zoology and Entomology, Colorado State University, Fort Collins, Colorado 80523. department of Entomology, University of Georgia, Athens, Georgia 30602. Manuscript received by the editor February 12, 1981. 221 222 Psyche [Vol. 87 from the others, since the wasp had incorporated the leaf bases into its nest. The first nest, collected near Blunder Creek, in the southern part of the city of Brisbane, was actually a group of three nests on roots only a few cm apart; we have no way of knowing whether or not all were made by one female. The three nests varied in length from 4 to 6.5 cm and all were about 2 cm wide at their maxima (Fig. 2). Over the next few weeks 16 wasps emerged from the three nests, each leaving an emergence hole about 3 mm in diameter. The second nest was a set of two nests, of form very similar to the first set, one 2.5 cm wide and 5 cm long, the other 2 cm wide and 6.5 cm long. This nest was collected along the Brisbane River near Somerset Dam, some 60 km NW of Brisbane. Over the next few days we reared from this nest 3 P. rufipes, 2 P. westwoodi, and a miltogrammine fly, Pachyophthalmus sp. We believe that westwoodi had probably appropriated cells in a nest constructed by rufipes, as that species is known to occupy hollow cavities (see below). The third nest was collected in late-summer, also at Blunder Creek, Brisbane. It was similar in shape to the others, 7.5 cm long by 2 cm wide, but had several leaves protruding from it (Fig. 1). This nest was on a pendant Acacia branch about 1.3 m above the ground and a short distance from the edge of a backwater of Blunder Creek. When this nest was found a female was plastering mud over the outside; she was taken for identification. The nest was dissected and found to contain ten cells, all broadly elliptical, 6.5-8 mm in diameter and 8.5-12 mm in length. Each was separated by at least 2 mm of mud and from the outside of the nest by about 7 mm of mud. The number of spiders per cell varied from 4 fairly large ones to 9 small ones (x=7.1). Four cells contained an egg, in each case laid longitudinally, laterally on the base of the abdomen of one of the spiders. The remaining 5 cells contained wasp larvae of various sizes. All of the 47 spiders preserved proved to be Salticidae, of the following species: Euryattus bleekeri (Doleschall)—24 Jotus braccatus Koch—5 Saitis nigriceps (Keyserling)—18 1980] Evans, Matthews, & Hook — Pison in Australia 223 Figs. 1-6. 1. Nest of Pison rufipes on Acacia branch. 2. Nests of P. rufipes attached to pendant roots. 3. Egg of P. marginatum on prey, bearing a parasitoid larva. 4. Nest of P. ignavum on Banksia leaf. 5. Egg of P. spinolae on prey. 6. Egg of P. marginatum on prey. 224 Psyche [Vol. 87 Pison ignavum Turner This is a widely distributed species in the Australian zoogeographic region. Williams (1945) found that in New Caledonia this species “constructs free cells of mud pellets and sometimes hangs them from rootlets exposed in a bank". We collected a nest plastered to the underside of a Banksia leaf overhanging a stagnant pool a few meters from Blunder Creek, Brisbane, in Eucalyptus-Melaleuca woodland, not far from the first nest of P. rufipes, cited above. This nest was 4.5 cm long, 3.1 cm wide, and 0.8 cm deep; it occupied about a third of the area of the leaf (Fig. 4). Seven cells could be faintly discerned beneath the lumpy surface of gray mud. This nest was collected in late November, 1979; about a month later 5 P. ignavum emerged, each leaving a small hole about 3 mm in diameter. Pison westwoodi Shuckard This very small species was reported above as having been reared from a nest of P. rufipes, where it had possibly usurped some cells or added cells to a completed nest. Evidently it utilizes various pre¬ existing cavities, as we also reared the species from three trap nests set up near Canberra, Australian Capital Territory, in December 1969 and February 1970. All three trap nests had a bore diameter of 4.5 mm, the smallest bore employed. A nest set out near the Murrum- bidgee River had three cells, 9-14 mm in length, separated by mud partitions 1-2 mm thick; these were separated from the entrance to the boring by a long, empty cell, which was closed off by a thick mud plug. The cells contained cocoons when collected, and these gave rise to three adults the following spring. The second nest, on the window ledge of a house in Canberra, contained seven cells, varying in length form 6.5 to 12.5 mm. All contained larvae and the remains of spiders when the nest was collected in mid-December; several adult wasps emerged in late January. The third trap nest had been set on top of a fence rail not far from the preceding. It was sealed in mid-December and opened on 28 December. There were four cells, 6.5-12.5 mm in length, separated by thin mud partitions. The two innermost cells contained many tiny spiderlings, 19 and 30 per cell; evidently the egg had failed to hatch in these cells. The two outermost cells contained cocoons, one of which gave rise to a male on 27 January. Cocoons of this species measure 1980] Evans, Matthews, & Hook — Pison in Australia 225 6.5-8 mm in length and are light brown in color, of thin, parchment¬ like material (Fig. 7). Pison marginatum Smith This species also made use of trap nests in the Canberra area during 1969-70, but the three nests we found all occupied larger borings, 6-7 mm in diameter. A nest collected near the Murrumbidgee River on 1 February contained cocoons which gave rise to adults on 20 March, while a second nest collected in the same area on 7 March contained eggs and larvae on the prey and ultimately produced adult wasps the following September. A third nest, on Black Mountain, Canberra, contained cocoons when harvested 24 March and also gave rise to adults the following September. Thus there are evidently two generations a year in the Canberra area. The three nests had from 4 to 7 cells each, the cells measuring from 12 to 19 mm in length and separated by mud partitions 1-2 mm thick. Two of the nests were closed off by thick mud plugs, 17-18 mm thick; the third had an empty vestibular cell 30 mm long, closed off by a thin plug which was recessed 7 mm from the bore opening. This last nest was abundantly supplied with small spiders, 5 to 9 per cell. Four of the cells contained eggs, in each case laid longitudinally on the abdomen of a spider close to the cell entrance, suggesting that it was laid on the last spider placed in the cell (Fig. 6). The following spiders were identified: ARANEIDAE: Gea theridioides (Koch)—7 99 Araneus lutulenta (Keyserling)— 1 immature OXYOPIDAE: Oxyopes elegans Koch—1 9 One cell from the Murrumbidgee River nest collected on 7 March had a small parasitoid larva feeding on the host egg (Fig. 3). We did not rear this successfully. Callan (1979) has reported the rhipiphorid beetle Macrosiagon diversiceps (Blackburn) as a parasitoid of the related species P. spinolae, and we suspect that the larva we observed was that of a rhipiphorid. The cocoons of marginatum measure 11-13 mm in length and are of a darker shade of gray-brown than those of westwoodi, and the walls appear thicker and firmer (Fig. 9). Pison spinolae Shuckard This is a relatively large species of Pison which has been introduced from Australia into New Zealand, where it is especially common. 226 Psyche [Vol. 87 Callan (1979) has recently reviewed what is known of the nesting behavior and natural enemies of this species. Evidently mud cells are constructed in a variety of protected situations, often around houses, and spiders of the family Araneidae are used as prey. We reared P. spinolae from two trap nests placed on windowsills of a house in Canberra. Both were completed in late November, 1969; one was opened at that time and found to contain spiders bearing eggs or larvae, while the second was opened 18 December and found to contain cocoons. Adults emerged from both in late January. Both were in borings 8 mm in diameter. The number of cells per nest was 4-6, cell length 13-26 mm, not including one cocoon in a very long cell in the deepest part of the boring, 61 mm long. The cells were separated by thin mud partitions and the nests closed off with plugs 2-4 mm thick. One nest had a 3 mm long vestibule cell between the last cell partition and the outer plug. Both nests had mud plugs at the extreme inner end of the boring. The number of spiders per cell varied from 5 to 12, and the egg was placed dorsolaterally near the front of the abdomen of the spider closest to the entrance to the cell (Fig. 5). Several were saved for identification, and all proved to be Araneidae, as follows: Araneus brisbanae (Koch)—1 $ Araneus transmarinus (Keyserling)—4 immatures Singotypa sp.—1 $, 1 immature Cocoons of this species measure from 10.5 to 13.5 mm in length (giving rise to males) and from 15.5 to 17.5 mm in length (giving rise to females). They differ in color from those of the preceding two species in being brown and distinctly darker at the anterior, more blunt end (Fig. 8). Pison species near tibiale Smith We reared individuals of this species from four trap nests, two set up on Black Mountain, Canberra, and two along the Murrumbidgee River in Australian Capital Territory. All were in bores 6-7 mm in diameter; one contained five cells, the other three seven each. Cells measured 12-20 mm in length and were separated by mud partitions 0.5-1.2 mm thick. Three of the nests had no outer plug when collected and were closed merely with the thin partition of the outermost cell, which was recessed 16-20 mm from the bore opening. One had a mud plug 10 mm thick, flush with the opening. A nest collected on 1 1980] Evans, Matthews, & Hook — Pison in Australia 227 Figs. 7-10. Cocoons of Pison species in trap nests, not equally enlarged (see text for measurements). 7. P.westwoodi. 8. P.spinolae. 9. P. marginatum. 10. P. species near tibiale. 228 Psyche [Vol. 87 February had larvae in all cells, the larvae being progressively smaller toward the entrance. The spiders in this nest appeared very diverse, but were not saved. The other three nests, collected 10 February-26 March, contained nothing but cocoons aside from three cells in which the egg had evidently failed to hatch; these contained 5-6 spiders each, all of them Cymbacha festiva Koch (3 $$, 1 13 immatures) (Thomisidae). Cocoons of this species measure 11-13 mm in length and are quite different in form frc/m those of the preceding three species, being abruptly widened at the anterior end (Fig. 10). Although our specimens key readily to tibiale in Turner’s (1916) review, our impression is that several species are now being confused under that name. Our voucher specimens, in the Australian National Insect Collections, Canberra, should enable our material to be associated with the correct species name when a much-needed revision of the Australian species is available. Discussion The Australian species of the genus Pison evidently fall into three discrete groups with respect to nesting behavior. Members of the first group build free mud nests consisting of several cells attached to stems, roots, or leaves and coated with mud in such a way that the cells are not individually discernible on the surface. The two species rufipes and ignavum belong to this group, and it is noteworthy that both belong to a species-group in which the second recurrent vein is received at the middle of the second submarginal cell, rather than near its apex as in most Pison species. The prey of rufipes was found to consist of Salticidae. The remaining species considered here (westwoodi, spinolae, marginatum, and sp. nr. tibiale) all accept hollow,^ubular trap nests, although there is evidence that the first two are somewhat more versatile in their nesting behavior. Cells are separated by thin mud partitions and the nest is often closed off with a thick mud plug. These species appear to make extensive use of orb-weaving spiders, most records being for Araneidae, although there is one record for Oxyopidae and several for Thomisidae. The cocoons show interest- ing species differences, not unlike those found among North American species of the related genus Trypoxylon (Krombein, 1967; Matthews and Matthews, 1968). These cocoon differences are summarized in Table I. 1980] Evans, Matthews, & Hook — Pison in Australia 229 Table I. Major features of cocoons of four species of Pison. Species Size (mm) Color Shape westwoodi 6.5-8.0 Light brown Cylindrical, more rounded at posterior end than at anterior end marginatum 11-13 Dark gray- brown Like preceding, but walls less thin and delicate spinolae 10.5-17.5 Brown but much darker at anterior end Same as marginatum nr. tibiale 11-13 Brown but paler at anterior end Abruptly expanded at anterior, blunt end A third group of species nests in the ground and does not use mud at any stage of nest construction; species, of this group have a well developed psammophore which is used in carrying soil from the nest (Evans, 1981). Prey consists of Oxyopidae except in one species that nests in firm clay-sand (auriventre Turner) and was found to use Lycosidae. Turner (1916) recognized aDOUt 50 species of Pison from Australia, and there are undoubtedly many more to be described. On the basis of the few species so far studied, the group appears to be a most rewarding one from the point of view of comparative behavior. It will be interesting to discover to what extent morphological differences parallel those in behavior and how much behavioral flexibility exists among the various species. Acknowledgments The 1969-70 studies of Evans and Matthews were supported by a grant from the National Science Foundation, no. GB8746. During the summer of 1979-80 Evans held a research fellowship at the Department of Entomology, University of Queensland, and a travel grant from the National Geographic Society, while Hook had a grant for dissertation research from the National Science Foundation, no. BNS79-12602. The spiders from the Canberra area were identified by M. R. Gray of the Australian Museum, Sydney, those from Queensland by V. Davies and R. McKay of the Queensland Museum, Brisbane. 230 Psyche [Vol. 87 References Callan, E. McC. 1979. The Sphecidae (Hymenoptera) of New Zealand. New Zealand Ent 7- 30-41. Evans, H. E. 1981. Biosystematics of ground-nesting species of Pison in Australia (Hymen¬ optera: Sphecidae: Trypoxylini). Proc. Wash. Ent. Soc. (in press). Krombein, K. V. 1967. Trap-Nesting Wasps and Bees: Life Histories, Nests, and Associates. Smithsonian Press. 