Rhamphomyia poplitea Wahlberg, 1844

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 : 139-142

Rhamphomyia poplitea Wahlberg, 1844

( Figs 21–28 )

Rhamphomyia poplitea Wahlberg, 1844: 107 . Type locality: Quickjock , Sweden.

Rhamphomyia dana Walker, 1849: 502 . Type locality: St. Martin’s Falls [Ogoki], Albany River , Ontario, Cana- da. Syn. nov.

Rhamphomyia valga Coquillett, 1895: 428 . Type locali- ty: New Hampshire, USA. Syn. nov.

Note about synonymy. Females of this species are rather distinctive on the basis of the very long pennate setae ( Figs 23–24, 27 ) and R. dana matched females identified by Chillcott (1959) as R. valga . Rhamphomyia valga is assigned to the R. basalis Loew, 1864 group defined on the basis of the highly modified male hind leg ( Chillcott 1959). All species of the R. basalis group were examined in detailed in both the USNM and CNC and in combination with the key to females in Chillcott (1959) only one species ( R. valga ) matched the female Walker type.

Following the initial identification of R. dana with R. valga , it was learned that the European species, R. poplitea should also be assigned to the R. basalis group. Only digital images of the holotype of R. poplitea were studied. On the basis of identical colour of the abdomen, shape of the male hind leg and male terminalia R. valga is considered a synonym of R. poplitea .

Type material examined. Rhamphomyia dana : HOLOTYPE ♀, labelled ( Fig. 25 ): “Type [green margined circle]”; “ One of Walkers / series so named./ EAW [on re- verse side: “ Rhamphomyia / dana/ Walk.]”; “Dana ,”; “ St. Martin’s Falls,”; “ Pararhamphomyia / det. K.G.V. Smith, 1968”; “ Holo- / type [red margined circle]; “ BMNH (E) #/ 246917”; “NHMUK010210623 [data matrix code]” ( BMNH). The holotype is in good condition, with right postpedicel missing and left wing slide mounted (see Smith 1971, pl. 2, fig. 8).

Rhamphomyia poplitea : HOLOTYPE ♂, labelled ( Fig. 22 ): “Lp./ in. [Lapponia interior]”; “Bhn [Boheman collection]”; “Typus”; “poplitea, Wahlb. [unit tray la- bel]” ( NHRS).

Rhamphomyia valga : HOLOTYPE ♂, labelled: “ White Mts. / Morrison.”; “Collection/ C.V. Riley ”; “Type/ No. 3217/ U.S. N.M. [red label]”; “Rhamphomy- ia/ valga/ Coq.” ( USNM).

Additional material examined. CANADA. New Brunswick: Kouchibouguac NP, 5–14.vii.1977, J.R. Vockeroth, G.A. Calderwood (1 ♂, 2 ♀♀, CNC) . Newfoundland & Labrador: Fogo Island , vii.1929, C.W. Johnson (1 ♂, CNC) ; Goose Bay , 24.viii.1947, W.E. Beckel (1 ♂, CNC) ; same locality, 7.vii.1952 (2 ♀♀, CNC) . Ontario: Iroquois Falls , 21–30.vi.1987, J.R. Vockeroth (2 ♀♀, CNC) ; Thunder Bay Distr. , Neys Prov .

