Rhamphomyia cophas Walker, 1849

Sinclair, Bradley J. & Saigusa, Toyohei, 2018, Revision of Francis Walker’s female types of North American Rhamphomyia Meigen (Diptera: Empididae), Bonn zoological Bulletin 67 (2), pp. 129-143 : 130-132

Rhamphomyia cophas Walker, 1849

( Figs 1–5 )

Rhamphomyia cophas Walker, 1849: 499 . Type locality: New York, USA.

Rhamphomyia pulla Loew, 1861: 330 . Type locality: Connecticut, USA. Syn. nov.

Note about synonymy. Although the holotype of Rhamphomyia cophas is in very poor condition ( Figs 1, 3 ), features including leg colouration, body size and mid tibia chaetotaxy allowed for association with identified specimens of R. pulla . Although the male holotype of R. pulla , housed in the Museum of Comparative Zoology (see: http://140.247.96.247/mcz/Species_record. php?id=1016) possesses yellow femora and tibiae, female legs are much darker in this species, especially the mid and hind legs.

Type material examined. Rhamphomyia cophas : HOLOTYPE ♀, labelled ( Fig. 2 ): “Type [green margined circle]”; “?? Foster/ New York ”; “ N.York [on reverse side: 44/ 90”; “Walker’s/ measurements/ in error/ EAW 31.3.00”; “ One of Walkers / series so named./ EAW [on reverse side: “ Rhamphomyia / cophas/ Walk.]”; “not Ent. Club.”; “Cophas ,”; “ New York.”; “ Holo- / type [red margined circle]; “ BMNH (E) #/ 246916”; “NHMUK010210621 [data matrix code]” ( BMNH). The holotype is in poor condition, with left midleg, both hind legs, left fore tarsomeres 2–5 and abdomen missing; left wing is slide mounted (see Smith 1971, pl. 2, fig. 7).

Additional material examined. CANADA. Nova Scotia: Cape Breton Highlands NP, Pleasant Bay , 25–29. vi.1984, dry and wet mixed forest, H.J. Teskey (2 ♂♂, 2 ♀♀, CNC) . Ontario: Coldwater , 20, 30.v.1959, J.G. Chillcott (8 ♂♂, 6 ♀, CNC) ; Midland , swampy woods, 2, 26.v.1959, J.G. Chillcott (3 ♂♂, 3 ♀♀, CNC) ; Orillia , 7.vi.1925, 28.vi.1926, 16.vi.1927, C.H. Curran (5 ♂♂, 1 ♀, CNC) ( Fig. 4 ) ; Osgoode , 22.v.1964, J.R. Vockeroth (1 ♂, CNC) ; Ottawa , 30.v.1982, J.R. Vockeroth (1 ♂, CNC) ( Fig. 5 ) ; Simcoe , 2.vi.1939, G.E. Shewell (1 ♂, CNC) . Quebec: Beach Grove , 7.vi.1965, D.G.F. Cobb (1 ♂, CNC) ; Duncan Lake, nr. Rupert , 10.vi.1971, J.F. McAlpine (1 ♂, CNC) ; Gatineau Pk, King Mtn , 45°29ʹN, 75°51ʹW, 1.vi.2011, B.J. Sinclair (1 ♂, CNC) ; Knowlton , 20.vi.1927, G.S. Walley (1 ♂, CNC) ; Mt. St. Hilaire , 4.vi.1963, J.G. Chillcott (1 ♂, CNC) ; Norway Bay , 20.vi.1939, E.G. Lester (1 ♂, CNC) ; Old Chel- sea, 12.vi.1964, J.R. Vockeroth (1 ♂, CNC) ; Rigaud , 11.vi.1981, J.R. Vockeroth (1 ♂, CNC) . UNITED STATES OF AMERICA. Georgia: Towns Co., Tray Mtn , summit, 26.v.2000, G. & M. Wood (1 ♂, CNC) . Michigan: Charlevoix Co., 31.v.1960, R. & K. Dreisbach (3 ♂♂, 1 ♀, CNC) ; Delta Co., 11.vi.1960, R. & K. Dreis- bach (1 ♂, 1 ♀, CNC) ; Gratiot Co., 25.v.1958, R. & K. Dreisbach (2 ♂♂, 1 ♀, CNC) ; Mackinac Co., 7.vi.1957, 7.vi.1960, R. & K. Dreisbach (1 ♂, 4 ♀, CNC) ; Mecosta Co., 15.vi.1957, R. & K. Dreisbach (1 ♂, 1 ♀, CNC) ; Missaukee Co., 31.v.1957, R. & K. Dreisbach (1 ♂, 1 ♀, CNC) ; Ontonogan Co., 18.vi.1960, R. & K. Dreisbach (3 ♂♂, 1 ♀, CNC) ; Roscommon Co., 31.v.1957, R. & K. Dreisbach (1 ♂, 1 ♀, CNC) . New York: McLean Reserve, nr. Dryden , 11.vi.1964, J.G. Chillcott (1 ♂, 2 ♀♀, CNC) . North Carolina: Great Smoky Mtns NP, Noland Divide Tr. , 1700 m, 35°33ʹ58″N, 83°28ʹ37″W, 4.vi.2001, J.M. Cumming (2 ♂♂, CNC) . Ohio: Hocking Co., Coovert Reserve , 19.v.2003, hollow, J.M. Cumming (2 ♂♂, CNC) .

