2 January 2007 PROC. ENTOMOL. SOC. WASH. 10% I ). 2007. pp. 208-222 THE IDENTITY AND DISTRIBUTION OF EFFERIA PLENA (HINE) AND E. NEMORALIS (HINE) (DIPTERA: ASILIDAE) The Arthropod Museum, Department of Entomology, University of Arkansas, Fayetteville. Arkansas 72701-1201, U.S.A. (e-mail: [email protected]) Ahsrrvr~~~.-Eflercrplencr (Hine) and E r?o~~oroli.s(Hine) from the eastern and south-central United States are redescribed and illustrated. These members OF the Effi.rin .stan?inecr species group are similar in appearance, and specimens of E. plena often have been misidentified as E. rzmzoro1i.r. Several characters for reliable identification of males are offered. Thc distributions of the species are mappcd. A lectotype is designated from the syntype series of Eras r?~~r?~oruli.~Hine. Key Words: Diptera, robber fly, Asilidae, Efferirr. Erau, Pogonieffirirr, Pogorrio<:fi /?ria, Nearctic Efleriu, with about 110 species recog- species groups, based largely on wing nized in the United Statcs (Poole 1996) characteristics. and more than 110 species in the more American species were assigned to southern reaches of the Americas (Mar- Era..: until Martin (1961) showed that tin and Papavero 1970), is one of the Macquart should have erected a new largest genera of Asilidae in the New genus for the American species. He World. Coquillett (1893) erected the recognized that Eflrriu is the first generic genus to receive a small group of North name available for the North and South American species previously referred to American species. Hull (1962), spparent- the old Palearctic genus Elvrr Scopoli, ly unaware of Martin's (1961) work, while leaving other North American stated that the New World species only species in that Old World genus. He superficially resemble the Old World subsequently (Coquillett 1910) designat- Er0.x species and proposed the new genus ed E carididn Coquillett as type species Nercr.~to receive the majority of Amer- of his new North American genus. ican species, while reserving Efjerio for Assignment of Western Hemisphere the species included in Hine's Err,.\- robber flies to Erax began with Mac- anoma1u.s group - the species in which quart (1838) and continued for a long the recurrent branch of vein R4 joins period. He assigned 29 species, most of Rz+, rather than ending blindly in cell them American, to the genus. Williston r~+~.Martin (1965) soon synomymized (1891) listed 74 species from South Neras under Effiria. In his revision of 4merica. In his Er0.r revision, Hine the North American species, Wilcox (1919) recognized 76 valid North Amer- (1966) followed Martin's (1961, 1965) ican species of Emx- sensu Macquart. interpretation of the genus Effhrir~and and he placed them in eight informal Hine's (1919) species group classifica- VOLUME 109, NUMBER I 209 tion. He described 30 new species and On closer examination, it was found that recognized a total of 100 species in North males of the two species differ in the America north of Mexico. color pattern of the third abdominal Artigas and Papavero (1997) divided tergite and in the form of the gonocoxite Efferia. They continued to recognize the and the apex of the epandrium. genera Diplosynapsis Enderlein and Por- Hine (1911) described Erax nernoralis nsil~~sCurran, removed Nernx from from several specimens, both male and synonymy, reserved Efferia for anom- female, collected at New Roads, Pointe ola-group species, and described the five CoupAe Parish, Lousiana, on July 15, new genera Albibarbefferia, Ariclefferia, 1905. Brolnley (1951) described Erax Cavinefferia, Pogoniefferia, and Tuhercu- monki from a male holotype collected lelferia to receive other species. (Artigas at Donna, Hidalgo County, Texas, on and Papavero (1997) used the spelling October 1, 1933. He distinguished it Pogoniefferia most frequently, but they from E. nemoralis by its smaller size, apparently misspelled it as Pogorzioef- more slender build, hyaline wings, white feria in one instance; the former spelling mystax and beard, darker legs, and more is here selected as correct.) These genera rounded male genitalia. Wilcox (1966) are nearly identical to Hine's (1919) did not study specimens of E. monki species groups, based on superficial before publishing his work on North differences in setation and wing venation American Efferia. He merely quoted that can vary among illdividuals of the Bromley's description, and did the best same species. Although the latest catalog he could in constructing the keys. Brom- of robber fly genera recognizes all of the ley (1951) indicated that the holotype Artigas and Papavero genera (Geller- was in the American Museum of Natural Grimm 2003), it is perhaps better to treat History, hut thorough searches of that them as synonyms of Efferia until in museum, the National Museum of Nat- depth phylogenetic analysis provides ural History, the California Academy of additional data upon which to base Sciences, the Texas A&M University a conclusion. Insect