570 pp. Matthews, R. W. and J. R. Matthews 1968. A note on Trypargilum arizonense in trap nests from Arizona, with a review of prey preferences and cocoon structure in the genus (Hymen- opteraa, Sphecidae). Psyche 75: 285-293. Turner, R. E. 1916. Notes on the wasps of the genus Pison, and some allied genera. Proc. Zool. Soc. London 1916: 591-629. Williams, F. X. 1945. The aculeate wasps of New Caledonia, with natural history notes. Proc. Hawaiian Ent. Soc. 12: 407-452. THE “EDGE EFFECT” IN SCHIZOCOSA OCREATA (ARANEAE: LYCOSIDAE): A REASSESSMENT By Alan B. Cady 1 , William J. Tietjen 2 , and George W. Uetz 3 Introduction The relationship between local spider distribution patterns and environmental factors has been studied in a variety of species (N0rgaard 1951; Dondale et al. 1969; Hallander 1970; Edgar 1971; Riechert 1974, 1976; Uetz 1976; Dondale 1977). Aspey (1976) stated that Schizocosa ocreata (Walckenaer) (formerly crassipes; Dondale and Redner 1978) was found in aggregations along a woodland-field ecotone, and suggested that unique microclimatic conditions and social interactions among conspecifics occurring within this area resulted in an “edge effect” for this spider’s distribution. He termed S. ocreata an “edge” species, implying it was found almost exclu¬ sively along ecotones. We were skeptical of Aspey s (1976) conclu¬ sions, since previous literature and prior experience with this species led each of us to the separate conclusion that S. ocreata is a forest¬ dwelling spider (Kaston 1948; Dondale and Redner 1978; Uetz 1976; Cady (in prep.)). In addition, Aspey’s (1976) survey for S. ocreata appeared incomplete, as he did not report sampling within the adjacent woodland or field. Considering Aspey’s (1976) elaborate behavioral arguments based on assumptions about the distribution of this species, we felt further study was necessary. Methods The study site was approximately 3.5 km west from Aspey’s (1976) site. Three areas were sampled: A mixed hardwood deciduous woodland ( Quercus sp., Liriodendron sp., Fraxinus sp., Fagus sp.), the adjoining ecotone, and an open goldenrod-thistle field ( Solidago sp., Cirsium sp.). Spiders were sampled by twelve pitfall traps of the type described by Uetz and Unzicker (1976). Three were set in the 1. Dept, of Zoology. Ohio University, Athens, Ohio45701 (Present Address: Dept, of Zoology, University of Tennessee, Knoxville, Tenn. 37916) 2. Georgia College, Milledgeville, Georgia 31061 3. Dept, of Biological Sciences, Univ. of Cincinnati, Cincinnati, Ohio 45221 Manuscript received by the editor January 20, 1981 231 232 Psyche [Vol. 87 woodland, four in the ecotone, and five in the field. The trap contents were collected seven times between 13 May and 21 June 1977. Results More male S. ocreata were captured than females (* 2 = 109.87, 1 df P<0.001), probably because this time of year was the breeding season for S. ocreata, and male lycosids are more motile than females (Vlijm and Richter 1966; Hallander 1967). Unequal numbers of males, females, and total (males + females) spiders were found across all three habitats (woods, ecotone, field) due to the relatively low number of spiders found in the field (Table 1). The number of males and total number of spiders did not differ between the woods and ecotone; the greatest number of females were found in the woods (Table 1). Table 1. Numbers of male, female, and total Schizocosa ocreata found in woods, ecotone, and field. Underlined values indicate equality (Chi-square test for Goodness- of-Fit P > 0.05). All Chi-square tests were adjusted for sample size (ns). Woods Ecotone Field nj=3 nj=4 ni=5 Males 58 83 29 Females 12 6 6 Total 70 89 35 Discussion Our data indicates that the distribution of S. ocreata was not restricted to the ecotone, as there was no difference between the number of spiders found in the woods and ecotone. Fewer spiders, however, were found in the field as compared to the other areas, probably chie to the lack of cover and to temperature/mositure extremes in this habitat. Cady (in prep.) worked with a dense population of S. ocreata that was found deep within a woodland site not far (< 50m) from Aspey’s (1976) study site. The spiders in the 1980] Cady, Tietjen, & Uetz — Schizocosa 233 woods were found in leaf litter (depth 4-6 cm) and under a herbaceous “microcanopy” immediately adjacent to a spring seepage, while the spiders along Aspey’s ecotone were in a depressed area where leaf litter and moisture collected. The greatest number of spiders in the present study were found in areas with similar characteristics. Such microhabitats provide both soil moisture and protective cover (i.e., herbaceous growth and leaf litter). In addition, deep litter may also provide the high prey density needed for egg production by females (Uetz 1975, 1979). Tietjen (1979) suggested that airborne pheromones may be involved in attracting S’, ocreata to particular areas for courtship and copulation. Such pheromones might be expected to collect under the leaves occupied by the relatively sendentary females. This may explain the denser concentrations of this spider and the social attractions Aspey (1976) proposed. We therefore agree with Aspey’s premises that microclimate and possible social attractions are determining factors for S. ocreata’s pattern of local distribution; however these microclimates or areas of congregation are not unique to ecotones, and S. ocreata should not be termed an “edge” species. Literature Aspey, W. P. 1976. Behavioral biology of the “edge effect” in Schizocosa crassipes (Araneae: Lycosidae). Psyche 83: 42-50. Cady, A. B. Microhabitat selection and locomotor activity of Schizocosa ocreata (Araneae: Lycosidae) (in preparation). Dondale,C. D. 1977. Life histories and distribution patterns of hunting spiders (Araneae) in an Ontario meadow. J. Arachnol. 4: 73-93. Dondale, C. D. and J. H. Redner 1978. Revision of the Nearctic wolf spider genus Schizocosa (Araneida:Lycosidae). Can. Ent. 110: 143-181. Dondale, C. D., J. H. Redner, E. Farrell, R. B. Semple, and A. L. Turnbull 1969. Wandering of hunting spiders in a meadow. Bull. Mus. Nat. Hist. Naturelle 41: 61-64. Edgar, W. 1971. The life cycle, abundance, and seasonal movement of the wolf spider, Lycosa (Pardosa) lugubris, in central Scotland. J. Anim. Ecol. 40: 303-322. Hallander, H. H. 1967. Range and movements of the wolf spider Pardosa chelata (O.F. Muller) and P. pullata (Clerck). Oikos 18: 360-364. 234 Psyche [Vol. 87 1970. Environments of the wolf spiders Pardosa chelala (O.F. Muller) and Pardosa pullata (C lerck). Ekol. Polska. 18: 1-17. Kaston, B. J. 1948. The spiders of Connecticut. State Geological and Nat. Hist. Surv., Bull. No. 70. 874 pp. N0RGAARD, E. 1951. On the ecology of two lycosid spiders (Pirala piraticus and Lycosa pullata) from a Danish Sphagnum bog. Oikos 3: 1-21. Riechert, S. E. 1974. The spatial pattern of local web distribution in a desert spider: Mechanisms and seasonal variation. J. Anim. Ecol. 43:733-746. 1976 Website selection in the desert spider Agelenopsis aperta. Oikos 27: 311-315. Tietjen, W. J. 1979. Tests for olfactory communication in four species of wolf spiders (Araneae,Lycosidae). J. Arachnol. 6: 197-206. Uetz, G. W. 1975. Temporal and spatial variation in species diversity of wandering spiders (Araneae) in deciduous forest litter. Environ. Entomol. 4: 719-724. 1976. Gradient analysis of spider communities in a streamside forest. Oecologia 22: 373-385. 1979. The influence of variation in litter habitats on spider communities. Oecologia 40: 29-42. Uetz, G. W. and J. Unzicker 1976. Pitfall trapping ecological studies of wandering spiders. J. Arachnol. 3: 101 - 111 . Uetz, G. W. and G. Denterlein 1979. Courtship behavior, habitat, and reproductive isolation in Schizocosa rovneri Uetz and Dondale (Araneae:Lycosidae). J. Arachnol. 7: 121-128. Vlijm, B. and C. J. J. Richter 1966. Activity fluctuations of Paradosa lugubris (Walckenaer), Araneae:Lycosi¬ dae, during the breeding season. Ent. Beri. 26: 222-230. DIFFERENCES IN NEST ARCHITECTURE BETWEEN THE NEOTROPICAL ARBOREAL TERMITES NASUTITERMES CORNIGER AND NASUTITERMES EPHRATAE (ISOPTERA: TERMITIDAE) By Barbara L. Thorne Museum of Comparative Zoology Harvard University Cambridge, Massachusetts 02138 Introduction Nests of the Neotropical termites Nasutitermes corniger (Mot- schulsky) and N. ephratae (Holmgren) have distinctive external and internal architectures. The differences are useful field characters because they are apparent in all but the smallest (<15 cm diameter) nests. N. corniger and N. ephratae are sympatric throughout much of their range. N. corniger has been reported from Mexico (Snyder 1949), Guatemala (Becker 1953), Honduras (Snyder 1949), Costa Rica (Holmgren 1910, Snyder 1925), Panama (Motschulsky 1855, Banks 1918), Venezuela (Snyder 1959), and Bolivia (Snyder 1926). N. ephratae reportedly ranges from Mexico (Becker 1961) to Brazil (Mathews 1977), with collections from Honduras (Snyder 1949), Costa Rica (Snyder 1925), Panama (Banks 1918), Venezuela (Snyder 1959), Trinidad (Snyder 1949), Guyana (Banks 1918, Emerson 1925), Surinam (Holmgren 1910, Emerson 1925), and Bolivia (Snyder 1926). Both N. corniger and N. ephratae build arboreal carton nests in lowland habitats. 1 The general structure of arboreal Nasutitermes nests has been described by Emerson (1938) and Noirot (1970). The bumpy exterior carton of N. corniger nests was distinctive to early isopterists working in Panama (Dudley & Beaumont 1889a,b; Dietz & Snyder 1923; Snyder & Zetek 1924). N. ephratae nests were described briefly by Becker (1953) and by Mathews (1977). Dietz and Snyder (1923) apparently found N. ephratae colonies in 1 N. ephratae is also capable of building mounds (pers. obs. from a savannah near Barinas, Venezuela). Manuscript received by the editor February 18, 1981. 235 236 Psyche [Vol. 87 the field only rarely, but they conclude, “In texture and general internal structure the nests and runways of N. ephratae are insep¬ arable from those of N. corniger". Based on a larger sample size, this paper presents evidence that colonies of the two species can be distinguished solely on the basis of nest architecture. This study is based on work done in Costa Rica and the Republic of Panama. Entire Nasutitermes nests of a variety of sizes were collected, measured, weighed, and completely dissected. Data pre¬ sented in this paper are based on 102 N. corniger colonies and 29 N. ephratae colonies collected in second-growth areas near Barro Colorado Island, Panama. Less quantitative but corroborating observations were made at La Selva, Sirena, and Llorona, Costa Rica and in a variety of places in central Panama. Both species of termite were identified by Dr. Kumar Krishna at the American Museum of Natural History, N.Y. In addition, specimens of N. corniger compare favorably with the syntype specimens (Museum of Comparative Zoology, Harvard University). Morphological differences between the two species are distinct among alates or reproductives, but subtle when comparing soldiers. N. corniger alates have black wings, dark bodies, and ocelli which are located relatively far from the eyes (by a distance of about twice the diameter of an ocellus) (Banks 1918, Dietz & Snyder 1923, Snyder 1959). N. ephratae alates have yellow-brown wings, brown bodies, and ocelli located close to the eyes (Banks 1918, Emerson 1925, Snyder 1959, Mathews 1977). Soldiers are differentiated on the basis of head shape (Banks 1918) or amount of tergal pubes¬ cence (Snyder 1959), but these differences are not always prominent. In alcohol, N. ephratae soldier heads turn reddish-brown while heads of N. corniger soldiers remain a rich, dark brown (pers. obs.). Voucher specimens from this study have been deposited at the Museum of Comparative Zoology (N. corniger nest numbers 3, 4, 23, 46, 80; N. ephratae nest numbers 22, 28, 31, 92). Differences in External and Internal Architecture The dark brown surface of an N. corniger nest is coarse with small bumps covering the entire exterior [Figure la]. Nests tend to be roughly spherical when small (diameter C20 cm), and grow more ellipsoidal as they enlarge. (The largest N. corniger nest dissected in this study was 68 X 46 X 34 cm 3 ; 28.0 kilos.) Localized additions to 1980] Thorne — Nasutitermes 237 Figure 1. A. N. corniger nest; B. N. ephratae nest. Note the differences in surface texture and contour. the nest may generate lobes on the contour of the surface. N. ephratae nest exteriors are a lighter brown and distinctly smoother than N. corniger surfaces [Figure lb]. The form of N. ephratae surface carton creates a leathery appearance. Nests of N. ephratae are more evenly spherical or ellipsoidal than N. corniger nests. The smooth, rotund silhouette is reformed by the termites if a portion of the nest is damaged or enlarged. Internally, N. corniger nests are heavily reinforced (with thick, dense carton) around the queen cell [Figure 2a]. The queen’s chamber measures from 1.5 to 8.0 cm at its maximum width, and from 0.6 to 0.9 cm in height. The queen cell is usually located in a central portion of the nest, often near (and sometimes within) the tree trunk or branch which hosts the nest. Hard, thick carton surrounds the queen cell and can continue out radially from the chamber for 2-20 cm, depending on nest size and age. Carton density decreases somewhat with distance from the queen cell, although this pattern is variable. In small, young nests the dense queen cell wall is only 1-2 cm thick. There is a rapid transition from thick queen cell carton to thin surrounding carton in such nests. Outer portions of an N. corniger nest can be relatively thin, although the termites may reinforce areas with thicker material if the nest is damaged by a predator. Older nests tend to be harder 238 Psyche [Vol. 87 Figure 2. Diagrams of a cross section through the interior of a typical A. N. corniger nest; B. N. ephratae nest. Scale = 4 cm. Black indicates open galleries, white represents carton. The queen chamber and surrounding cell is located near the center of each colony. Differences in architecture and carton density are described in the text. than younger nests (also observed by Beaumont (Dudley & Beau¬ mont 1889a)). The nest galleries are relatively small (usually ^0.7 cm in height) throughout each colony, although they sometimes increase in size near the outer edge of a nest. The layer of bumpy surface carton is attached directly to each wall of the intersecting internal galleries. The entire interior of N. corniger nests is con¬ structed of dark brown carton. The queen cell of an N. ephratae colony is also located near the center of the nest [Figure 2b, 3], but the remainder of the internal architectural design diverges from the N. corniger pattern. An N. ephratae royal chamber is surrounded by a 1.0-1.6 cm capsule of hard, dense carton. This queen cell is suspended in a matrix of thin carton composed of relatively large galleries and chambers. The transition in carton density between the queen cell and surrounding thin gallery network is abrupt. The interior carton of N. ephratae nests is a lighter brown than that of N. corniger. Except in very small N. ephratae nests (diameter <15 cm), the thin carton nest interior is encased in a 4.0-6.5 cm outer band of very hard, thick carton containing only small galleries (diameter 1980] Thome — Nasutitermes 239 ROYAL CELL SOFT CARTON, LARGE GALLERIES HARD CARTON, SMALL GALLERIES Figure 3. Photo of the interior of a small N. ephratae nest. The thin exterior envelope has been removed. sS0.5 cm). This tough layer protects the thin internal carton and is probably an excellent defensive barrier against vertebrate predators. The smooth surface covering on the outside of an N. ephratae nest encases the dense layer of carton but unlike N. corniger nests, it is not attached to the internal carton at the terminus of each gallery. Rather, the surface layer is a “superficial envelope” (Noirot 1970). This envelope is easily removed in large sections. Inspection of a piece of the envelope reveals tiny perforations over the entire surface. (Beaumont (Dudley & Beaumont 1889a) noticed small ‘apertures’ in the exterior carton of N. corniger nests.) It is possible that these holes function in air exchange and thermoregulation within the colony. The relationship between nest volume (estimated using the formu¬ la for an ellipsoid) and weight is different between N. corniger and N. ephratae (based on non-overlap of the 95% confidence limits on the slopes of the principal axes [See Figures 4 and 5] and an analysis of variance on the ratio of nest volume: weight indicating that differences between species are significant at p< 0.01). On average, N. ephratae invests less weight in carton per unit volume of nest. NEST VOLUME (cm 3 ) 240 Psyche [Vol. 87 Figure 4. The relationship between nest weight and volume in N. corniger. The equation of the first principal axis (based on correlation analysis) is given. The correlation coefficient (r) is highly significant (p < 0.001). The 95% confidence limits on the slope of the principal axis are Li = 1976.84; L 2 = 2218.26. NEST VOLUME (cm 3 ) 1980] Thorne — Nasutitermes 241 N. ephratae Figure 5. The relationship between nest weight and volume in N. ephratae. The equation of the first principal axis (based on correlation analysis) is given. The correlation coefficient (r) is highly significant (p < 0.001). The 95% confidence limits on the slope of the principal axis are Li = 2268.83; L 2 = 2965.61. 242 Psyche [Vol. 87 Conclusions Arboreal nests of the sympatric Neotropical termites N. corniger and N. ephratae are structurally consistent within species but distinctly different between species. Except in very small nests, the exterior and interior differences are reliable, useful field characters for differentiating two species that can otherwise be difficult to distinguish without alates or primary reproductives. It would be interesting to examine the nest architecture of other arboreal Nasutitermes in the New World 2 for possible phylogenetic trends. note added in proof: Chemosystematic analysis of soldier head monoterpenes and diterpenes also reveals distinctive and reproduc¬ ible differences between N. corniger and N. ephratae in most cases. However, several N. corniger nests have yielded soldiers with corniger-like monoterpenes and ephratae-like diterpenes (G. Prest- wich, B. Thorne, and B. Bentley, unpublished). Acknowledgements I thank the Smithsonian Tropical Research Institute (STRI) for generous logistical support and use of laboratory facilities. Kumar Krishna kindly identified specimens of Nasutitermes. Fellow Neo¬ tropical isopterists E.A. McMahan and G.D. Prestwich were helpful in corroborating some of the observations presented in this paper. E. McMahan, G. Prestwich, R. Silberglied, and K. Sebens assisted in editing an earlier version of the manuscript. The research was supported by a Smithsonian predoctoral fellowship (STRI) and by NSF dissertation improvement grant DEB-80-16415. References Banks, N. 1918. The termites of Panama and British Guiana. Amer. Mus. Nat. Hist. Bull. 38(17): 659-667. Becker, G. 1953. Einige Beobachtungen iiber hozzerstorende Insekten (Termiten und Kafer) in Guatemala. Zeitsch Angew Ent. 35: 339-373. 