Diagnosis. Males of this species are distinguished by the dark abdomen, yellow femora and tibiae, with at least apex of hind tibia darkened; scape and pedicel yellowish; and upper digitiform process of sternite 7 projecting horizontally, lower process hook-like, arched dorsally; phallus with lower loop rectangularly curved and ridged expansion only slightly broader than shaft of phallus. Female have a darkened, shiny abdomen, mid and hind femora dark with yellowish tip and fore femur mostly dark with apical half yellowish.

Redescription. Wing length 6.2–7.4 mm. Male. Head dark in ground-colour, with greyish pruinescence on face, frons, postgena and occiput; oral margin shiny reddish. Holoptic, eyes with ommatidia very slightly larger on upper half of eye. Frons divergent towards antennal sockets, bare. Margins of face slightly divergent. Ocellar triangle with pair of slender ocellar setae, longer than postocular setae. Upper half of occiput bearing row of stout postocular setae, stouter than ocellar setae; lower postocular setae mostly slender and longer. Occipital setae black and stout. Antenna with scape, pedicel and extreme base of postpedicel yellow; postpedicel mostly dark, nearly 4× longer than basal width; stylus length subequal to basal width of postpedicel. Palpus yellow, bearing long, slender setae. Clypeus bare, reddish and glossy; labrum dark and glossy, longer than eye height; labellum dark and bearing many fine setae.

Thorax dark with dense grey pruinescence; brown to black vittae beneath acrostichal and dorsocentral rows extending to prescutellar depression; posterior corner of postpronotal lobe and postalar ridge yellowish brown. Pleura with yellowish brown highlights about suture lines. Prosternum bare; proepisternum at fusion point with prosternum with several dark setae; upper part of proepisternum in front of anterior spiracle bare. Antepronotum with dense row of long, stout setae. Postpronotal lobe with 1 outstanding seta and 8 or more shorter setae of various thicknesses; acrostichal setae uniserial, twothirds length of dorsocentral setae; dorsocentral setae uniserial, increasing in length posteriorly, prescutellar seta longer than lateral scutellar seta; 1 presutural supra-alar seta (= posthumeral), with several surrounding fine setulae; 3–4 notopleural setae, with several fine set- ulae anteriorly; 0 prealar setae; 1 postsutural supra-alar seta; 1 postalar seta and several shorter setae; 1 long apical pair and shorter lateral pair of marginal scutellar setae. Laterotergite with cluster of long, dark setae. Anterior and posterior spiracles blackish brown.