140 Bradley J. Sinclair & Toyohei Saigusa

Pk, Dune Trail , 48°46ʹ52″N, 86°36ʹ53″W, MT, yellow pans, 7–19.vii.2002, M. Buck (2 ♀♀, UGIC) ; Thunder Bay Distr., Prairie R. at Hwy 17, 38 km E Terrace Bay, 48°48ʹN, 86°47ʹW, boggy spruce MT, 15–19.vii.2002, M. Buck (2 ♂♂, 4 ♀♀, UGIC) . Quebec: Fort Chimo , 22.vii.1948, R.H. MacLeod (1 ♀, CNC) ; same locality, 7–9.vii.1954, J.F. McAlpine, E.E. Sterns (2 ♂♂, CNC) ; Indian House Lake , 9.vii.–15.viii.1954, W.R. Richards (31 ♂♂, 8 ♀♀, CNC) ( Figs 24, 27, 28 ) ; James Bay Rte, km 204.5, 50°58ʹ59″N, 77°38ʹ2″W, black spruce/ Sphagnum , MT, 7–16.vii.2001, M. & B. Buck (1 ♀, UGIC) ( Fig. 26 ) ; James Bay Rte, km 578.4, 53°32ʹ40″N, 77°40ʹ40″W, dry lichen conifer forest, yellow pans, 9–15.vii.2001, M. & B. Buck (1 ♀, UGIC) ; Knob Lake , 54°47ʹN, 66°47ʹW, 16.vii.1948, E.G. Munroe (1 ♀, CNC) ; La Ferme , 1.vii.1943, A. Robert (1 ♂, CNC) ; Laniel , 19.vi.1939, F.P. Ide (1 ♀, CNC) ; same locality, 21.vi.1941, A.R. Brooks (1 ♂, CNC) ; Parke Reserve , Ka- mouraska, 11–17.vii.1957, G.E. Shewell (3 ♀♀, CNC) . Yukon: Dempster Hwy , mi 87, 8–12.vii.1973, G.&D.M. Wood (1 ♀, CNC) ; Dempster Hwy , Eagle R. crossing; MT, 9–10.vii.1985, S.A. Marshall (1 ♂, UGIC) . FINLAND. Enontekis , Palmén (1 ♂, 1 ♀, MZH) , Enontekis, R. Frey (1 ♀, MZH) ; Muonio, R. Frey (1 ♂, MZH) ; Tien- su (1 ♂, MZH) . UNITED STATES OF AMERICA. Alaska: King Salmon, Naknek River , 3–14.viii.1952, J.B. Hartley (1 ♂, 1 ♀, CNC) .

Diagnosis. Females of this species are distinguished by long, broad and apically truncate dorsal and ventral pennate setae on the mid and hind femora and mid and hind tibia, longer than width of corresponding leg segment, and slender dorsal pennate setae on hind tarsomere 1; abdomen yellowish brown to pale brown, contrasting with grey thorax. Males are distinguished by the highly modified hind legs (characteristic of basalis group) and form of the male terminalia.

Redescription. Wing length 4.5–4.9 mm. Male. Head dark in ground-colour, with greyish pruinescence on face, frons, postgena and occiput; oral margin shiny reddish. Holoptic, eyes with ommatidia larger on upper half of eye, smaller on lower half. Frons divergent towards antennal sockets, bare. Margins of face slightly divergent. Ocellar triangle with pair of ocellar setae, shorter than postocular setae. Upper third of occiput bearing row of stout postocular setae, longer than ocellar setae; lower postocular setae slender and shorter. Occipital setae black and stout, extending ventrally; postgenal setae similar to occipital setae. Antenna dark; scape slightly longer than pedicel; postpedicel nearly 3× longer than basal width; stylus length about equal to length of scape. Palpus dark, slender, bearing single long, subapical seta. Clypeus bare, with greyish pruinescence; labrum dark and glossy, slightly longer than eye height; labellum dark and bearing many dark setae, shorter than palpal seta.

Thorax dark with dense grey pruinescence; brownish vittae beneath acrostichal and dorsocentral rows extending to prescutellar depression; posterior corner of postpronotal lobe and postalar ridge brownish. Prosternum bare; proepisternum at fusion point with prosternum with 1 stiff seta and sometimes several thinner setae; upper part of proepisternum in front of anterior spiracle bare. Antepronotum with row of setae. Postpronotal lobe with 1 outstanding seta and several shorter, finer setae; acrostichals biserial, slightly shorter than dorsocentral setae; dorsocentrals uniserial, increasing in length posteriorly, prescutellar seta slightly shorter than scutellar setae, dorsocentral row curved towards postpronotal lobe anteriorly; 1 presutural supra-alar seta (posthumeral) and 1 posterior supra-alar seta (opposite anterior notopleural) longer and stouter; 1 anterior and 3–4 posterior notopleural setae, with several setulae near anterior notopleural seta; 2 prealar setae; 1 postsutural supra-alar setae; 1 postalar seta; 1 long apical pair and short lateral pair of marginal scutellar setae. Laterotergite with cluster of long, dark setae. Anterior and posterior spiracles yellowish brown.