2 The exterior surfaces of N. nigriceps and N. columbicus colonies in Panama are distinct from N. corniger and N. ephratae nests (pers. obs.), but internal structure has not been investigated. 1980] Thorne — Nasutitermes 243 1961. Beobachtungen und Versuche liber den Beginn der Kolonie Entwick- lung von Nasutitermes ephratae Holmgren (Isoptera). Zeitsch Angew Ent. 49(1): 78-94. Becker, G. and K. Siefert. 1962. Ueber die chemische Zusammensetzung des Nest-und Galenematerials von Termiten. Insectes Sociaux 9(3): 273-289. Dietz, H.F. and T. E. Snyder. 1923. Biological notes on the termites of the Canal Zone and adjoining parts of the Republic of Panama. U.S. Dept. Agric. J. Agric. Res. 26(7). 279-302. Dudley, P.H. and J. Beaumont. 1889a. The termites or so-called “white ants” of the Isthmus of Panama. J. N. Y. Microscop. Soc. 5: 59-70 and 111-112. 1889b. Observations on the termites or white ants of the Isthmus of Panama. Trans. N.Y. Acad. Sci. 8: 85-114. Emerson, A.E. 1925. The termites of Kartabo, Bartica District, British Guiana. Zoologica 6(4): 291-459. 1938. Termite nests—a study of the phylogeny of behaviour. Ecol. Monogr. 8: 247-284. Holmgren, N. 1910. Versuch einer Monographic der amerkanischen Eutermes— Arten. Mit- tenlungen Naturhistorischen Museum Hamburg, vol. 27, Jahrbuch der Hamburgischen Wissenschaftlichen Anstalten, Beiheft 2: 171-325. Mathews, A.G.A. 1977. Studies on Termites from the Matto Grosso State, Brazil. Edited by Academia Brasileira de Ciencias, Rio de Janeiro, R.J- Motschulsky, V. 1855. Etudes Entomologiques, N. 4, p. 10. Noirot, C. 1970. The nests of termites. In: Biology of Termites (K. Krishna and F.M. Weesner, eds.) Vol. 2 pp. 73-125. Academic Press, N.Y. Snyder, T.E. . 1925. New American termites, including a new subgenus. J. Wash. Acad. Sci. 15(7): 152-162. 1926. Termites collected on the Mulford Biological Exploration to the Ama¬ zon Basin, 1921-2. Proc. U.S. Nat. Mus. 68: 1-76. 1949. Catalog of the Termites (Isoptera) of the World. Smithsonian Miscella¬ neous Collections 112: 1-490. Smithsonian Institution, Washington, 1959. New termites from Venezuela, with keys and a list of the described Venezuelan species. Am. Midland Nat. 61(2): 313-321. Snyder, T.E. and J. Zetek. 1924. Damage by termites in the Canal Zone and Panama and how to prevent it. U.S. Dept. Agric. Bull. 1232. 26 pp. SYNONYMY OF ARCHISOLVA ENDERLEIN AND ITS PLACEMENT IN THE STRATIOMYIDAE (DIPTERA)* By Norman E. Woodley Museum of Comparative Zoology Harvard University Cambridge, Massachusetts 02138 Enderlein (1921) described the genus Archisolva from a unique female specimen of a new species described concurrently, A. carinifrons. It was placed in the subfamily Xylophaginae, tribe Metoponiini. In the former category, Enderlein assembled diverse taxa presently considered to belong to several families of Diptera Brachycera. The Metoponiini contained stratiomyids included in two subfamilies in present classifications, the Chiromyzinae and Beridinae, which Enderlein grouped together because they lack scutellar spines. Archisolva has remained enigmatic to subsequent workers largely due to the lack of additional material. James (1975) was not able to place the genus in any subfamily as presently defined, on the basis of the description, and relegated it to an “unplaced genus and species of Stratiomyidae. I have recently examined Enderlein’s type specimen, and have been able to properly place the taxon. The genus Archisolva is congeneric with Salduha Walker (1859; new synonymy), a genus in the Pachygasterinae. Three characters that the type specimen shares with Salduba, which appear to be autapomorphic for the genus and are shared by all members of the genus I have examined, are: (1) the median, longitudinal frontal carina found in females; (2) the strongly clavate hind femora (Fig. 1); and (3) the elongate, narrow wings (Fig. 2; see also Enderlein’s Fig. 8, p. 187). The frontal carina may be faint in some species of Salduba, but at least a trace of it is present in all the females examined. In the holotype of A. carinifrons, which has the strongest frontal carina of any species I examined, this feature may be artificially exaggerated. The uneven drying of the eye surfaces indicates that the specimen was slightly teneral, and the lateral areas of the frons may be collapsed more than would normally be •Manuscript received by the editor March 22, 1981 245 246 Psyche [Vol. 87 Figs. 1-2. Salduba carinifrons (Enderlein). 1. Left hind femur, showing ventral tubercles. 2. Right wing. Figures are from the holotype specimen. expected. The elongation of the wing is especially evident basal to the discal cell. The alula is very narrow and the anal angle is very broadly rounded, the region posterior to the anal cell being no wider than the cell itself. The type specimen of Archisolva carinifrons shares the following characters with members of Salduba which are useful in identifying the genus (these characters cannot be considered autapomorphic for Salduba because they are present in other pachygasterine taxa): (1) antennal flagellomeres one to seven forming an elongate but compressed complex 2.5 to 3.5 times longer than wide; (2) eighth flagellomere forming a long, plumose style much longer than the rest of the flagellum; (3) second antennal segment produced inter¬ nally along the flagellum; (4) scutellum unarmed; (5) wing with R 2 +3 proximal to r-m; and (6) abdomen much longer than wide. It should be noted that Enderlein’s figure of the antenna of Archisolva carinifrons (1921: 187, Fig. 7) shows its general form, but the majority of the eighth flagellomere is missing, and the angle at which he illustrated the antenna does not show the projection of the second segment along the flagellum. Salduba has previously been unrecorded from the Oriental Region. Previous material has been collected mainly from New 1980] Woodley — Synonymy of Archisolva 247 Guinea, and no species has been described from outside the Australian Region. Thus the present new generic synonymy results in the first report of Salduba from the Oriental Region. Salduba carinifrons (Enderlein), new combination Archisolva carinifrons Enderlein, 1921: 187. Type material. The unique female holotype is presently housed in the Zoologisches Museum of the Humboldt-Universitat, Berlin, East Germany. It is labeled “Lombok Sapit 2000' Mai-Juni 1896. H. Fruhstorfer/ Type [red]/ Archisolva carinifrons Type Enderl. 9 Dr. Enderlein det. 1920.” I have added a determination label indicating the new combination. The specimen is missing the last two segments of the right antenna. The left antenna is missing most of the eighth flagellomere, and is glued to a paper point beneath the specimen. The left middle leg beyond the middle of the femur, and the left wing are also lost. The right wing is glued to a paper card beneath the specimen. Remarks. At present it is not possible to determine if S. carini¬ frons is conspecific with any other species of Salduba without examination of other types. The genus at present is in need of revision. Salduba carinifrons has the ventral spine-like tubercles on the hind femora (Fig. 1) that some, but not all, Salduba species possess. This character would appear to be apomorphic for the group of species that exhibit the tubercles, as no other pachygasterines that I am aware of possess them. Some species of Salduba do not have femoral tubercles, but it cannot be determined at present if this character state is plesiomorphic or has resulted from a secondary loss of the tubercles. The same argument can be applied to the posterodorsal swelling on the fifth abdominal tergite that some Salduba possess. Although quite faint in S’, carinifrons, it is present. Of the species I have examined, S. carinifrons appears to be most closely related to specimens identified as S. lugubris Walker. The two taxa share the above pair of characters, and also lack thoracic vittae and frontal processes at the bases of the antennae. These two species have the narrowest wing bases that I have observed within the genus. Salduba carinifrons differs from all other species I have seen in that it has wholly pale anterior tibiae. Acknowledgments. I am grateful to H. Schumann for the loan of 248 Psyche [Vol. 87 the Enderlein type, W. J. Turner for the loan of Salduba material from the James Entomological Collection at Washington State University, and R. J. McGinley for reviewing the manuscript. Literature Cited Enderlein, G. 1921. Uber die phyletisch alteren Stratiomyiiden-subfamilien (Xylophaginae, Chiromyzinae, Solvinae, Beridinae, und Coenomyiinae). Mitt. Zool. Mus. Berlin 10: 151-214. James, M. T. 1975. Family Stratiomyidae, in M. D. Delfrnado and D. E. Hardy, eds. A Catalog of the Diptera of the Oriental Region. Volume II. Suborder Brachycera through division Aschiza, suborder Cyclorrapha. Honolulu, University Press of Hawaii. 459 pp. Walker, F. 1859. Catalogue of the dipterous insects collected in the Aru Islands by Mr. A. R. Wallace, with descriptions of new species. Proc. Linn. Soc. London 3: 77-131. OBSERVATIONS ON THE PROVISIONING BEHAVIOR OF AMMOPHILA ABERTI HALDEMAN (HYMENOPTERA: SPHECIDAE) By F. D. Parker, V. J. Tepedino, and D. L. Vincent* Bee Biology & Systematics Laboratory Agricultural Research Science & Education Admin., USDA Utah State University, UMC 53 Logan, Utah 84322 Introduction Nest-building aculeate Hymenoptera construct a variable number of cells within each nest; a single egg is laid in each cell by the nesting female who also supplies sufficient food for the development of her offspring. The sequence of oviposition and food provisioning may vary from oviposition followed by prey stocking (e.g., Odynerus ), to oviposition on the initial prey item followed by additional provision¬ ing (e.g., Ammophila ), to oviposition after all food has been stocked (most bees). The manner of provisioning is also quite variable in those species that supply the offspring with more than one prey item. Evans (1966) delimited three basic types of provisioning behavior which are thought to form an evolutionary sequence: 1) mass provisioning, in which prey are brought to the cell in rapid succession and the cell is completed before eclosion of the egg; 2) delayed provisioning, in which prey are sometimes stocked over a longer period of time due to environmental circumstances, and egg eclosion occasionally occurs before provisioning is completed; and 3) progressive provisioning, in which prey are provided over an extended period of time, and the offspring pass through several larval instars before the final prey item is presented and the cell sealed. Evans (1966) further subdivided progressive provisioning into two additional categories but noted that this distinction was not clear-cut. For our purposes it is sufficient to treat progressive provisioning as a single category. Progressive provisioning is thought to reduce offspring mortality caused by parasites and predators, because the adult female is able to spend ♦Present address: USDA-SEA, AR, Beneficial Insect Introduction Laboratory, Building 417, BARC-East, Beltsville, Maryland 20705 Manuscript received by the editor January 8. 1981. 249 250 [Vol. 87 Psyt more time guarding her nest (Evans 1966). In addition, Malyshev (1968) suggested that prey items are fresher and less likely to be unsuitable to offspring when supplied progressively. The genus Ammophila is interesting because it encompasses the evolutionary transition from oviposition upon a single prey to progressive provisioning (Evans 1959, Powell 1964). Studies of representative species can clarify the successive steps in the evolution of a more complex behavior, i.e., progressive provisioning, from its simpler antecedents. Here we report on the method of provisioning followed by Ammophila aberti Haldeman, a species suspected of practicing delayed or progressive provisioning (Hicks 1932, Evans 1959, Powell 1964). In addition, we provide data on prey records, egg placement, and report observations that suggest facultative clepto- parasitism. Study Site and Methods A small nesting population of A. aberti (12 females) was observed at Greenville Farm (GF), an agricultural experiment station operated by Utah State University in North Logan, Cache County, Utah. In contrast to a report by Hicks (1932) that A. aberti is bivoltine at Boulder, Colorado, this species is univoltine in northern Utah and flies from the first half of July to late August. Our observations were made on three consecutive days beginning 23 July and then sporadically through 4 August. The wasps nested in three bare, moist 6m 2 soil beds that were prepared and maintained for a population of alkali bees ( Nomia melanderi Cockerell; Bohart 1972). The beds were surrounded by experimental plantings of alfalfa, sugarbeets, wheat, and vegetable crops. Wasps were marked with acrylic paints on various parts of the body, and their nests were marked with similarly painted toothpicks. We also applied dots of paint to the plugs of closed nests to determine if nests were visited during our absence. Nests at GF could not be excavated without disturbing both the wasps and alkali bees that used the beds. Instead, we excavated nests of A. aberti from a large population that nested in a 1 ha alkali flat at Cornish, Utah, 40 km northwest of GF. Soil at Cornish was mostly bare with some patches of pickleweed ( Allenrolfea occidentalis (S. Wats.) Kuntze) and moist because of seepage from a nearby irrigation ditch. An alfafa field b&rdered the nesting site on one side and halophytic shrubs (e.g., Sarcobatus, Cercocarpus, Atriplex) on 1980] Parker, Tepedino, & Vincent — Ammophila 251 the other sides. Nests were excavated immediately after their completion. All prey items were collected for subsequent identifi¬ cation. Results Nesting activity —Nesting activity varied greatly among female wasps. During the first week of observation at GF, four marked females did not nest at all. Although they were frequently seen flying around the beds and investigating the soil surface, they were absent for long periods of time and may have nested in other areas. Those wasps that did dig in the beds also showed considerable variability in their nesting activity: two females began five nests each; two others began eight nests each; and the remaining four began 1, 3, 4, and 12, respectively. Many of the nests that were initiated were terminated prematurely, before provisioning began. We observed complete provisioning and nest closure for only 10 (22%) of the 46 nests begun by the eight females. Because of our occasional absences from the nesting site, we probably missed the provisioning and completion of some other nests; but we are convinced that many of the nests were abandoned prior to provisioning. On numerous occasions, females dug nests, plugged them, and never subsequently disturbed the paint marks on the plugs. All abandoned nests were plugged with pebbles and soil. Hicks (1932) and Powell (1964) also noted that female A. aberti sometimes abandoned nests, and Brockmann and Dawkins (1979) recently reported high percentages of nest abandonment by Sphex ichneumoneus L., another ground-nesting sphecid wasp. Abandoned nests were frequently reinspected briefly by their builders. Inspection occurred at least once per day, usually for two or three days subsequent to abandonment, and was restricted to examination of the closing plug. In only four cases was an abandoned nest reopened, and three of these reopenings were by one wasp. Silver, whose behavior was also atypical in other respects (see below). Provisioning— The suggestion that A. aberti practices delayed or progressive provisioning is based upon limited observations and a few nest excavations: Hicks (1932) noted that some females took up to seven days to provision their nests (he also notes that others provisioned rapidly) and that the larva is sometimes large “before the final victim has been placed before it”; Evans’ (1959) excavations of two nests plus observations that one female took at least two (and 252 Psyche [Vol. 87 probably three-to-four) days to provision one nest; Powell’s (1964) excavations of five nests. Two lines of evidence suggest that A. aberti does not practice delayed or progressive provisioning in northern Utah. First, prey¬ collecting trips at GF were generally rapid (x= 45.8 min, ±35.0, range 10-168 min) and at least two prey (and usually more) were collected in succession. We have data for five nests from the initiation of digging through provisioning and final nest closure: two nests took more than one day from initiation to completion (40, 48 hrs), but both were constructed and provisioned during a period that included a day of rain when neither female was active; the other three nests required an average of 24 hrs (21, 24, 27 hrs) for completion. Thus, nests typically were not provisioned over an extended period of time as would be the case if progressive provisioning were practiced. The second line of evidence against progressive provisioning comes from the nest excavations at the Cornish site. Nests were excavated immediately after final closure: if progressive provisioning was practiced, most nests should have contained either third or fourth instar wasp larvae or an unhatched egg with one or two prey. This was not the case. Of 50 nests excavated, 30 contained unhatched eggs attached to larval prey, two contained eggs that had just hatched that day, 12 had young (first or second instar) larvae, and only one each had medium (third instar) or large (fourth instar) larvae. Four nests had prey but no egg. Cells averaged about six prey per cell (Table 1). Prey records —Fourteen genera of prey in five families of Lepi- doptera were recorded from the 50 nests excavated at Cornish (Table 1). This contrasts with previous reports that A. aberti provisions its nests exclusively with geometrids (Hicks 1932, Evans 1959, Powell 1964; Evans reported finding a few hesperiids also). Members of the family Pieridae were the most abundant prey items; 52.5% of all prey were pierids and at least one pierid larva occurred in 74.0% of the nests. Noctuids were also well represented and accounted for 32.4% of all prey individuals and were found in 38.0% of all nests. The most abundant genera of prey were Colias eury theme (Pieridae), a species near Drasteria sp. (Noctuidae), and Pier is (both rapae (L.) and protodice Boisduval & LeConte). Most nests contained a single species of prey (68.0%); 20% of all nests contained two species and 12% contained three species of prey. Thus, A. aberti, is not restricted to geometrids as prey items and a substantial number of nests (32.0%) are provisioned with two or more prey species. 