Rhamphomyia (Ctenempis) albopilosa Coquillett

Sinclair, Bradley J., Vajda, Élodie A., Saigusa, Toyohei, Shamshev, Igor V. & Wheeler, Terry A., 2019, Rhamphomyia Meigen of the Canadian Arctic Archipelago, Greenland and Iceland (Diptera: Empididae), Zootaxa 4670 (1), pp. 1-94 : 9-13

Rhamphomyia (Ctenempis) albopilosa Coquillett

( Figs 1–4 , 62A )

Rhamphomyia albopilosa Coquillett, 1900: 418 . Type-locality: Berg Bay, Alaska, USA.

Other references: Malloch, 1919: 47 (expedition results); Melander, 1928: 185 (catalogue); Melander, 1965: 461 (catalogue); Danks, 1981: 465 (arctic insects); Yang et al., 2007: 191 (catalogue).

Rhamphomyia calvimontis Cockerell, 1916: 123 . syn. nov. Type-locality: Baldy Mtn., Colorado, USA.

Other references: Melander, 1928: 187 (catalogue); Melander, 1965: 462 (catalogue); Yang et al., 2007: 192 (catalogue).

Rhamphomyia (Dasyrhamphomyia) wuorentausi Frey, 1922: 67 . syn. nov. Type-locality: Dudinka, Krasnoyarskiy Territory, Russia.

Rhamphomyia (Ctenempis) wuorentausi Frey : Frey, 1935: 3 (key and new subgenus); Frey, 1955b: 513 (revision).

Rhamphomyia (Rhamphomyia) wuorentausi Frey : Chvála & Wagner, 1989: 292 (catalogue); Yang et al., 2007: 191 (catalogue); Shamshev, 2016: 84 (checklist).

Notes on synonymy. The male terminalia of R. albopilosa and R. calvimontis are identical. They differ slightly on the basis of whitish setae on thorax and abdomen in the former compared to yellowish setae in the latter. Also legs generally with more numerous and longer setae in R. calvimontis , especially on the mid femur. The differences in setation are not considered to justify separate species recognition.

Type material examined. Rhamphomyia albopilosa : LECTOTYPE (here designated in order to fix identity of the species) ♂ ( Fig. 1A ), labelled ( Fig. 1B ): “ Berg Bay [Alaska]/ 6–10’99”; “ Harriman Expedition ’99/ T. Kincaid Collector ”; “ Type / No. 5227/ U.S. N.M. [red label]”; “ Rhamphomyia / albopilosa/ Coq.”; “USNMENT/ 01288291 [data matrix code]” ( USNM) . PARATYPE: not examined [not present in USNM] (1 ♂, USNM).

Rhamphomyia calvimontis : HOLOTYPE ♂ ( Fig. 1C ), labelled ( Fig. 1D ): “above timber/ line. Baldy / Mt. Col. / July 24. ’15./ (Cockerell) [hand written]”; “ALMelander/ Collection / 1961”; “ Rhamphomyia / calvimontis/ Ckll. TYPE. [hand written]”; “ HOLOTYPE / Rhamphomyia / calvimontis Cock. [red label]”; “USNMENT/ 01312581 [data matrix code]”; “ LECTOTYPE / Rhamphomyia albopilosa / Coquillett/ des. Sinclair & Saigusa 2018 [red label]” ( USNM).

Rhamphomyia wuorentausi : LECTOTYPE (here designated in order to fix identity of the species) ♂ ( Fig. 2A ), labelled ( Fig. 2B ): “Dudinka [Krasnoyarskiy Territory, Russia]”; “Wuorentaus”; “1584”; “Mus. Zool. H:fors/ Spec. typ. No. 4673/ Rhamph. wuo/ rentausi Frey”; “ LECTOTYPE / Rhamphomyia wuorentausi / Frey/ des. Sinclair & Saigusa 2018 [red label]” ( MZH) . PARALECTOTYPES: Same data as lectotype (1 ♀, MZH); Kantaika [= Khan- tayka, Krasnoyarskiy Territory , Russia], J. Sahlberg (1 ♀, MZH) .