Collection, and several other New species of Efferia are still being museums and collections have failed to recognized and described in western produce any type specimens of E. monki. North America (Bullington and Lavigne A syntype series of E. nemoralis and the 1984; Forbes 1987, 1988), but it is rare to holotype of E. plana were located in the find new species in the East. While Charles A. Triplehorn Insect Collection, surveying the robber flies of the south- Ohio State University. I now regard E. central United States, it became evident morzki as a species inquirerzda, of doubtful that trays of Efferia nemoralis (Hine) at identity and needing further investiga- the University of Arkansas Arthropod tion. The holotype and some other Museum and other collections actually specimens were collected in the Gulf contained two species. Differences in Coastal region late in the season, sug- coloration of the vestiture of the mystax gesting that it might be junior a synonym and legs initially suggested the presence of E. nemoralis. of two species. A specimen with a mystax Study of the genitalia of the E plena that is interpreted as being "yellow or holotype and E. nemoralis lectotype, yellowish" keys to E. nemoralis, and designated herein, has led me to the a specimen with a mystax that is inter- conclusion that specimens of E. plena preted as being white keys to E. nzonlci have often been misidentified as E. (Bromley) in Wilcox's (1966) seminal nemoralis and placed in trays with monograph on North American Efferia. properly identified E. nernoralis. For this 210 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON reason, E. plena was recorded from only veins R4 and Rs is located basad to the Kansas and Oklahoma by Martin and level of the basal section of vein Mz Wilcox (1965) in their catalog of North (apex of cell d), and the male abdomen American robber flies, and its wide- has several silvery pollinose segments spread occurrence in Arkansas was not with long, parted, white hairs. Within recognized (Scarbrongh 1972, Whitcomb the staminea group, they are segregated and Bell 1964). Hine (1916) described from many other species by the black Erax plenus from a male holotype femora and white or yellow mystax. Both collected in Douglas County, Kansas. Efferia plena and Efferia nemoralis occur No date was given. That specimen and widely in Arkansas, where the former several others studied by Hine have species is apparently most abundant in a light colored abdominal tergite 7. One June, and the latter species is most specimen from Onaga, Pottawatomie abundant in July and August. Efferia County, Kansas has a dark colored plena has a wide distribution from Mary- tergite 7, but Hine (1916) dismissed this land and North Carolina in the East to condition as intraspecific variation. Kansas, Oklahoma, and Texas in the However, Wilcox (1966) admitted to no Midwest. Efferh nemoralis is strictly variation, and he identified only speci- a south-central species, occurring also mens with a "silvery pollinose" segment in Mississippi, Louisiana, northeastern 7 as Efferia plena. Most specimens of E. Texas, and southeastern Oklahoma. The plena that I have seen have a dark- ranges of the two species overlap in colored tergite 7, and they are identified Arkansas and Mississippi. Several char- as E. nenzorulis when using Wilcox's acters for reliable identification of males (1966) key. are described. No reliable characters In his revision of the genus Erax, Hine have been found separating the females (1919) separated male E. plena from male of the two species. E. nentoralis by the color pattern of abdominal tergites 1-3. The holotype of E. plena has the first three abdominal segments dark, mostly with black hair Terminology largely follows that found above (Fig. 1) That species is thus in the Manual of Nearctic Diptera (McA1- distinguished from E nemoralis, which pine 1981, Wood 1981). Antennomere to Hine describes as having male abdominal scape ratios were formulatedby dividing segments 1-2 and a basal triangle of the length of each antennomere by the segment 3 dark and largely clothed with length of the first antennomere (the scape) black hair, but the apex of 3 is white and and then listing the numbers in order. covered with long white hair parted in Specimens from the following collec- the middle and directed outward tions were studied: Colorado State Uni- (Fig. 4A). Unfortunately, there is a great versity, Department of Bioagricultural deal of variation in the color pattern of Sciences and Pest Management, C. P. abdominal tergite 3 of E. plena speci- Gillette Museum of Arthropod Diversi- mens, with many showing a well de- ty, Ft. Collins (CSUC); Mississippi State veloped white posterior band and long, University, Mississippi Entomological white parted hairs (Fig. 2). Even the Museum, Mississippi State (MEMU); holotype has some posterolateral white National Museum of Natural History, areas and some long, white hairs (Fig.