1980] Parker, Tepedino, & Vincent — Ammophila 253 Table 1. Prey records from 50 Cornish nests. Total number of nests exceeds 50 because more than one taxa frequently occur in same nest. Taxa Total Larvae Nests Percent Larvae Total Nests Geometridae Nr. Anacamptodes 19 3 6.7 6.0 Nr. Caripeta #2 15 3 5.3 6.0 Nr. Semiothisa 4 1 1.4 2.0 Geometrid #2 2 1 0.7 2.0 Total 40 7 14.1 14.0 Hesperiidae Pyrgus communis (Grote) 1 1 0.4 2.0 Pholisora catullus (F.) 1 1 0.4 2.0 2 2 0.7 4.0 Noctuidae Nr. Drasteria 80 16 28.2 32.0 Nr. Toxocampa 1 1 0.4 2.0 Nr. Acontia 5 1 1.8 2.0 Ogdoconla cinereola (Guenee) 2 1 0.7 2.0 Amphipyrinae 4 1 1.4 2.0 92 19 32.4 38.0 Peridae Pier is spp. 38 10 13.4 20.0 Colias eurytheme (Boisduval) 111 30 39.1 60.0 149 37 52.5 74.0 Pyralidae Loxostege sticticalis L. 1 1 0.4 2.0 1 1 0.4 2.0 Egg placement —We recorded the area of egg placement on the prey larvae for 28 of the 31 unhatched eggs excavated from nests at Cornish. Four eggs were placed on the thorax (two between the first and second segments and one each on the first prothoracic segment and between the first and second segments); 24 eggs were placed on the abdomen (seven each on the first and second segments, two on the third segment, three on the fourth segment, and five on the first proleg; two eggs were laid in one cell). Cleptoparasitism and prey stealing —In some species of aculeate Hymenoptera, females no longer build nests or forage for food for their offspring. Instead, the nests of females of other species are located and the food stored by these hosts is utilized to rear the 254 Psyche [Vol. 87 offspring of the cleptoparasite (Wheeler 1919, Evans 1966, Bohart 1970, Eickwort 1975). Facultative cleptoparasitism, in which females occasionally usurp the nests of conspecifics rather that females of other species, is thought to be the initial step in the evolution of obligate cleptoparasitism. Examples of facultative parasitism have been reported for several species (Alcock 1975, Eickwort 1975) but not for A. aberti. During our observations at GF, one female. Silver, exhibited cleptoparasitic behavior. At 1250 hrs on 23 July, she opened a nest that was being provisioned by another female, Yellow Legs, while the latter was out foraging, removed a single larva, stung it several times, dropped it outside the nest entrance, and re-entered the nest. At this point the nest owner returned, forcibly evicted Silver and soon permanently sealed the nest; the larva removed by Silver was left outside the nest. Curiously, immediately after the nest was perma¬ nently sealed, Silver returned and performed a similar sequence of sealing behaviors. Soon after this sequence was completed, Silver located another nest that had just been finished by White. Silver opened this nest, removed four larvae, one at a time, and deposited them adjacent to the burrow entrance (Fig. 1). At this point. White returned and Silver was again forcibly evicted, and the burrow then sealed by White without returning the larvae to the nest (Fig. 2). As soon as White had departed, Silver returned, reopened the nest, and removed two more prey. Silver then grasped each larva in turn, flew off a distance of about 3 m, landed either on the ground or a fence post (Fig. 3), stung the prey, and then returned to White’s burrow and took the larva inside (Fig. 4). After all six larvae were treated in this manner, the nest was sealed and never reopened. It is possible that the egg originally deposited by White was dislodged during this sequence, although we have no evidence of this, nor do we know if Silver ever deposited an egg of her own. Prey stealing was observed on several occasions during our excavations at the Cornish site. In several instances, prey-laden females were attacked as they returned to their nests from foraging trips. Typically, several other females would pounce upon the prey- owner; in the ensuing struggle, one of the attackers would fly off with the prey which was dropped as the female attempted to defend herself. The stolen prey was typically carried off for several meters, 1980 ] Parker, Tepedino, & Vincent — Ammophila 255 Figures 1-4. Fig. 1. Silver removing prey from White’s nest after opening it. Fig. 2. White begins to replug the burrow after evicting Silver. Note that prey have not been returned to the nest. Fig. 3. Silver stings one of the prey which she has carried to a nearby fence post. Fig. 4. Silver returning the last of the prey to White’s nest. stung, and then carried into the thiefs burrow. Victimized females usually flew off after escaping their attackers. Because females were unmarked, it was not clear if the same wasps did all or most of the attacking or if the attackers ever foraged for prey in the field. Discussion Evans (1959) classified A. aberti as a delayed (rarely mass) provisioning species. Powell (1964) agreed but also suggested that progressive provisioning might occur. In contrast, our observations and nest excavations strongly suggest that A. aberti is primarily a mass provisioning species, at least in northern Utah. At the Cornish site, only two of 46 nests excavated immediately after completion contained larvae that were beyond the second instar while 30 nests contained eggs that had not yet hatched. In addition, observations at GF showed that wasps rapidly completed digging and provisioning their nests and did not reopen them after completion. Nevertheless, 14 nests (30.4%) did contain first or second instar larvae when excavated, and these nests do fit Evans (1966) definition 256 Psyche [Vol. 87 of delayed provisioning. Any of several possibilities might explain this relatively high incidence of “delayed” provisioning. The first is that the population is behaviorally polymorphic for the provisioning trait(s), i.e., that both mass and delayed provisioning behaviors currently exist. A second possible explanation is inter-individual variability in the speed with which prey can be found, subdued, and returned to the nest. Nests that appear to have been provisioned on a delayed basis may simply be the work of individuals that are less efficient at hunting than others. Our data are not detailed enough to allow additional discussion of these possibilities. A third (and more likely) explanation is that A. aberti is a mass provisioning species but that the rate of provisioning is influenced by environmental circumstance. As Evans (1966) points out, the dis¬ tinction between mass and delayed provisioning is a tenuous one. Indeed, if provisioning is delayed merely because of inclement weather (as were two nests at GF) or temporary paucity of prey as Evans (1966) suggests, then any distinction between mass and delayed provisioning is artificial. Proof of delayed provisioning requires that the insect delay its pace of provisioning even when prey are abundant and weather conducive to flight, and A. aberti does not appear to do this in any consistent way. Hicks (1932) also reported that nests were sometimes completed rapidly and at other times slowly but offered no explanation for these differences. It is not clear why females abandon so many nests. Brockmann & Dawkins (1979) found that many of the nests abandoned by the female Sphex ichneumoneus were later used by other females, and they concluded that if abandonment was due to unsatisfactory substrate or nest location, these conditions must have been tem¬ porary. In the small population we studied, abandoned nests were not re-used later. Tsuneki (1963) and Evans (1966) have suggested that the “false” burrows constructed adjacent to the main nest entrance by several digger wasp species may serve to decoy parasites. Con¬ ceivably, abandoned nests could serve the same purpose but as Brockmann and Dawkins (1979) have pointed out, decoys would have to benefit the females that dug them more than other unrelated members of the population. This might be the case if females tended to cluster their nests within a relatively restricted area. Then enemies that invaded abandoned unrewarding nests might be discouraged from additional searching in the immediate area (Tepedino et al. 1980] Parker, Tepedino, & Vincent — Ammophila 257 1979). Some female A. aberti did construct all their nests, both abandoned and completed, in the same area of one of the beds. For example. Yellow Legs clustered all twelve of her nests in bed 1, while White Thorax split her eight nests between local areas in beds 1 and 2. Silver was, again, atypical; she divided her eight nests almost equally among three beds. Thus, in some cases abandoned nests may be of use in deterring enemies, but this suggestion requires further study. Equally perplexing was the reinspection of nests for several days after they had been completed or abandoned. Reinspection cannot be explained as a result of conditioning to return to the new nest byway of the older ones, because it did not occur on every return trip to the new nest. One possibility is that females inspect older nests externally as a means of assessing the incidence of disturbance, i.e., enemies in the area, and then use this information to “decide” whether or not to move to other nesting areas. Acknowledgements We are indebted to D. M. Weisman, Systematic Entomology Laboratory, USDA, for all prey identifications and to Howard Evans and Arnold Menke for helpful comments on the manuscript. Literature Cited Alcock, J. 1975. Social interactions in the solitary wasp Cerceris simplex (Hymenoptera: Sphecidae). Behavior, 54: 142-152. Bohart, G. E. 1972. Management of wild bees for the pollination of crops. Annu. Rev. Entomol., 17: 287-312. 1970. The Evolution of Parasitism Among Bees. Logan, Utah: Utah State Univ., 30 pp. Brockmann, H. J. and R. Dawkins 1979. Joint nesting in a digger wasp as an evolutionarily stable preadaptation to social life. Behavior, 71: 203-245. Eickwort, G. C. 1975. Gregarious nesting of the mason bee Hoplitis anthocopoides and the evolution of parasitism and sociality among megachilid bees. Evolution, 29: 142-150. Evans, H. E. 1966. The Comparative Ethology and Evolution of the Sand Wasps. Cam¬ bridge, Mass.: Harvard Univ. Press. 526 pp. 1959. Observations on the nesting behavior of digger wasps of the genus Ammophila. Amer. Mid. Natur.. 62: 449-473. 258 Psyche [Vol. 87 Hicks, C. H. 1932. Notes on Sphex aberli (Hald.). Can. Entomol., 64: 145-151. Malyshev, S. I. 1968. Genesis of the Hymenoptera and the Phases of Their Evolution. London: Methuen. 319 pp. Powell, J. A. 1964. Additions to the knowledge of the nesting behavior of North American Ammophila (Hymenoptera: Sphecidae). J. Kans. Entomol. Soc., 37: 240-258. Tepedino, V. J., L. L. McDonald and R. Rothwell. 1979. Defense against parasitization in mud-nesting Hymenoptera: Can empty cells increase net reproductive output? Behav. Ecol. Sociobiol., 6:99-104. Tsuneki. K. 1963. Comparative studies on the nesting biology of the genus Sphex (s.l.) in east Asia (Hymenoptera: Sphecidae). Mem. Fac. Liberal Arts, Fukui Univ., 13: 13-78. Wheeler, W. M. 1919. The parasitic Aculeata, a study in evolution. Proc. Amer. Philo. Soc., 58: 1-40. REVIEW OF THE CONIOPTERYGIDAE (NEUROPTERA) OF NORTH AMERICA WITH A REVISION OF THE GENUS ALEUROPTERYX ' By Victor Johnson * 2 Introduction and Review of Literature The smallest members of the Neuroptera belong to the family Coniopterygidae, which has several characteristics unusual within the order. The wings have reduced venation with few cross-veins and without the terminal branching of longitudinal veins found in other families. Coniopterygids produce a characteristic waxy secre¬ tion from wax glands on the head, thorax and abdomen which gives them their common name “dusty-wings”; no other neuropterans produce wax. Another unusual feature is the presence of a scler- otized penis in several genera and species. The only other neurop¬ terans with a sclerotized penis are some species of Mantispidae (Tjeder 1956). The first major U.S. work on this group was a Nearctic revision by Banks (1906) who reported seven U.S. species and provided a key to genera based on wing venation. Because wing venation is not always bilaterally symmetrical, a single specimen may key out to different genera depending upon the wing used. The family re¬ mained in a state of confusion until Meinander (1972) published his world revision, in which he described 22 new species from North America. He described an additional nine species in 1974 and four more in 1975. Henry (1974) recorded the introduction and establish¬ ment of Aleuropteryx juniperi Ohm from Europe into the eastern part of the United States. Johnson (1976) described the genus ‘This paper (No. 80-7-205) is published with the approval of the Director of the Kentucky Agricultural Experiment Station and is based on research performed in partial fulfillment of the requirements for the Ph.D. degree in Entomology. 2 Former research associate in the Department of Entomology, University of Kentucky, Lexington, Kentucky 40546. Present address: USDA-APHIS-PPQ, Box 182729, Erlanger, Kentucky 41018. To simplify information in this publication, trade names of some products are used. No endorsement is intended, nor is criticism implied of similar products not named. Manuscript received by the editor February 2, 1981. 259 260 Psyche [Vol. 87 Bidesmida with one species ( B. morrisoni ) bringing the total to 40 species in 8 genera. This present study describes 5 additional new species. There is little doubt that there are many more undescribed species in North America. Coniopterygids have been considered rare by most entomologists, mainly because of their small size, inconspicuous appearance and superficial resemblance to Psocoptera and Aleyrodidae. In addition, Withycombe (1922) stated that only the males are attracted to incandescent lights. I have found males and females only rarely attracted to incandescent lights, but both sexes are readily attracted to blacklights and the use of blacklight traps is the most efficient method of collecting adults. Rather than being rare, many coniopterygids are quite common. Several species can be easily collected in numbers in the southern part of the United States where they appear to be widely and uniformly distributed. I have noted large numbers of Semidalis vicina (Hagen) congregating on oak and maple shrubbery in Kentucky, Tennessee and Arkansas and have seen this species and several others in large numbers in Texas feeding on an unidentified aphid on hackberry. Withycombe (1923) considered several coniop¬ terygids to be “exceedingly common, at least in England. ..”