Additional material examined. CANADA. Northwest Territories: Aklavik, 28.vi.1956, E.F. Cashman (1 ♂, CNC); Aklavik, 29.vi.–3.vii.1956, R.E. Leech (1 ♂, 2 ♀, CNC); Masik Riv., Banks Is., 3–29.vii.1968, W. R.M. Mason (16 ♂, 9 ♀, CNC); Masik Riv., Banks Is., 7–30.vii.1968, G.E. Shewell (16 ♂, 21 ♀, CNC); Reindeer De- pot, Mackenzie Delta, 10.vii.1948, J. R. Vockeroth (1 ♀, CNC); - 21 mi E Tuktoyaktuk, 20.vi.–21.vii.1971, D.M. Wood (10 ♂, 9 ♀, CNC); Victoria Is., 71°17′N 114°W, 8–28.vii.1975, G. & M. Wood (2 ♀, CNC). Nunavut: Baker Lake, 2–23.vii.1947, T.N. Freeman (2 ♂, 4 ♀, CNC); Baker Lake, 6.viii.1949, R.G., (1 ♂, 1 ♀, CNC); Bathurst Inlet, 5–19.vii.1951, C.D. Bird (2 ♀, CNC); Bernard Harbour, 68°47′06″N 114°49′43″W, 10.vii.1987, bait trap (2 ♂, CNC); Bernard Harbour, Dolphin & Union Str., 3–10.vii.1988, J. Troubridge (1 ♂, UGIC); Fraser Lake, 68°45′N, 120°36′W, 19.vii.1969, G.E. Shewell (4 ♂, 4 ♀, CNC); Head of Clyde Inlet, Baffin Is., 7.viii.1958, G.E. Shewell (9 ♂, 6 ♀, CNC); same data, J.E.H. Martin, (1 ♂, 6 ♀, CNC); Cambridge Bay, 12.viii.1959, J.A. Downes (1 ♀, CNC); Cambridge Bay, 69.1207°, -105.42582°, MT, mesic, 11–15.vii.2011, NBP field party, (25 ♂, LEM); Cambridge Bay, 69.12157°, -105.43124°, MT, 15–19.vii.2011, mesic, Repl.3, NBP field party (69 ♂, LEM); same data except, CCDB-21421-D01, CCDB-21421-E06 (1 ♂, 1 ♀, barcoded, LEM); Cambridge Bay, 69.12177°, - 105.41688°, sweep, 13–15.vii.2011, wet, Repl.1, NBP field party (5 ♂, LEM); Cockburn Point, Canadian Arctic Ex- pedition, 3.ix.1914, F. Johansen (1 ♀, CNC); Coppermine, 30.vi.–20.vii.1951, S.D. Hicks (4 ♀, CNC); Coral Har- bour, Southampton Is., 3–17.vii.1948, G.E. Shewell (27 ♂, 48 ♀, CNC); Coral Harbour, 15–16.viii.1959, W. R.N. Mason (2 ♂, 2 ♀, CNC); Coral Harbour, 16.viii.1959, J.A. Downes (1 ♀, CNC); Eskimo Point, 12–13.vii.1950, G.G. DiLabio (4 ♀, CNC); Eskimo Point, 17.vii.1950, G. R. Roberts (1 ♂, CNC); Muskox Lk., 64°45′N, 108°10′W, 11–18.vii.1953, J.G. Chillcott, (1 ♂, 2 ♀ CNC); Padley [Padlei], 24–27.vii.1950, R.E. Duckworth (2 ♂, 3 ♀, CNC); Padley, 1.viii.1950, R.A. Hennigar (1 ♀, CNC); Ross Bay, Melville Peninsula, N 66°51′ W 84°53′, 19–22.vii.1948, G.E. Shewell; Cody & McArthur (3 ♀, CNC); Spence Bay, 14.vii.1951, J.G. Chillcott (1 ♀, CNC). Quebec: Sugluk [Salluit], 14–22.vii.1954, H. Huckel (2 ♂, 4 ♀, CNC). Yukon: British Mts. Firth River, 27.vii.1956, R.E. Leech (1 ♂, CNC); British Mts., 69°15′N 140°02′W, 25.vi.1984, G. & M. Wood & D. Lafontaine (1 ♀, CNC); Dempster Hwy, mi 87, 27.vi.