Legs long, stout; femora and tibiae yellow, apex of hind tibia often brown; coxae brown becoming yellowish apically. Coxae with lateral row of black setae. Femo- ra with dense white ventral pile. Fore femur with row of anteroventral and posteroventral setae increasing in length apically. Fore tibia with long, pale ventral pubes- cence; 2–3 anterodorsal and posterodorsal setae; apex with several dark setae. Mid femur with anteroventral and posteroventral rows of short, even-length stout setae; 1 dark anterior preapical seta. Mid tibia with anteroventral and posteroventral row of short stout setae; 2–3 anterodorsal and posterodorsal setae. Hind femur longer and stouter compared to other femora; anteroventral row of short stout setae increasingly closer together distally; two rows of 3–5 stout anterior setae on apical third. Hind tibia with long, ventral pubescence; 5–6 black anterodorsal and posterodorsal setae, shorter than width of tibia; apex with several dark setae; 1 long seta in posteroapical comb. Tarsomere 1 of all legs slender; ventral margin of all tarsomeres with dense ventral pile; hind tarsomeres with several pairs of spine-like ventral setae.

Wing lightly infuscate; pterostigma elongate, distinct; basal costal seta present. Cell dm shorter than cell bm; CuA+CuP complete, reaching wing margin without weakening; alular incision acute; margin of calypter with dark setae. Halter with whitish knob and yellowish stalk.

Abdomen dark brown, basal segment and tergites 7 and 8 with whitish pruinescence, remaining segments shiny; setae pale brown, lateromarginal setae on segments 2 and 3 long, stouter and darker. Sternites 2–6 with pair of very long, divergent median marginal setae, nearly as long as length of sclerite. Tergite 7 similar in width to tergite 6. Sternite 7 tapered apically to truncate margin, with 2 rows of long stout setae, becoming longer posteriorly; posterolateral margin expanded into cup-like process, bearing pair of short digitiform processes: upper process short, horizontally projected; lower process hook-like, arched dorsally. Tergite 8 more thickly sclerotized than tergite 7, expanded laterally at mid-length, fused to sternite. Sternite 8 slender, compressed between expanded posterolateral margins of sternite 7; bearing long, stout setae. Terminalia ( Fig. 5 ) dark brown, phallus pale brown. Hypandrium slender, strap-like, wrapping around base of phallus. Epandrium subrectangular, with rounded apex; posterior half clothed in long, stout setae; slightly longer than length of cercus. Subepandrial lobe lacking; bacilliform sclerite with dense, erect short setae. Cercus subrectangular with rounded apex; dorsal margin with triangular medial lobe at mid-length. Phallus slen- der with two deep loops, with lower loop rectangularly curved; sharply bent at mid-length at point of ridged expansion; expansion only slightly broader than shaft of phallus. Ejaculatory apodeme narrow, subtriangular; horizontal lamella on ventral margin.

Female. Similar to male except ( Fig. 4 ): frons with greyish pruinescence, glossy medially; margin with row of setae, uppermost shorter. Acrostichal row initially uniserial, biserial on posterior half. Mid and hind femora dark with yellowish tip and fore femur mostly dark with apical half yellowish; hind femur inflated, broader than other femora; femora without ventral pile. Abdomen mostly shiny, except for apical segments; setae pale, except pair of dark, divergent setae on sternites 2–5; dark, pilose pleural membrane, indicating retracted pleural sacs. Cercus long and slender, length 4–5 times width.

Geographic distribution. This species is widespread in eastern North America , ranging from northern Ontario ( Canada), south to North Carolina and Georgia (USA) and as far west as Michigan .

Remarks. Although the holotype of R. cophas is in poor condition, very greasy with abdomen and most of the legs missing, it can be readily assigned to the subgenus Calorhamphomyia Saigusa, 1963 on the basis of lustrous clypeus, leg colouration, thoracic chaetotaxy (prealar setae absent) and general body size. Saigusa (1963) assigned R. pulla to this subgenus.

Figures

Figs 1–5. Rhamphomyia cophas Walker. 1. Holotype, female, dorsal view; 2. Holotype labels; 3. Holotype, lateral view; 4. Recent specimen, female, lateral view; 5. Male terminalia, lateral view. See Additional material examined section for locality details of recent specimens.