. He found Conwentzia sp. to be one of the “commonest insects in London parks” on Quercus and Platanus with Semidalis sp. and Coniopteryx sp. frequently plentiful. The life histories of very few of the Coniopterygidae are known. Withycombe (1923) made a major contribution with studies of several species in England, Muma (1967) studied 5 . vicina in Florida and Henry (1976) reported on A. juniperi in Pennsylvania. Other studies have been made but these frequently include ambiguous species identification. Both larvae and adults of coniopterygids are predaceous and several have been studied as biological control agents. Muma (1967) evaluated S. vicina for control of mites on citrus. He found this species to have several characteristics which made it suitable for biological control of citrus pests: wide distribution, stable mean population and wide food tolerance range, including rust mites, spider mites, whiteflies and scale insects. Individuals were found to consume 29-83 citrus red mites (eggs, larvae, and pupae) per day of development. Quayle (1912) reported Conwentzia hageni Banks (Conwentzia California Meinander) to be one of the commonest 1980] Johnson — Review of Coniopterygidae 261 enemies of spider mites in Southern California citrus, consuming 6-15 mites per day of development. Collyer (1951) reported C. pineticola Enderlein to consume 15-40 mites per day. Arrow (1917) found Conwentzia psociformis Curtis to feed on Phylloxera sp. on oak, attacking all stages with “great voracity”. Withycombe (1924) found that the main check on populations of Phylloxera punctata Light in England was C. psociformis. Henry (1976) stated that A. juniperi preys on two species of scale insects: juniper scale, Caru- laspis juniperi (Bouche) and the minute cypress scale, Carulaspis minima (Targioni-Tozetti). Ward (1970) also reported this species feeding on C. juniperi in Great Britain. In addition to feeding on live prey, adults have been reported to feed on other substances such as honeydew (Withycombe 1923 and Arrow 1917), scale secretions and honey water (Henry 1976). Several parasites are reported for coniopterygids. Withycombe (1923) reported two species of Hymenoptera to parasitize cocoons of C. psociformis in Great Britain; the female of Lygocera sp. tears a small hole in the cocoons for insertion of the parasite’s eggs. The parasite larvae feed on the coniopterygid pupa, then pupate and emerge from the host cocoon the following summer. Ceraphron sp. have been found to emerge from coniopterygid cocoons during July and August. Muma (1967) reported three parasites of the pupae of C. vicina: Dendrocerus conwentziae Gah., Camptoptera sp. and Cosmoccidea morilli How. In view of their predaceous habits and potential for biological control of mites and small insects, there is a need for biological information on this group. Life histories are known for very few species and few species have correlation between males and females and between larvae and adults. This present study was undertaken to advance the taxonomic status of this very interesting group so that life history investigations might be more easily completed. Materials and Methods All specimens were examined either in glycerol or ethyl alcohol. Specimens on pins or points were treated with household cleaner, Formula 409®, for 2-24 hours, washed in water and then placed in glycerol. The Formula 409 softened the specimens and many times returned them to a state indistinguishable from specimens which have been stored in alcohol. 262 Psyche [Vol. 87 For examination of genitalia, either the terminal abdominal segments or the entire abdomen was removed and treated with 10% KOH at room temperature for 2-10 hr. In some cases, specimens were placed in a cleaning sonicator for a few seconds, but this was too severe a treatment for general use. Specimens were then washed with water and placed in glycerol. A dissecting microscope at 95X magnification was used for determination and for illustrations. A Zeiss Photomicroscope II® was used for more detailed examination at magnifications up to 400X. Illustrations were prepared freehand with the use of a counting grid mounted in one ocular of the dissecting microscope. Measure¬ ments are accurate to .04 mm. Illustrations are accurate to .02 mm. After examination and illustration, all specimens which had been dissected for examination of genitalia and all specimens which were fragile and/ or broken were placed in glycerol in genitalia vials for permanent storage. All other specimens were placed in vials of 80% ethyl alcohol with a few drops of glycerine. Specimens used in this study were from the collection of the author (AUTH) or borrowed from one of the following collections: Arizona State University (ARIZ), Illinois Natural History Survey (INHS) or Utah State University (UTAH). Types were deposited in one or more of these collections or in the National Museum of Natural History (USNM). Meinander (1972) types are deposited in the California Academy of Sciences (CAS), University of California at Berkeley (UCA) or the National Museum of Natural History. Classifications and Descriptions Due to the recent world revision by Meinander (1972), some material which is readily available in that revision was omitted from this study. Synonomies were limited to original descriptions and to publications after 1972. In the interest of standardization, I have followed Meinander’s format regarding descriptions and illustra¬ tions and have used the same terminology where possible. I have noted my differences in interpretation from Meinander. I have prepared illustrations of previously undescribed species and other species where necessary. The descriptions include only those characters which have been found to vary within the genus. Keys are provided to the species. 1980] Johnson — Review of Coniopterygidae 263 Species are discussed in alphabetical order. Under the heading, new material examined, new country and state records are indicated by an asterisk. CONIOPTERYGIDAE Burmeister, 1839 Coniopterygidae Burmeister, 1838:771. Type: Coniopteryx Curtis, 1834. Eggs: Light colored, ovoid with micropylar end pointed and chorion reticulated. Incubation period varies with temperature. Withycombe (1924) reported 6-21 days for incubation. Larvae: Spindle-shaped, generally smooth, except for rows of small setae on each abdominal segment. Head small, rounded, prognathous; slightly retracted into thorax. Eyes formed of 4-5 facets. Antennae 2 segmented. Labrum projecting, covering the mandibles completely in Coniopteryginae and partially in Aleurop- teryginae. Mandibles enlarged basally, sharply pointed, slightly grooved ventrally. Maxillae pointed, with external barbs. No maxillary palpi present. Labrium reduced. Thorax large, soft, sharply marked off from abdomen. Three segments subequal. Legs well developed, long; tarsi one segmented with two simple claws and a well developed empodium. Tibia and tarsi not freely articulating. Abdomen 10-segmented, tapering, with 10th segment adhesive. Notes: Meinander (1972) reported the labial palpi to be 2 segmented but Withycombe (1923) reported a pair of three seg¬ mented labial palpi. The larval stages require about 2-4 wk for development. Withy¬ combe (1923), working with several species, and Henry (1976) working with A. juniperi, reported three larval instars, while Muma (1967) working with S. vicina and Quayle (1912) working with C. hageni reported 4 larval instars. Meinander (1972) considers the family to have 3 larval instars. I have found 3 species in 2 genera of the Coniopteryginae to have 4 larval instars. Prior to pupation, the larvae build a flat, ovoid cocoon composed of an inner and an outer layer of white silk. The silk is produced by modified malpighian tubules (Meinander 1972) connected to an eversible anal papilla (Withycombe 1924). The cocoon is similar to that produced by some spiders and the emerging adult coniopterygids have been mistakenly thought to be parasites of spiders. Withycombe (1923) stated that 264 Psyche [Vol. 87 there are 2 types of development in Conwentzia in England. During the early and mid-summer, pupation takes place normally and within about 2 weeks the adults emerge; in late summer, the larvae do not pupate immediately, but overwinter as prepupae in the cocoon and pupate early in the following spring. Henry (1976) reported A. juniperi in Pennsylvania overwintering as 2nd instar larvae and to be active during warm periods during the winter. Pupa: Quadrate, short with the head bent forward at an angle to thorax. Notes: Just prior to emergence, a hole is cut in the cocoon through which the adult subsequently emerges. The pupal skin is either left entirely or partially within the cocoon or the pupa emerges and then sheds the pupal skin. Adults: Hypognathous, strongly sclerotized head capsule. Ocelli absent, compound eyes well developed and large. Antennal sclerite and antennal condyle small. Antennal sockets often with unscler- otized area of frons between them. Male antennal segments modified and broader than in females. Mandibles small; maxillae well developed with 5-segmented palpi; labium well developed with 3- segmented palpi. Prothorax short and lightly sclerotized; meso- and metathorax well developed, strongly sclerotized, with mesothorax being larger. Meso- and metathorax of some species with distinct lateral shoulder spots darker than surrounding areas. Legs slender with 5-segmented tarsi, 4th segment flattened. Males with clasping setae on anterior femur. Most with 2 pairs of well-developed wings. Exceptions are some species of Helicoconis and Coniopteryx and most species of Con¬ wentzia which have reduced metathoracic wings. Wings held roof¬ like over body. Venation of fore wing: Costa (C) much reduced and visible only at base. Subcosta (Sc) runs parallel with margin and is distally furcate; posterior branch resembles a cross-vein (Withycombe 1922). Radius (R) in most species basally apparently crossing base of medius (M), but no actual crossing occurs. Radial sector (Rs) branches off in middle of wing. Media forked except in Conio- compsa. Basal cross-vein may be present along with radio-medial cross-vein (Aleuropteryginae have 2 radio-medial cross-veins). Cubitus (Cu) forks near base into 2 branches. One medio-cubital cross-vein present, striking M on stem or posterior branch. Two 1980] Johnson — Review of Coniopterygidae 265 anal veins. Costal area with 2 or fewer cross-veins. Two basal cross¬ veins present between Cu 2 and Ai. Venation of hind wing: Costa and subcosta similar to fore wing. Rs forks off near base in Aleropteryginae, more distally in Coniop- teryginae; generally furcate. Radial cross-vein between Ri and Rs, strikes either stem of Rs or its anterior branch. M forked except in Coniopteryx and some Coniocompsa. A radio-medial cross-vein present, striking anterior branch of M except in Coniopteryx, where M is unforked. Cu forked near base. Two anal veins present. Two or fewer cross-veins in basal part of costal area. Membrane of wings mostly clear or unicolorous, but some with markings. Marginal fringes usually present and short. Frequently a group of hairs along base of posterior margin of hind wing and along base of costa of hind wing. Abdomen weakly sclerotized except for genitalia. Segments 1-8 of Aleuropteryginae and segments 1-7 of Coniopteryginae with spiracles. Lateral and dorsal wax glands form transverse bands. Aleuropteryginae with paired organs called plicaturae on some segments; function unknown. Notes: Newly emerged adults are pale and do not have the characteristic waxy power on the body and wings. Within a short time, the wax is secreted in long spirals from the wax glands, primarily located on the abdomen, head and thorax. The hind femora are used to apply the wax to the wings. The adults are normally active and run rapidly over plant surfaces. When disturbed, they either feign death or fly. Flight is fluttery and usually ends with a landing on the underside of vegetation. Meinander (1972) treated the genitalia extensively in his revision; therefore a comprehensive study is not included here. Discussions of genitalia are included under each genus and species heading. With few exceptions, Meinander followed the interpretation and termi¬ nology of Tjeder (1970). I have followed the terminology of Meinander, although occasionally differing from his interpretation. Mating in Coniopterygidae is apparently accomplished by either of 2 methods: Parasemidalis sp. (Withycombe 1922) and C. pineti- cola (Collyer 1951) mate in a staggered parallel position with the male bending the tip of the abdomen dorsally to meet the female terminalia; A.juniperi mate with the male and female in a tail-to-tail position (Henry 1976). 1 have found 4 species of the subfamily 266 Psyche [Vol. 87 Coniopteryginae (2 in Semidalis and 2 in Conwentzia) to mate in the staggered parallel position similar to that reported by Collyer. Eggs are laid singly on vegetation, frequently along leaf margins (Withycombe 1923) or on the underside of leaves near the midrib (Quayle 1912). Muma found S. vicina to produce 2-5 eggs daily for 16-25 days for a maximum of 266 eggs per female. Adult longevity varies with environmental conditions. Muma (1967) found S. vicina adults to live about one month. The Coniopterygidae are divided into 2 subfamilies: Key to subfamilies One radio-media cross-vein in middle of fore wing. Galea one-segmented. No plicaturae on abdomen. .Coniopteryginae Apparently two radio-medial cross-veins in middle of fore wing (either actually two radio-medial cross veins or one and Mi+ 2 and R4+5 briefly coalesce with the part of R4+5 between the point of fusion and the stem of Rs appearing as a second cross-vein). Galea three-segmented. Plicaturae present on abdomen . . Aleuropteryginae Subfamily Aleuropteryginae Enderlein, 1905 Aleuropteryginae Enderlein, 1905:225. Type: Aleuropteryx Low. Head capsule dorso-ventrally elongated in lateral view, genae long. Galea with basigalea and terminal knob. Fore wing with 2 radio-medial cross-veins and possible basal cross-vein. M has 2 setae in middle of wing, the bases of which are enlarged (except Bidesmida and possibly 2 other genera pot in the area of this study). M frequently narrowed between setae. In hind wing, M and Cui run close to each other for more than half the length of Cui; frequently without any membrane showing between them. Rs branches off from R near base of wing. Radio-medial cross-vein strikes stem of Rs basally of radial cross-vein and strikes M (when M is forked) on the anterior branch. Plicaturae present on sterna 3-6. Wax glands of abdomen in a narrow transverse band on each of first eight terga (except one genus not in area of present study) and surrounding plicaturae. Eighth segment normally with stigmata. Ninth segment of males strongly sclerotized. 1980] Johnson — Review of Coniopterygidae 267 Larvae with antennae and labial palpi of about equal length. Jaws long, slender, projecting from beneath labrum for more than half their length. Notes: There are 4 known genera of this subfamily within the area of this study. Key to North American genera of Aleuropteryginae 1. Radial cross-vein in hind wing strikes Rs on branch R2+3 . • • .2 Radial cross-vein in hind wing strikes Rs on stem or on fork . Aleuropteryx 2. Seventh sternum of male with plicaturae.3 Seventh sternum of male without plicaturae. Helicoconis 3. Bases of medial setae distinctly thickened. Neoconis Bases of medial setae not distinctly thickened. Medial setae not prominent. Bidesmida Genus Aleuropteryx Low, 1885 Aleuropteryx Low, 1885:79. Type, by monotypy, Aleuropteryx Lowii Klapalek, 1894. Antennae distinctly separated. Eyes small to medium. Head cap¬ sule and palpi usually dark. Antennae 19-27 segmented. Scape and pedicel elongate; male pedicel with distinct ventral spine. Flagellar segments varying in length, usually as long as or longer than broad; hairs not arranged in distinct whorls. Palpi unicolorous and slender, last segments of both labial and maxillary palpi only slightly broader than preceding segments. Basal segments of labial palpi distinctly longer than broad. Fore wings (Fig. 1) short, subtriangular, usually slightly more than twice as long as broad. Usually 2 basal cross-veins in costal area. Sc forks distally of radial cross-vein, which usually strikes R2+3, but sometimes strikes fork or stem of Rs. R4+5 coalesces with Mi +2 in most specimens, but may be connected by a cross-vein which superficially appears to be a branch of M. M not thickened at bases of setae. Cross-veins rs-m and m-cui strike M close to each other in middle of wing. Cu 2 sinuous, parallel with hind margin in all North American species. Sc, Ri, distal end of R2+3 and basal parts of Cui, Ai and A 2 thicker than other veins and bearing hairs. Longitudinal 268 Psyche [Vol. 87 Sc, Figure 1. Wings of Aleuropleryx werneri veins usually dark and cross-veins light, except CU 1 -CU 2 and posterior part of cross-vein m-cui, which are dark. Marginal fringes short. Hind wings usually slightly more than twice as long as broad. Usually 2 basal cross-veins in costal area. Sc forking distally of radial cross-vein, which strikes stem of Rs. Sc and distal parts of Ri and R2+3 thicker than other veins and having hairs. Marginal fringe short. Abdomen weakly sclerotized with limits of terga and sterna somewhat indistinct. Distinct plicaturae on segments 3-6 in both sexes and occasionally discernible on segment 2. Single narrow dorsal band of wax glands on segments 2-8 and surrounding plicaturae. Male genitalia strongly sclerotized and basically internal. Ninth tergum obliterate. Ninth sternum modified, dorsally fused in all 1980] Johnson — Review of Coniopterygidae 269 North American species to form a ring through which the penis protrudes. Ventrally and anteriorly, 9th sternum has lateral apoph¬ yses (except in 2 species not within the area of this study). Ventrally and posteriorly, 9th sternum has an unimpaired structure called the process of the 9th sternum. Originating anteriorly of the process are paired structures called the appendages of the 9th sternum. They are usually backwards and dorsally directed, bear hairs at their apical ends and are either fused distally or are connected to a transverse plate. Appendages of 9th sternum are frequently membranous and difficult to delimit. Penis prominent with a pair of dorsolateral apodemes and a somewhat conical anterior one. Ectoprocts un- sclerotized in all North American species, but sclerotized or other¬ wise modified in some other species. Female genitalia with ectoprocts often indistinct. Gonapophyses laterales forming a sclerotized ventral plate. Bursa copulatrix sclerotized and differing interspecifically. Notes: The male genitalia of Aleuropteryx differ from those of other genera and it is difficult to find homologous structures in other genera. The naming of structures in this case is for conveni¬ ence and an attempt is made to standardize terminology. This has not always been the case in the past (Meinander 1972). The shape of the bursa copulatrix and associated structures allow the females to be determined to species. The larval stages of only one North American species (A. juniperi ) is known. There are 14 species of this genus within the area of this study, 5 of which are herein described as new. Key to species — males 1. Wings with distinct brownish spots. punctata Wings without distinct spots .2 2. A pair of upward directed processes anterior to the process of the 9th sternum.3 No such processes present .7 3. Processes anterior to process of 9th sternum longitudinally flattened, plate-like and short .4 Processes anterior to process of 9th sternum spine-like and long.5 270 Psyche [Vol. 87 4. 