PROC. ENTOMOL. SOC. WASH. 89(3), 1987, pp. 559-561 A NEW SPECIES OF IRENANGELUS FROM COSTA RICA (HYMENOPTERA: POMPILIDAE: CEROPALINAE) Howard E. Evans Department of Entomology, Colorado State University, Fort Collins, Colorado 80523. Abstract. — Irenangelus eberhardi n. sp. is described from Costa Rica. This is the tenth known Neotropical species of these cleptoparasitic Pompilidae and the first to have been reared from a host (Auplopus semialatus Dreisbach). The pompilid genus Irenangelus has been known from nine Neotropical species and several from the Oriental and Australian regions (Evans, 1969). Although the genus has several unique features, common struc- tural characters with Ceropales suggest that, like members of that genus, these wasps are cleptoparasites of other Pompilidae. Wil- liams (1919) discovered this with respect to a Philippine species, /. luzonensis (Rohwer). He found a small larva attached to an egg of Tachypompilus analis (Fabricius) which had been laid ventrally near the base of the metasoma of the spider prey; he later reared several Irenangelus from Tachypompilus cocoons. He also reared an Irenangelus from a cocoon of Auplopus nyemitawa (Rohwer). Nothing further has been added in the more than half a century since Williams' report. Thus I welcome the opportunity to describe a new species from Costa Rica which has supplied further information on the biology of these rare and unusual wasps (Wcislo et al., in press). Irenangelus eberhardi Evans, New Species Fig. 1 Holotype female. — Length 7.5 mm; fore- wing 6.8 mm. Ground color yellow, marked with black as follows: greater part of man- dibles; extreme sides of clypeus; front with a pair of streaks from just above antennal sockets, nearly connecting with a band be- tween tops of eyes, also with a spot in front of median ocellus and a streak behind ocelli connecting to black on occiput; pronotum with a transverse band anteriorly; mesoscu- tum with three broad longitudinal bands; scutellum black anteriorly and posteriorly, otherwise yellow; postnotum black as well as two longitudinal stripes on propodeum; extreme base of first tergite black as well as broad apical bands on tergites 1-5; small streaks on mesopleura and along suture be- tween meso- and metapleura; mid and hind coxae streaked with black as well as inner surface of mid and hind femora and tibiae and outer surface of hind femora; tarsi yel- lowish brown. Scape yellow, flagellum black except apical 4.5 segments light reddish brown. Wings faintly tinged with yellow; ex- treme tip of forewing faintly clouded; stigma yellowish brown. Labrum emarginate, 2.0 times as wide as its median height; clypeus 1 .56 times as wide as its median height. Scape cylindrical; fla- gellum filiform, flagellomere 1 1.7 times as long as thick. Genae deeply grooved behind each eye, posterior margin of groove round- ed below, sharp above. Tubercle above an- tennal sockets well developed, bisected by a groove that extends to median ocellus; laterad of the groove the front is deeply pit- 560 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON Fig. 1 . Irenangelus eberhardi Evans, new species. Male genitalia, ventral aspect. ted all the way to eye margins and ocelli; vertex broadly depressed laterad of lateral ocelli. Mesoscutum with notauli distinct, linear, scutum without a median ridge; post- notum 0.7 times as long as metanotum, de- pressed and slightly broadened medially but not notably extended backward into pro- podeum, latter with a shallow median impression. All claws dentate. Third sub- marginal cell broader than second both above and below, receiving second recur- rent vein very slightly beyond middle. Allotype male. — Length 7.3 mm; fore- wing 6.8 mm. Color as in female except apical five segments of antennae light yel- lowish brown. Structure of head and thorax also as described for female; abdomen less tapered and compressed apically; last tergite shallowly emarginate; subgenital plate quadrate, wholly covered with short setae; genitalia as figured (Fig. 1). Variation. — The females vary in length from 7.5 to 9.5 mm, forewing length from 6.8 to 8.3 mm. In the larger females the black stripes on the front reach the trans- verse band across the vertex and the black streak on the outer side of the hind femora is absent. A paratype male is slightly larger than the allotype, measuring 8.4 mm, fore- wing 8.0 mm. There are no structural dif- ferences worthy of note. Type material. — Holotype $ and allotype 5, Costa Rica: Heredia, near Puerto Viejo, La Selva, 50 m. Reared from nest of Au- VOLUME 89, NUMBER 3 561 plopus semialatus Dreisbach, May 1986, W. Eberhard (Museum of Comparative Zool- ogy, Cambridge, Massachusetts). Paratypes: 1 $ and 1 (5, same data as type; 2 9, same data except dated April 1986 (Museum of Comparative Zoology and U.S. National Museum). Remarks. — This species resembles /. ich- neumonoides Ducke closely both in color and structure; these are the only known American species having deep punctures on the front. Structural differences from ich- neumonoides are as follows; smaller (7.3- 9.5 mm as compared to 9-14 mm in ich- neumonoides)\ labrum about twice as wide as high (barely wider than high in ichneu- monoides); scape without a sharp edge be- neath; punctures of front coarser and fewer in number; mesoscutum without a median ridge; male genitalia with parameres much exceeding digiti and parapenial lobes, re- curved tips of digiti less prolonged. Major color differences from ichneumonoides are as follows: antennal flagellum black except apically; front with a pair of black streaks but without a median streak; abdomen yel- low, prominently banded with black; inner surfaces of mid and hind tibiae streaked with black. Undoubtedly both species are mim- ics of species ofSte/opolybia (Vespidae), but judging from the differences in size and ab- dominal coloration it seems probable that they mimic different species of that genus. Etymology. — It gives me pleasure to name this species for William G. Eberhard, of the Universidad de Costa Rica, who collected the type series, in recognition of his many contributions to the biology of Neotropical insects and spiders. Literature Cited Evans, H. E. 1969. Studies on neotropical Pompili- dae (Hymenoptera) VII. Irenangeliis Schulz. Stud. Entomol. 12: 417-431. Wcislo, W. T., M. J. West-Eberhard, and W. G. Eber- hard. In press. Natural history and behavior of a primitively social wasp, Auplopus semialatus. and a parasite, Irenangelus eherhardi (Hymenop- tera: Pompilidae). J. Insect Behav. Williams, F. X. 1919. Philippine wasp studies. Bull. Exp. Stn. Hawaii. Sugar Plant. Assoc. (Entomol.) 14: 1-186.