Legs short, brown with pale “knees”. Fore coxa with row of 5–6 stout anterolateral setae; lateral regions of mid and hind coxae with similar setae. Fore femur with row of fine anteroventral setae. Fore tibia with pale ven- tral pubescence. Mid femur with anteroventral row of short, even-length stout setae; posteroventral row of stout setae longer, greater than half width of femur. Mid tibia with anteroventral and posteroventral rows of very short, stout setae, shorter than ventral setae of femur. Hind femur greatly swollen, of uniform width on apical half ( Figs 21 , 28 ); anteroventral row of setae weak on basal half, stronger preapically; posteroventral row slender and long basally, decreasing evenly to setulae at apex. Hind tibia geniculate at base; straight, without crest of flattened setae and not flattened; setae of anteroventral row stout; anterodorsal setae numerous, some at least twice width of tibia; 1 long seta in posteroapical comb. Tarsomere 1 of all legs slender, with dense ventral setae.

Wing lightly infuscate ( Fig. 21 ); pterostigma elongate, normally pale; short basal costal seta present. Cell dm subequal in length to cell bm; CuA+CuP unpigmented, reaching wing margin as crease; alular incision obtuse; margin of calypter with brown setae. Halter pale yellowish brown.

Abdomen brown, paler than thorax; posterior margins of tergites and sternites paler; clothed in dark setae, longer along posterior margin; setae finer and somewhat paler on ventrolateral margin. Tergite 7 narrower than sternite 7, with posterolateral and posterior margin more thickly sclerotized. Tergite 8 reduced to half-length of sternite 8, narrowed laterally; posterior margin of sternite 8 with long setae, longer than length of sclerite 8. Terminalia ( Fig. 26 ) lighter brown, with apex of epandrium darkened. Hypandrium slender, wrapping around base of phallus. Epandrium subtriangular, produced posterior into slender rounded projection closed in very short, stout setae; posterior half clothed in long setae, some longer than half-length of epandrium. Subepandrial lobe digitiform; slightly arched with rounded apex; with 6–8 long setae on apical half. Cercus subrectangular with truncate apex, shorter than subepandrial lobe. Phallus broad and even throughout basal half; apical half strongly tapered and arched. Ejaculatory apodeme subtriangular, very large, as broad as length of hypandrium; horizontal lamella on posterior margin.

Female. Similar to male except: wing darkly infuscate ( Fig. 27 ), broader than in male. Legs with long, broad and apically truncate dorsal and ventral pennate setae on the mid and hind femora and mid and hind tibiae, longer than width of corresponding leg segment, and slender dorsal pennate setae on hind tarsomere 1 ( Figs 23–24, 27 ). Abdomen yellowish brown to pale brown, contrasting with grey thorax.

Geographic distribution. This species ranges across Canada and North America, from New Hampshire to Alaska (see Additional material examined). In the Palaearctic Region, R. poplitea occurs in Sweden, Finland and across Russia ( Shamshev 2016).

Remarks. This species (as valga Coquillett ) was includ- ed in the R. basalis group by Chillcott (1959). This species group is defined by the enlarged femur-tibia joint of the male hind leg ( Fig. 28 ) ( Chillcott 1959) and is as- signed to the subgenus Pararhamphomyia Frey, 1922 . Chillcott (1959) listed three European species that appear to be assigned to this species group on the basis of male genitalia, but apparently overlooked R. poplitea .

Figures

Figs 21–22. Rhamphomyia poplitea Wahlberg. 21. Holotype, male, lateral view; 22. Holotype label, upper three labels attached to specimen; lower label pinned to unit tray (photographs: Y. Brodin).

Figs 23–28. Rhamphomyia poplitea Wahlberg. 23. Holotype of R. dana Walker, female, lateral view; 24. Recent specimen, female hind leg, anterior view; 25. Holotype of R. dana Walker, labels, left label underside of corresponding label in centre row;26. Recent specimen, male terminalia, lateral view; 27. Recent specimen, female, lateral view; 28. Male hind leg, anterior view. SeeAdditional material examined section for locality details of recent specimens.