5. 6 . 7. 8 . 9. 10 . 11 . 12 . 13. Process of 9th sternum ending in a central, caudally directed, pointed process. .cupressi Process of 9th sternum not as above. werneri Process of 9th sternum with 4 caudally directed processes, 2 central and 2 lateral. dragoonica Process of 9th sternum ending in 3 processes, 1 central, 2 lateral . 6 Caudal projections of process of 9th sternum subequal in length.... arceuthobii Central caudal projection of process of 9th sternum much larger than lateral ones. knowltoni Sclerotized structure present just ventral to dorsal roof of 9th sternum.8 No such structure present.10 Structure just ventral to dorsal roof of 9th sternum with 4 caudal projections. simillima Structure with 2 caudal projections.9 Two caudal projections strongly curved forward at the tip to form pronounced hook. maculipennis Two caudal projections only slightly bent ventrally at tip .. . arizonica Penis ending posteriorly in 3 small, subequal projections ... . juniperi Penis not as above.11 Process of 9th sternum simple. vulgaris Process of 9th sternum with an incision; not simple.12 Penis ending posteriorly in 2 lateral processes. unicolor Penis ending posteriorly in a ventral and a dorsal process.. .13 Dorsal process of penis as long as or longer than ventral process. longipennis Ventral process of penis much longer than dorsal process .. . megacornis Aleuropteryx arceuthobii Meinander, 1975 Aleuropteryx arceuthobii Meinander, 1975 p. 28. Type: Holotype male; Colorado; USNM. Head: Dark brown. Antennae 20-25 segmented; brown. Scape and pedicel about twice as long as broad; proximal flagellar 1980] Johnson — Review of Coniopterygidae 271 segments about as long as broad; median and distal flagellar segments almost twice as long as broad. Ventral spine on male pedicel about one fourth the length of the segment from the distal end. Thorax: Brown with dark brown shoulder spots. Wings: In fore wing R 4+ s coalesces for a considerable distance with M 1+2. Cu 2 only slightly sinuous. Membrane of wing grey-brown with light areas around radial cross-vein and about the m-cu cross¬ vein. Membrane of hind wing light greyish. Length of fore wing 2.2-2.4 mm, hind wing 1.9-2.2 mm. Male genitalia (Fig. 2): Ring of 9th sternum dorsally forming a Figure 2. Aleuropteryx arceuthobii. Male genitalia, lateral view. folded horizontal plate. Process of 9th sternum with three caudal processes, 1 central and 2 lateral. Lateral processes slightly dorsad to central one and curving slightly dorsad. A pair of slender, dorsally directed spines arises cephally of process of 9th sternum and ending caudally of transverse plate. Appendages of 9th sternum connected distally to transverse plate and bearing 4 long setae on a pair of caudally directed processes postero-lateral to the transverse plate. Transverse plate with 2 curved processes directed dorsally, a laterally flattened ventral process and 2 short acute anteriorly directed processes. Apophyses of 9th sternum long and slender. Penis ending caudally in 2 lateral plate-like processes and a central cone-shaped process containing a duct. 272 Psyche rvol. 87 Female and immature stages unknown. Previous distribution: Colorado. New material examined: texas*: El Paso. VI-27-28-1976, 2 males, C. L. Sperka, blacklight trap: VI-3^t-1976, 1 male, C. L. Sperka, blacklight trap. Notes: The present specimens from Texas differ slightly from the holotype. The lateral processes on the 9th sternum are closer to the central process on the holotype than on the Texas specimens. The 3 Texas specimens have 20 antennal segments and the holotype has 25. The wing length of the holotype is within the range of the wing lengths of the Texas specimens. The length of the coalescence of R4+5 and Mi +2 is long in all specimens but varies considerably. In 1 specimen, the coalescence begins near the radio-medial cross-vein in 1 wing and about halfway between the radio-medial cross-vein and the fork of M in the other wing. Meinander considered the paired processes caudo-lateral to the transverse plate to be part of the transverse plate. I prefer to consider them to be part of the appendages of the 9th sternum. They bear setae, which is consistent with their being part of the appen¬ dages of the 9th sternum. Meinander also described the dorsal roof of the 9th sternum as having a deep caudal incision. The caudal part of the roof of the 9th sternum has a median area which is lightly sclerotized in comparison with lateral areas and this gives the appearance of a deep caudal incision. Aleuropteryx arizonica Johnson, new species Type: Holotype male; Arizona; INHS. Head: Brown. Antennae 19-22 segmented; brown. Scape and pedicel twice as long as broad; first flagellar segment and distal flagellar segments about as long as broad; median flagellar segments slightly longer than broad. Ventral spine on male pedicel slightly basal to distal end. Thorax: Brown with blackish brown shoulder spots. Wings: In fore-wing R4+5 coalesces with Mi +2 for a distance varying with specimen from long to short. Cu 2 distinctly sinuous. Membrane of fore-wing greyish with darker shades along margin between veins. Hind-wing lighter without darker shading. Length of fore-wing 1.9-3.4 mm, hind-wing 1.7-3.0 mm. 1980] Johnson — Review of Coniopterygidae 273 Male genitalia (Fig. 3 A-C): Ring of 9th sternum dorsally forming a horizontal plate. Process of 9th sternum large in lateral view with a downward directed flap, shield-shaped in caudal view. Appen¬ dages of 9th sternum lightly sclerotized, connected with transverse plate and bearing setae caudo-lateral to transverse plate. Transverse plate formed of 2 C-shaped structures, free dorsally and fused ventrally into a short ventrally directed process. Free ends flattened dorso-ventrally, truncate in dorsal view, somewhat pointed in lateral view. Penis ending posteriorly in 2 ventro-lateral processes and a central, cone-shaped process containing a duct. A pair of processes just ventral to dorsal roof of 9th sternum. Caudal ends slightly curved ventro-laterally. Anterior portions much flattened dorso-ventrally and very wide, joining together to form a slightly folded membranous sheath attached to penis and to lateral portion of ring of 9th sternum. Ectoprocts weakly sclerotized. Female genitalia (Fig. 3D-E): A well-sclerotized subgenital plate present. Bursa copulatrix a strongly sclerotized tube. Dorso-caudal- ly, a sclerotized structure, dentiform in lateral view and truncate in ventral view. Immature stages unknown. Holotype male: Arizona: Pinal Co., near Superior, Boyce Figure 3. Aleuropteryx arizonica. A. Male genitalia, lateral view. B. Male geni¬ talia, caudal view. C. Male genitalia, ventral view. D. female genitalia, laterial view. E. Female genitalia, ventral view. 274 Psyche [Vol. 87 Thompson Southwestern Arboretum, VII-11-1949, B. W. Benson, light trap. Paratypes: Arizona: Superior, Pinal Co., V-2-8-1946, 1 male, B. W. Benson, at light; VII-16-VIII-5-1948, 9 males 7 females, H. K. Gloyd, at light; Pinal Co., near Superior, Boyce Thompson South¬ western Arboretum, IV-26-1949, 1 female, B. W. Benson; VII-11- 1949, 5 males, B. W. Benson; Sabino Co., Catalina Mt., IV-4-1958, 1 male, M. Adachi; Chutum Vaya Cn., Baboquivari Mts., 3250', VIII-4-1966, 1 male 1 female, F. Werner family. Deposited: INHS, USNM, ARIZ; AUTH. Aleuropteryx cupressi Meinander, 1974 Aleuropteryx cupressi Meinander, 1974:218. Type: Holotype male; California; UCA. Head: Dark brown. Color of eyes of both sexes light brown. All segments of antennae of both sexes about twice as long as broad. Ventral spine of male pedicel situated slightly distad of middle of segment. Thorax: Dark brown. R 4+5 and Mi +2 of fore wing coalesces for a short distance. Cu 2 distinctly sinuous. Membrane of both wings unicolorous yellowish brown. Length of fore wing 3.2-3.6 mm, of hind wing 2.8-3.2 mm. Male eenitalia (Fig. 4A): Ring of 9th sternum rather broad, dorsally longitudinally folded and apically with a rather deep incision. Apophyses of 9th sternum long and slender. Process of 9th sternum posteriorly with a caudally directed tapering process and apically dorsally a pair of flattened upwards and backwards directed processes. Appendages of 9th sternum membranous and apically connected to transverse plate. Transverse plate in lateral view hook- Figure 4. Aleuropteryx cupressi. A. Male genitalia, lateral view. B. Female genitalia, ventral view. C. Female genitalia, lateral view (Redrawn from Mein¬ ander 1974) 1980] Johnson — Review of Coniopterygidae 275 like and apically backward directed and bifurcate. Penis ending apically in 1 dorsal, 2 lateral and 1 ventral spine. Ectoprocts weakly sclerotized. Female genitalia (Fig. 4B-C): A well-sclerotized subgenital plate present. Bursa copulatrix a strongly sclerotized tube with a pair of large transverse dorso-lateral apodemes. Apically dorsally a well sclerotized structure, which in lateral view is dentiform. Immature stages unknown. Distribution: California. New material examined: None. Notes: Description from Meinander (1974). I agree with Mein- ander that the apical ends of the appendages of the 9th sternum are attached to the transverse plate. It is likely that the appendages of the 9th sternum possess setae apically, although Meinander does not mention them in his description. All related species have such setae. Aleuropteryx dragoonica Johnson, new species Type: Holotype male; Arizona; USNM. Head: Brown, slightly reddish in some specimens. Antennae 20-22 segmented; brown. Scape and pedicel about twice as long as broad, proximal flagellar segments about as long as broad, median and distal flagellar segments 1.5 times as long as broad. Ventral spine on male pedicel sub-terminal. Thorax: Brown with dark brown shoulder spots. Wings: In fore wing, R 4+5 coalesces for a considerable distance with Mi +2 ; Cu 2 distinctly sinuous, brownish with lighter areas near veins. Hind wing with membrane lighter, greyish. Fength of fore wing 2.4-2 .8 mm, hind wing 2.1-2.4 mm. Male genitalia (Fig. 5A-C): Ring of 9th sternum dorsally forms a folded horizontal plate. Process of 9th sternum with 4 caudally directed processes: the 2 lateral ones originate on the dorsal surface, bend medially at about the midpoint in their length and curve dorsally; 2 median processes, 1 dorsal and 1 ventral. A pair of slender spines originate cephally of process of 9th sternum and end caudally of transverse plate. Spines project antero-dorsally for most of their length and then bend caudo-dorsally. Appendages of 9th sternum connected distally to transverse plate and bearing 4 setae caudo-laterally to transverse plate. Transverse plate with 2 curved processes free dorsally and joined ventrally to form a laterally 276 Psyche [Vol. 87 flattened downward directed process. Two short, acute, antero¬ lateral processes near point where processes join. Apophysis of 9th sternum short. Penis caudally with 2 ventro-lateral processes and a central, cone-shaped process bearing duct. Ectoprocts weakly scle- rotized. Female genitalia (Fig. 5D-E): Gonapophyses laterales strongly sclerotized to form an unpaired ventral plate. Bursa copulatrix strongly sclerotized, long. Immature stages unknown. Holotype male: Arizona: Cochise Stronghold, Dragoon Mts., VIII-15-18-1969, R. J. Shaw, light trap. Paratypes: Arizona: Cochise Stronghold, Dragoon Mts., VIII- 18-21-1969, 1 female, R. J. Shaw, light trap; IV-l 7-21-1970, 1 male, R. J. Shaw, light trap; VI-10-15-1970, 2 females, R. J. Shaw, light trap; VI-15-20-1970, 1 female, R. J. Shaw, light trap; VII-24-27- Figure 5. Aleuropteryx dragoonica. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Male genitalia, ventral view. D. Female genitalia, lateral view. E. Female genitalia, ventral view. 1980] Johnson — Review of Coniopterygidae 277 1970 1 male, R. J. Shaw, light trap; VIII-6-9-1970, 1 female, R. J. Shaw, light trap; VIII-12-16-1970, 1 female, R. J. Shaw, light trap; IX-9-14-1970, 1 female, R. J. Shaw, light trap; IX-21-28-1970, 1 female, R. J. Shaw, light trap. Deposited: USNM, ARIZ; AUTH. Notes: The females described above are associated with the males of A. dragoonica by similarities in size, coloration, antennal and wing characteristics and by similarities in distribution. Under the circumstances, it is not possible to state definitely that the above mentioned females are conspecific with A. dragoonica but they are assumed to be until shown otherwise. This species is named after the type locality, Dragoon Mountains. Aleuropteryx juniperi Ohm, 1968 Aleuropteryx juniperi Ohm, 1968:14. Type: Holotype male: Ger¬ many: Coll. Ohm. Head: Brown. Antennae 22-23 segmented, almost unicolorous greyish brown. Scape about twice as long as broad, pedicel about two-thirds the length of the scape. Ventral spine of male pedicel close to distal end of pedicel. Flagellar segments distinctly longer than broad. Thorax: Brown with blackish brown shoulder spots. In fore wing, R* +5 and Mm vary from short coalescence to connection by a cross-vein. Cu 2 distinctly sinuous. Membrane of fore wing greyish brown with irregular areas of dark shading, especially near margin. Length of fore wing 2.5-2.8 mm, hind wing 2.2-2.5 mm. Male genitalia (Fig. 6A): Ninth sternum rather narrow, dorsally with 3 lateral, caudally directed processes which are folded longi¬ tudinally. Process of 9th sternum simple. Appendages laterally C genitalia, lateral view. C. Female Figure 6. Aleuropteryx juniperi. pteryx juniperi. A. Male genitalia, lateral view. B. Female C. Female genitalia, ventral view. (Redrawn from Meinander, 1972) 278 Psyche [Vol. 87 flattened, large, connected by transverse plate. Appendages with small group of setae distally. Transverse plate formed of a pair of curved, dorsally directed processes which are ventrally connected. A pair of small ventral projections of transverse plate present. Penis ending posteriorly in 3 processes, 2 ventro-lateral and one central. Female genitalia (Fig. 6B-C): Gonapophyses laterales sclerotized, forming an unpaired genital plate. Bursa copulatrix with a strongly sclerotized anteriorly narrowed part and a posterior, less strongly sclerotized part. Immature stages described by Ward (1970). Previous distribution: Western and Central Europe and United States. New material examined: None. Notes: This species was recently reported from the United States for the first time (Henry 1974, 1976 and Flint 1974). It has apparently become well established and is extending its distribution westward in the U.S. (Flint, personal communication). This species feeds on scale insect pests of conifers, mainly Juniperus sp. Aleuropteryx knowltoni Johnson, new species Type: Holotype male; Utah; USNM. Antenna 23-25 segmented. Scape, pedicel and flagellar segments twice as long as broad. Ventral spine on male pedicel about one- fourth the length of segment from distal end. Thorax: Brown with dark shoulder spots. Wings: In fore wing R 4+5 coalesces for a considerable distance with Mi+ 2 . Cu 2 distinctly sinuous. Membrane of wings unicolorous with fore wing darker than hind wing. Length of fore wing 3.4-4.0 mm, hind wing 2.6-3.8 mm. Male genitalia (Fig. 7A-C): Ring of 9th sternum dorsally forming a folded horizontal plate, caudally with lateral areas heavily scle¬ rotized and central area only lightly sclerotized. process of 9th sternum with 3 processes, a backward directed and dorsally curving central process and 2 small slightly curved processes extending dorso-caudally. The small processes located dorso-laterally to cen¬ tral process. A pair of slender dorsally directed spine-like processes originating cephally of process of 9th sternum and ending caudally of transverse plate. Appendages of 9th sternum connected distally with transverse plate and having a pair of knob-like processes 1980] Johnson — Review of Coniopterygidae 279 .20mm i * Figure 7. Aleuropleryx knowltoni. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Male genitalia, ventral view caudo-lateral to transverse plate bearing 4 setae. Transverse plate formed of 2 curved dorsally directed processes joined ventrally to form a large laterally flattened ventral process and a pair of small, acute antero-lateral processes. Apophyses of 9th sternum short, laterally flattened. Penis ending posteriorly in 2 large, laterally flattened, lateral processes and a central cone-shaped process with duct. Female and immature stages unknown. Holotype male: utah: Logan, VI-29-1950, G. F. Knowlton. Paratypes: utah: Logan, VI-29-1938, 1 male, G. F. Knowlton and D. E. Hardy, at light; VI-19-1950, 1 male, G. F. Knowlton; College, VI-29-1938, 1 male, L. Cutler. Deposited: UTAH; AUTH. Notes: All specimens have been preserved in ethyl alcohol for a long time and have lost most of their color. Therefore, I have omitted references to color in the description. This species is dedicated to G. F. Knowlton. 280 Psyche [Vol. 87 Aleuropteryx longipennis Meinander, 1974 Aleuropteryx longipennis Meinander 1974, p. 218. Type: Holotype male; Baja California; UCA. Head: Dark brown to black. Antennae 24-26 segmented, dark brown to black. Scape and pedicel about twice as long as broad; first flagellar segment about as long as broad; most of remaining flagellar segments about twice as long as broad. Ventral spine of male pedicel about one-fourth the length of segment from distal end. Thorax and legs: Dark brown to black. Wings: R 4+5 and Mi +2 coalesces for short distance. Cu 2 sinuous. Membrane of wings unicolorous light grey-brown. Length of wings vary greatly: fore wing 2.5-4 .8 mm, hind wing 2.1-4.1 mm. Male genitalia (Fig. 8 ): Ring of 9th sternum dorsally forming a folded horizontal plate, apically curved ventrally then anteriorly for short distance. Small incision in caudal view. Process of 9th sternum with a horizontal backward directed flap with lateral areas thicker than central area, forming a dorsal incision in caudal view and with a rounded incision in ventral view, one-third the length of flap. Appendages of 9th sternum partly membranous, connected apically with transverse plate and bearing 4 short setae apically. Transverse plate rather small, formed by 2 curved processes joined ventrally and free dorsally. Two small acute antero-lateral processes slightly dorsal to point where curved processes join. Apophyses of 9 th sternum very long and slender. Penis ending posteriorly in 2 processes: a ventral dorsally curving, spine-like process and a more ,20mm * 1 1 Figure 8. Aleuropteryx longipennis. Male genitalia, lateral view. 1980] Johnson — Review of Coniopterygidae 281 anterior, cylindrical, dorsally directed process with duct. Ectoprocts weakly sclerotized. Female and immature stages unknown. Previous distribution: California and New Mexico; Mexico: Baja California. New material examined: utah*: Logan, VI-2-1938, 1 male, G. F. Knowlton, D. E. Hardy and G. S. Stains, at light. Notes: Meinander referred to the transverse plate as being between the apices of the apophyses of the 9th sternum in his description. He was apparently referring to the apices of the appendages of the 9th sternum. The present specimen is the 4th known specimen of this species. Aleuropteryx maculipennis Meinander, 1972 Aleuropteryx maculipennis Meinander, 1972, p. 45. Type: Holotype male; California; CAS. Head: Dark brown. Antennae 20-23 segmented, dark brown. Scape and pedicel about twice as long as broad; first flagellar segment about as long as broad to twice as long as broad; proximal flagellar segments 1.5 times as long as broad; median flagellar segments one 1.5-2.0 times as long as broad; distal flagellar segments slightly longer than broad to 1.5 times as long as broad. Ventral spine on male pedicel about one third the length of segment from distal end. Thorax: Dark brown with blackish brown shoulder spots. Legs dark brown with tarsi lighter. Wings: In fore wing R 4+5 coalesces with M 1+2 for a short to moderate distance. Cu 2 distinctly sinuate. Membrane of fore wing greyish-brown with darker shades along margin between veins. Lighter areas around r-m cross-vein and m-cu cross-vein. Some specimens with noticeable clear areas directly adjacent to veins. Hind wing lighter. Length of fore wing 2.2-3.8 mm, hind wing 1.9-3.4 mm. Male genitalia (Fig. 9A): Ring of 9th sternum dorsally forming a folded horizontal plate. Process of 9th sternum large in lateral view with a downward directed, shield-shaped flap, narrower in caudal view than the flap of A. arizonica. Appendages of 9th sternum connected distally to transverse plate and bearing setae just antero¬ lateral to transverse plate. Transverse plate formed of 2 curved 282 Psyche [Vol. 87 ro O 3 3 B Figure 9. Aleuropteryx maculipennis. A. Male genitalia, lateral view. B. Female genitalia, lateral view. C. Female genitalia, ventral view. processes joined ventrally to form a short ventral process. Free ends of processes directly dorsally, slightly dorso-ventrally flattened, pointed in lateral view and truncate in dorsal view. A pair of well sclerotized structures ventral to dorsal roof of ring of 9th sternum. Caudal ends of processes strongly sclerotized and bent forward ventrally to form hook-like structures. Anterior ends of structures broadened in lateral view and truncate. The ventral parts of these anterior ends broadened laterally and fused together to form a broad, somewhat membranous structure attached to dorsal and lateral sides of penis and also probably to ring of 9th sternum anteriorly and laterally. Penis ending posteriorly in 3 processes, 2 ventro-lateral spine-like processes slightly laterally flattened and a central cone-like process. Female genitalia (Fig. 9B-C): Gonapophyses laterales sclerotized and fused to form an unpaired median plate. Strongly sclerotized part of bursa copulatrix somewhat heart-shaped in lateral view and tri-lobed in ventral view. A complicated folded ventral apodeme present and a caudal dentiform structure which is strongly scle¬ rotized and easily visible externally. Immature stages unknown. Previous distribution: U.S.A.: California. New material examined: U.S.A.: Arizona*: Superior, Pinal Co., VII-16-VIII-5-1948, 5 males 10 females, H. K. Gloyd, at light; III- 19-1949, 1 female, B. W. Benson, at light; Pinal Co?, near Superior, IH-19-1949, 1 female, B. W. Benson, at light; Pinal Co., near Superior, Boyce Thompson Southwestern Arboretum, IV-26-1949, 1 male 1 female, B. W. Benson, light trap; VII-11-1949, 5 males, B. 1980] Johnson — Review of Coniopterygidae 283 W. Benson, light trap; Pima Co., Sonora Desert Museum, VIII-5-8- 1962, 2 males, W. L. Nutting and S. Oman, light trap; Ramsey Cn„ Huachuca Mts., X-19-1966, 1 female, F. Werner, U.V. trap; Chu- tum Vaya Cn., Baboquivari Mts., VI1I-4-1966, 1 male, F. Werner family, U.V. trap; Cochise Stronghold, Dragoon Mts., X-3-8-1969, 1 female, R. J. Shaw, light trap; V-l2-17-1970, 1 female, R. J. Shaw, light trap; VI-5-10-1970, 1 female, R. J. Shaw, light trap; VI-10-15- 1970, 1 female, R. J. Shaw, light trap; VI-15-20-1970, 1 female, R. J. Shaw, light trap; VI-2-24-1970, 2 females, R. J. Shaw, light trap; VI- 27-29-1970, 1 female, R. J. Shaw, light trap; VII-2-5-1970, 2 females, R. J. Shaw, light trap; VII-27-30-1970, 1 male, R. J. Shaw, light trap; VII-3l-VIII-2-1970, 1 male, R. J. Shaw, light trap; VIII- 3-6-1970, 1 male, R. J. Shaw, light trap; VIII-6-9-1970, 1 male, R. J. Shaw, light trap; VIII-9-12-1970, 1 male 1 female, R. J. Shaw, light trap; VIII-12-16-1970, 1 female, R. J. Shaw, light trap; Texas*: El Paso, VI-3-4-1976, 1 male, C. L. Sperka, light trap. Notes: Meinander described the transverse plate and the append¬ ages of the 9th sternum as 1 structure and considered this to be the appendages of the 9th sternum. He considered the transverse plate to be absent. Occasionally, the transverse plate is pulled out of the normal position behind the posterior end of the penis to a more ventral position and in this location it is difficult to delimit. A transverse plate is present and the appendages of the 9th sternum are attached to it and are somewhat membranous and not tubular as described by Meinander. Meinander speculated that the hook-like structures just ventral to the dorsal roof of the 9th sternum might attach either to penis or to the ring of the 9th sternum. They are definitely attached to the penis and appear to be attached to the ring of the 9th sternum. Related species have similar structures attached both to the penis and to the 9th sternum. Previously, this species was known from 2 males. The females described above are associated with the males of A. maculipennis by similarities in size, coloration, antennal and wing characteristics and by similarities in distribution. Under the circum¬ stances, it is not possible to state definitely that the above mentioned females are conspecific with A. maculipennis but they are assumed to be until shown otherwise. 284 Psyche [Vol. 87 Aleuropteryx megacornis Johnson, new species Type: Holotype male; Arizona, USNM. Head: Dark brown, almost black. Antennae 22e24 segmented, dark brown. Scape and pedicel twice as long as broad; first and second flagellar segments about as long as broad to slightly longer than broad; proximal flagellar segments 1.5 times as long as broad; median flagellar segments twice as long as broad; distal flagellar segments 1.5 times as long as broad. Ventral spine on male pedicel about one-fourth the length of the segment from distal end of pedicel. Thorax: Dark brown with black shoulder spots. Wings: In fore wing R 4+5 and M 1+2 coalesces for variable distance, Cu 2 sinuate. Membrane of wing unicolorous grey-brown, veins dark and well defined, hind wing lighter. Length of fore wing 2.8-3.4 mm, hind wing 2.5-3.0 mm. Male genitalia (Fig. 10A-C): Ring of 9th sternum dorsally forms a folded horizontal plate with a small incision in caudal view. Process Figure 10. Aleuropteryx megacornis. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Male genitalia, ventral view. D. Female genitalia, lateral view. E. Female genitalia, ventral view. F. Female genitalia, caudal view. 1980] Johnson — Review of Coniopterygidae 285 of 9th sternum with a horizontal, caudally directed flap, deeply bisected to form 2 backward directed spines. Appendages of 9th sternum partially membranous, joined at distal ends with transverse plate and bearing setae caudo-lateral to transverse plate. Transverse plate formed of 2 dorsally directed, C-shaped processes, joined ventrally. Just dorsal to juncture, 2 acute antero-lateral processes. Apophyses of 9th sternum long and slender. Penis ending posterior¬ ly in 2 processes. Postero-ventral 1 large, upward curved, widened anteriorly and narrowed posteriorly with sides extending dorsally on lateral edge in scoop-like shape. Antero-dorsal process of penis more or less cylindrical, arising dorsally within the hollow of the ventral process. Dorsal process bearing a duct. Female genitalia (Fig. 10D-F): Gonopophyses laterales strongly sclerotized, forming a ventral unpaired plate. Strongly sclerotized part of bursa copulatrix large with a large postero-dorsal apodeme. Immature stages unknown. Male holotype: Arizona: Cochise Stronghold, Dragoon Mts. V- 9-12-1970, R. J. Shaw, light trap. Paratypes: Arizona: Superior, Pinal Co., 1 female, VII-16-VIII- 5-1948, H. K. Gloyd, at light; Pinal Co., near Superior, Boyce Thompson Southwestern Arboretum, 1 female, IV-26-1949, B. W. Benson, light trap; Cochise Stronghold, Dragoon Mts., 1 male, V-9- 12-1970, R. J. Shaw, light trap; Bowie, Cochise Co., 1 male 2 females, VII-28-1970, S. Kozloski, U.V. trap; Willcox, 1 female, VIII-9-10-1970, S. Kozloski, U.V. trap; new Mexico: Las Cruces, 2 males 1 female, VI-30-1960, J. G. Watts; VIII-1-7-1975, 1 male, W. P. Morrison, light trap; Texas: El Paso, VII-15-16-1976, 1 female, C. L. Sperka, light trap. Deposited: USNM, INHS; AUTH. Notes: A. megacornis is similar to A. longipennis but differs in the shape of the penis and the process of the 9th sternum. Megacornis has a much larger ventral spine on the posterior end of the penis than does longipennis and the horizontal flap on the process of the 9th sternum is deeply incised in megacornis but shallowly incised in longipennis. The female specimens are associated with megacornis because of similarities in coloration, size, antennal and wing characteristics and distribution. It is possible that they represent a different species, but they will be considered as megacornis until shown otherwise. 286 Psyche [Vol. 87 Aleuropteryx punctata Meinander, 1974 Aleuropteryx punctata Meinander, 1974:220. Type: Holotype male; Mexico; Sinaloa; UCR. Head: Brown. Antennae 22e25 segmented. Scape dark brown, pedicel and proximal and medial part of flagellum light brown, then becoming darker distally. Scape and pedicel about twice as long as broad; proximal and distal flagellar segments slightly longer than broad; median flagellar segments 1.5 times as long as broad. Ventral spine on male pedicel about one-third the length of segment from distal end. Thorax: Brown with blackish brown shoulder spots. Femora dark brown; tibiae lighter with dark proximal and distal ends; tarsi light brown. Wing: In fore wing R 4+5 and M 1+2 coalesces for a considerable distance, CU 2 distinctly sinuate, in some specimens with a small vein between margin and Cu 2 where it runs closest to the margin. Membrane of fore wing light with darker shades along margin between veins, scattered patches of light shading and discrete brown spots around cross-vein-like part of Sc 2 , base of Rs, radial cross¬ vein, r-m and m-cu and around cross-vein-like part of R 4+5 . Length of fore wing 2.4-3.0 mm, hind wing 2.0-2.8 mm. Male genitalia (Fig. 11 A): Ring of 9th sternum dorsally forming a folded horizontal plate. Process of 9th sternum very large, high and broad in lateral view and narrow in caudal view with a downward directed caudal part. Appendages of 9th sternum partly membran¬ ous, connected apically with transverse plate and bearing setae caudo-lateral to transverse plate. Transverse plate formed of 2 C- shaped processes, joined ventrally. Ring of 9th sternum with a lateral pair of caudally directed, spine-like processes. A pair of processes just ventral to dorsal roof of ring of 9th sternum. Processes spine-like caudally; flattened and somewhat membranous anteriorly and covered with small denticles on the anterior half. Anterior end of processes attached to penis and probably to ring of 9th sternum. Penis ending posteriorly in a flat, ventral process and a dorso-medial cone-like process. Apophyses of 9th sternum short. Female genitalia (Figs. 11B-C): A well-sclerotized subgenital plate present. Bursa copulatrix a strongly sclerotized tube with 2 ventro-lateral apodemes. Bursa copulatrix surrounded by a large 1980] Johnson — Review of Coniopterygidae 287 Figure 11. Aleuropteryx punctata. A. Male genitalia, lateral view. B. Female genitalia, lateral view. C. Female genitalia, ventral view. unsclerotized folded tube, which ends in a small sclerotized knob with long setae. Immature stages unknown. Previous distribution: U.S.A.: Arizona; Mexico: Sinaloa. New material examined: U.S.A.: new Mexico*: Las Cruces, 1 male, VII-28-VIII-3-1975, W. P. Morrison, light trap; 1 male, V-3-6- 1975, W. P. Morrison, light trap; Mexico: Cholla Bay, 1 male, IV- 25-1959, M. S. Adachi. Notes: Meinander referred to the appendages of the 9th sternum and the transverse plate as a forward directed process. This was evidently due to the transverse plate and appendages of the 9th sternum being pulled forward out of their normal position behind the process of the 9th sternum. He erroneously considered the large process of the 9th sternum to be formed by the appendages of the 9th sternum. The process of the 9th sternum of A. punctata differs from the processes of maculipennis and arizonica mainly in size with that of maculipennis being larger. Female genitalia, description and illustration from Meinander. Aleuropteryx simillima Meinander, 1972 Aleuropteryx simillima Meinander, 1972:46. Type: Holotype male, Mexico (Baja California) CAS. Head: Brown; eyes generally large. Antennae brown. Scape and pedicel about twice as long as broad; flagellar segments varying from slightly longer than broad to 1.5 times as long as broad. Ventral spine on male pedicel n ear d istal end. 288 Psyche [Vol. 87 Thorax: Brown with dark brown shoulder spots. Fore wing: Brownish grey, with darker shade along margin between veins. Membrane lighter near veins. Some variation in color of wings with some specimens much lighter than others. In some specimens, darker shades along margin are very indistinct. Coalescence of R4+5 and M1+2 varies from long to short. CU2 distinctly sinuous. Membrane of hind wing lighter than fore wing. Length of fore wing 1.8-3.8 mm, hind wing 1.6-3.0 mm. Male genitalia (Fig. 12A-B): Ring of 9th sternum broad dorsally. Process of 9th sternum large and complex with a dorsal bifurcate part and a downward directed caudal part. Appendages of 9th sternum distally membranous and fused with transverse plate. Hairs present at apices. Transverse plate composed of 2 processes, fused ventrally and free dorsally. Dorsal part curved caudally. A sclero- tized structure present just ventral to dorsal roof of 9th sternum. This structure sheath-like anteriorly, connected to penis and ap¬ parently to ring of 9th sternum; posteriorly ending in 4 flat, caudally directed spines. Except for the tip of the spines, entire structure covered with small denticles. Ring of 9th sternum with a pair of lateral, triangular projections, directed medially and caudally. Mar¬ gin unevenly serrate. Penis ending posteriorly in a pair of ventro- Figure 12. Aleuropteryx simillima. A. Male genitalia, lateral view. B. Penis, lateral view. C. Female genitalia, ventral view. D. Female genitalia, lateral view. 1980] Johnson — Review of Coniopterygidae 289 lateral processes and a central comewhat cone-shaped process. Ectoprocts weakly sclerotized. Female genitalia (Fig. 12C-D): Gonopophyses laterales fused to form ventral plate. Bursa copulatrix strongly sclerotized. anteriorly curved dorsally. Dorsally of bursa copulatrix, a sclerotized, hori¬ zontal structure. This plate-like structure is more strongly sclero¬ tized along lateral and caudal margin and caudal margin bears several setae; ring-like in ventral or dorsal view. Immature stages unknown. Previous distribution: Northern Mexico and Texas. New material examined: Arizona*: Superior, Pinal Co., 1 male, V-2-8-1946, B. W. Benson, at light; Pinal Co., near Superior, Thompson Arboretum #1,1 male, VI-7-1946, H. K. Gloyd, light trap; Superior, Pinal Co., 1 male, VII-16-VIII-5-1948, H. K. Gloyd, at light; 1 male, IV-1949, B. W. Benson, at light; near Superior, 1 female, IV-26-1949, B. W. Benson, light trap; near Superior, Boyce Thompson Southwestern Arboretum, 3 males 9 females, B. W. Benson, light trap; 1 male, X-3-1949, B. W. Benson, light trap; Chutum Vaya Canyon, Baboquivari Mt., 3250', 1 male 3 females, VIII-4-1966, F. Werner family, U.V. trap; 8 mi. N. Vail, 4 males, VIII- 7-1966, F. Werner family, U.V. trap; Cochise Stronghold, Dragoon Mts., R. J. Shaw, black-light trap; 51 males 41 females from following dates: 1 female, VIII-12-15-1969; 1 female, IX-7-11- 1969; 1 male 2 females, IX-11-15-1969; 1 male, X-3-8-1969; 4 males 1 female, V-9-12-1970; 1 female, V-l2-17-1970; 1 male 2 females, V- 17-21-1970; 1 male, V-25-VI-2-1970; 1 male 1 female, VI-10-15- 1970; 2 males 2 females, VI-15-20-1970; 1 male 4 females, VI-20-24- 1970; 2 males 1 female, VI-29-VII-2-1970; 2 females, VII-2-5-1970; 1 male 1 female, VII-5-8-1970; 1 male 1 female, VII-8-10-1970; 1 male 3 females, VII-10-12-1970; 3 males 1 female, VII-12-15-1970; 2 males, VII-15-18-1970; 2 males, VII-18-21-1970; 1 male, VII-21-24- 1970; 4 males 2 females, VII-24-27-1970; 2 males 1 female, VII-27- 30-1970; 1 male 1 female, VII-3l-VIII-2-1970; 1 male 1 female, VIII- 3-6-1970; 2 males 4 females, VIII-6-9-1970; 2 males 3 females, VIII- 9-12-1970; 2 males, VIII-12-16-1970; 1 male 3 females, VIII-16-22- 1970; 1 male, VIII-22-27-1970; 2 males 2 females, VIII-27-IX-1- 1970; 1 male 1 female, IX-M-1970; 2 males, IX-4-9-1970; 1 male, IX- 9-14-1970; 2 males 1 female, IX-14-21-1970; 3 males, IX-21-28- 1970; Phoenix, 2 males 1 female, VII-13-1970, J. E. May, U.V. trap; Cochise Co., Bowie, 1 female, VII-29-1970, S. Kozloski, U.V. trap; 290 Psyche [Vol. 87 Willcox, 1 male, VIII-9-10-1970, S. Kozloski, U.V. trap; new Mexico*: Las Cruces, 1 male, X-9-1974, V. Johnson, blacklight trap; 1 male, IV-26-1975, V. Johnson, blacklight trap; 1 male, IV- 21-V-2-1975, W. P. Morrison, blacklight trap; 3 males 1 female, V- 13-23-1975, W. P. Morrison, blacklight trap; 2 males, VI-22-27- 1975, W. P. Morrison, blacklight trap; 1 male, VII-28-VIII-1-1975, W. P. Morrison, blacklight trap; 1 male, VIII-1-7-1975, W. P. Morrison, blacklight trap. Notes: This species was recently reported from Texas by Wheeler (1980). This was the first record from the U.S. Aleuropteryx unicolor Meinander, 1972 Aleruopteryx unicolor Meinander, 1972:48. Type: Holotype male; California; UCA. Head: Dark brown. Antennae dark brown, 21-23 segmented. Scape about 2.5 times as long as broad; pedicel twice as long as broad; proximal and distal flagellar segments about as long as broad; median flagellar segments 1.5 times as long as broad. Ventral spine on male pedicel almost at distal end. Thorax: Dark brown witn blackish brown shoulder spots. Fore wing with R 4+5 and M 1+2 coalescing for a distance varying from short to long. CU 2 sinuous. Membrane of fore wing greyish brown, hind wing lighter. Length of fore wing 1.8-3.0 mm, hind wing 1.6-2.7 mm. Male genitalia (Fig. 13A): Ring of 9th sternum dorsally forms a folded horizontal plate, process of 9th sternum large, with a dorsal pair of apophyses and a caudal apophysis. Appendages of 9th sternum distally membranous and connected to transverse plate. Appendages with setae at point of connection with transverse plate. Transverse plate represented by a pair of curved hooks, ventrally expanded and connected. Penis ending caudally in a large curved process. Ectoprocts weakly sclerotized. Female genitalia (Fig. 13B-C): Subgenital plate well sclerotized. Heavily sclerotized portion of bursa compulatrix spherical in lateral view, somewhat wider in ventral view. Apically, a transverse horizontal plate, sclerotized along the apical margin and possessing 2 setae. Previous distribution: California and Mexico (Baja California). New material examined: Arizona*: Superior, Pinal Co., 2 fe- 1980] Johnson — Review of Coniopterygidae 291 Figure 13. Aleuropteryx unicolor. A. Male genitalia, lateral view. B. Female genitalia, ventral view. C. Female genitalia, lateral view. males, V-2-8-1946, B. W. Benson, at light; Cochise Stronghold, Dragon Mts., 1 male 1 female, V-l7-21-1970, R. J. Shaw, blacklight trap. Notes: Measurements above include those of Meinander and those of the new specimens from Arizona. The Arizona specimens account for the upper limits on wing measurements and the specimens of Meinander account for the lower limits. Meinander (1974) described the female genitalia from California specimens. At that time he illustrated and described 2 separate types of female genitalia. The type described as A. unicolor from Riverside, Cali¬ fornia, is identical to that of A. maculipennis newly described in the present work. The specimens he illustrated from Imperial Valley, California are what I consider to be A. unicolor. In addition, Meinander mentioned a 3rd type of genitalia from Mexico which probably represents another species. Aleuropteryx vulgaris Meinander, 1972 Aleuropteryx vulgaris Meinander, 1972:51. Type: Holotype male; Texas; USNM. Head: Dark brown. Antennae 20-24 segmented. Scape and pedicel dark brown; flagellar segments varying from light greyish brown to dark brown. Scape and pedicel 1.5 times to twice as long as broad; flagellar segments of male varying from as long as broad to 2.5 times as long as broad; female flagellar segments about 1.5 times as long as broad. Ventral spine on male pedicel about one- fourth the length of segment from distal end. Palpi brown. 292 Psyche [Vol. 87 Thorax: Dark brown with blackish brown shoulder spots; legs brown. Membrane of fore wing brown with lighter areas adjacent to veins, and between R and M. In some specimens this is marked and gives the appearance of darker areas along margin between veins. In some specimens R 4+5 coalesces for a long distance with Mi +2 and in others they are connected by a cross-vein. Cu 2 distinctly sinuous. Membrane of hind wing unicolorous, light greyish brown. Length of fore wing 1.7^1.1 mm, hind wing 1.5-3 .8 mm. Male genitalia (Fig. 14A): Ring of 9th sternum dorsally forming a folded horizontal plate. Process of 9th sternum simple, directed dorsally and caudally. Meinander (1972) reported the process ending in a small hook; the specimens at hand show only a very slight downward bend on the distal end. Appendages of 9th sternum distally membranous and attached to transverse plate. Setae present at distal ends. In some specimens a membranous structure can be seen extending from distal ends of appendages and apparently connected with ring of 9th sternum. Transverse plate composed of 2 processes ventrally connected with dorsal ends free and curved caudally. Penis ending posteriorly in 2 ventral plate-like processes and a dorsal truncate process. Ventral processes curved slightly dorsally. Ectoprocts weakly sclerotized. Figure 14. Aleuropteryx vulgaris. A. Male genitalia, lateral view. B. Female genitalia, ventral view. C. Female genitalia, lateral view. Female genitalia (Fig. 14B-C): Conapophyses laterals sclerotized, forming unpaired ventral plate. Bursa copulatrix strongly sclero¬ tized, at least in part, with a large, partially sclerotized apodeme. Heavily sclerotized portion of bursa copulatrix somewhat S-shaped in lateral view, with anterior part curved dorsally and posterior part bent ventrally. Immature stages unknown. 1980] Johnson — Review of Coniopterygidae 293 Previous distribution: Arizona, Calilornia, New Mexico, Texas and Utah. New material examined: Arizona: Pinal Co., Superior, 1 male 1 female, VII-16-VIII-5-1948, H. K. Gloyd, at light; Ramsey Canyon, Huachuca Mts., 1 male, VI-10-19-1966, F. Werner family, U.V. trap; Skull Valley, Yavapai Co., 1 male, VII-31-1970; Cochise Stronghold, Dragoon Mts., 47 males 67 females, R. J. Shaw, blacklight trap, following dates: 3 males 7 females, VIII-9-12-1969; 3 males, VIII-15-18-1969; 3 males 2 females, VIII-18-21-1969; 1 male, VIII- 24-27-1969; 2 males 1 female, IX-3-7-1969; 1 male 2 females, IX- 7-11-1969; 6 females, IX-11-15-1969; 1 female, V-21-26-1970; 2 males, V-25-V-12-1970; 1 male, VI-10-15-1970; 1 male 2 females, VI- 20-24-1970; 1 female, VI-27-29-1970; 1 male 2 females, VI-29-VII-2- 1970; 2 males 1 female, VII-2-5-1970; 1 male 2 females, VII-10-12- 1970; 1 female, VII-12-15-1970; 3 males 2 females, VII-15-18-1970; 2 males 2 females, VII-21-24-1970; 4 males 9 females, VII-24-27-1970; 1 male 12 females, VII-27-30-1970; 4 males, VII-27-29-1970; 1 male 5 females, VII-21-VIII-2-1970; 3 males 1 female, VIII-3-6-1970; 4 males 3 females, VIII-6-9-1970; 1 male 4 females, VIII-9-12-1970; 1 male 3 females, VIII-12-16-1970; 3 females, VIII-16-22-1970; 5 females, VIII-22-27-1970; 1 male 1 female, VIII-27-IX-1-1970; 2 males 2 females, IX-M-1970; 1 female, IX-4-9-1970; 1 female, IX- 14-21-1970; Coconino Co., Oak Creek Canyon, near Flagstaff, 2 females, IX-6-7-1973, M. M. Sanderson, blacklight trap; new Mexico: Las Cruces, 1 male, IV-21-V-2-1975, W. P. Morrison, blacklight trap; 1 male, V-l 5-24-1975, W. P. Morrison, blacklight trap; 1 male, V-22-27-1975, W. P. Morrison, blacklight trap; Texas: Lubbock, 1 male, VIII-9-14-1976, W. P. Morrison, blacklight trap; Utah: Washington Co., Leeds Canyon, 1 female, VII-28-1965, W. J. Hanson; Cache Co., Logan, 1 male, VII-3-1968, D. W. Davis, U.V. light; Cache Co., Green Canyon, 1 female, VII-27-VIII-2-1968, W. J. Hanson, malaise trap; Grand Co., near Moab, 1 female, V-30- 1974, Knowlton and Hanson. Notes: Meinander described A. vulgaris as lacking a transverse plate and with appendages of the 9th sterum “narrow and tube-like, ending free.” He apparently mistakenly identified the transverse plate as the terminal ends of the appendages. He also illustrated the penis as having a narrow pointed dorsal process. The process he illustrated is probably a lightly sclerotized connection between the penis and the ring of the 9th sternum. In lateral view, this does 294 Psyche fVol. 87 appear to be a spine like projection of the penis, although it is actually a wide, membrane-like connection. Meinander did not illustrate the blunt dorsal process of the penis which is difficult to see without close inspection. The sclerotized portion of the male genitalia of A. vulgaris is smaller than that of other species in North America, but is strongly sclerotized. The female of A. vulgaris is readily identifiable by the distinctive S-shaped appearance of the bursa copulatrix in lateral view. This can frequently be easily seen without clearing or dissecting the specimen. The females from Utah are the largest specimens examined and represent the top limits of the measurements given above. Aleuropteryx werneri Johnson, new species Type: Holotype male; New Mexico; USNM. Head (Fig. 15G): Dark brown, antennae 20-21 segmented, dark brown. Scape frequently darker than rest of antennae. Scape and pedicel twice as long as broad; most flagellar segments about 1.5 times as long as broad to twice as long as broad with median segments usually longest. Ventral spine of male pedicel about one- third to one fourth the length of segment from the distal end. Palpi brown. Thorax: Greyish brown with blackish shoulder spots; legs brown. Wings (Fig. 1): Dark, greyish brown. Coalescence of R 4+5 and Mi + 2 varies from long to short. Cu 2 distinctly sinuate. Length of fore wing 2.2-3.5 mm, hind wing 1.9-2.7 mm. Male genitalia (Fig. 15A-C): Ring of 9th sternum broad, longitu¬ dinally folded dorsally. Apophyses of 9th sternum rather short. Apically, the 9th sternum with a slight incision in lateral view caused by a dorsal and a ventral ridge running across it caudally. A pair of small spine-like processes dorso-laterally. A pair of flattened, upward directed processes situated medially and anteriorly to small spines. Appendages of 9th sternum membranous, attached apically to transverse plate and with group of setae at point of attachment. Transverse plate formed of 2 curved processes joined ventrally to form a long ventral spine and with a pair of caudo-lateral projec¬ tions just dorsal to where the 2 processes join. Penis ending 1980] Johnson — Review of Coniopterygidae 295 Figure 15. Aleuropteryx werneri. A. Male genitalia, lateral view. B. Male genitalia, caudal view. C. Male genitalia, ventral view. D. Female genitalia, lateral view. E. Female genitalia, ventral view. F. Female genitalia, caudal view. G. Male head, lateral view. posteriorly in 5 processes: a pair of ventro-lateral, dorsally curved, processes; a pair of laterally flattened processes originating medially to first 2 processes; a more or less central cone-like process with a duct. Ectoprocts weakly sclerotized. Female genitalia (Fig. 15D-F): A well sclerotized subgenital plate present. Bursa copulatrix with well sclerotized part curved upward apically in lateral view. A pair of large, dorso-lateral, transverse, sclerotized structures present; distinctive in lateral view. A tooth-like posterior projection dorso-caudal to bursa copulatrix. Immature stages unknown. Holotype male: new Mexico: Fas Cruces, VII-28-VIII-3-1975, W. P. Morrison, blacklight trap. Paratypes: new Mexico: 73 males 33 females. Fas Cruces, W. P. Morrison, light trap, following dates: 1 female, X-9-1974; 3 males, 296 Psyche [Vol. 87 IV-21 -V-2-1975; 25 males 13 females, V-10-25-1975; 2 males 2 females, VI-10-20-1975; 3 males 1 female, VI-21-27-1975; 2 males 1 female, VII-22-27-1975; 11 males 2 females, VII-28-VIII-3-1975; 10 males 10 females, VIII-1-7-1975; 17 males 3 females, VIII-8-20-1975. Deposited USNM, AUTH; ARIZ. Notes: There is a female from Idaho (Craters of the Moon National Monument, VII-7-1964; D. S. Horning, Jr.) which may be A. werneri. This species is related to A. cupressi Meinander but differs in the shape of the 9th sternum with A. cupressi having a median caudal projection lacking in A. werneri. There are other differences,