–12.vii.1973, G. & D.M. Wood (4 ♀, CNC); Dempster Hwy, km 141, 22–24.vi.1982, G. & M. Wood (1 ♂, 1 ♀, CNC); Firth River, 13–17.vii.1956, E.F. Cashman (3 ♀, CNC); Firth River, 13–14.vii.1956, R.E. Leech (1 ♂, 3 ♀, CNC); Herschel Is., 11–30.vii.1953, C.D. Bird (11 ♂, 23 ♀, CNC); Herschel Is., 24–29.vii.1971, D.M. Wood (5 ♂, 2 ♀, CNC); Herschel Is., 29–30.vii.1971, W. R.M. Mason (2 ♀, CNC); Herschel Is., 29.vii.1916, F. Johansen, Canadian Arctic Expedition (1 ♀, CNC); Herschel Is., 5–26.vii.1953, J.S. Waterhouse (9 ♂, 11 ♀, CNC); North Fork Crossing, mi 42, Peel Plt. Rd. 3500 ft, 24.vi.1962, P.J. Skitsko (1 ♀, CNC); North Fork Cross- ing, mi 42, Peel Plt. Rd. 3500 ft, 6.vi.1962, R.E. Leech (1 ♀, CNC); Whitehorse, 6.vii.1988, F. Brodo (1 ♂, CNC). USA. Alaska: Arctic NWR: Atigun Gorge, 600–1100 m, 68.48931°N 149.20343°W, riverside MT, 16.vii.2002 (1 ♂, UAM); Cape Thompson, 23.vii.1961, R. Madge (1 ♂, CNC); Kotzebue, 26.vi.1951, R.I. Sailer (1 ♂, USNM); Nome Area, mi 55 Kougarok Rd., 65°05′23″N 164°40′20″W, 20–26.vi.2005, MT, J & R. Skevington (21 ♂, 6 ♀, CNC); Schrader Lake, 69°30′N, 145°W, 3–5.vii.1972, K.W. Philip (1 ♂, 1 ♀, CNC). Colorado: Chasm Lake, 12000 ft, 5.viii.1958, R.L. Parker (1 ♂, USNM); Fall River Pass, 12000 ft, 12.vii.1934 [collector?] (2 ♂, USNM); Pike’s Park, 14.vii.1901, Johnson (2 ♀, USNM); Summit L./ Flats, Mt. Evans, 12800 ft, 7–24.vii.1961, C.H. Mann (16 ♂, 25 ♀, CNC); Summit L., Mt. Evans, 12800 ft, 24.vii.1961, J.G. Chillcott (7 ♂, 2 ♀, CNC); Summit L., Mt. Evans, 12800 ft, Marshy lake and stream margin, 24.vii.1961, J.G. Chillcott (1 ♂, 2 ♀, CNC); Mt. Evans, Rocky Slope, 13600 ft, 4.viii.1961, J.G. Chillcott (2 ♂, 3 ♀, CNC); Summit L., Mt. Evans, 12800 ft, 24.vii.1961, S.M. Clark (1♂, 1♀, CNC); Summit L., Mt. Evans, 12800 ft, 24.vii.1961, B.H. Poole (6 ♂, 6 ♀, CNC); Mt. Evans, 13000 ft, on tundra, 28.vii.1961, C.H. Mann (2 ♂, 9 ♀, CNC); Mt. Evans, 12000 ft, 3.viii.1961, W. R.M. Mason (1 ♀, CNC); Mt. Evans, 13200 ft, 19.vii.1961, W. R.M. Mason (2 ♂, 4 ♀, CNC); Mt. Evans, 14000 ft, 25.vii.1961, J.G. Chillcott (2 ♀, CNC); Mt. Evans, 14000 ft, 25.vii.1961, W. R.M. Mason (1 ♂, 2 ♀, CNC); Mt. Evans, 14000 ft, 25.vii.1961, B.H. Poole (5 ♂, 7 ♀, CNC); Mt. Evans, 14000 ft, 27.vii.1961, J. R. Stainer (1 ♂, CNC); Mt. Evans, 13200 ft, 28.vii.1961, S.M. Clark (1 ♂, 2 ♀, CNC). Idaho: Juliaetta (2 ♂, 3 ♀, USNM). Washington: Pullman, 20.v.1917, A.L. Melander (4 ♂, 8 ♀, USNM).

Diagnosis. This species is distinguished from other species of Ctenempis by the subshiny scutum, male sternite 6 with transverse cluster of stiff golden ventral setae and a pair of horn-like projections on male sternite 7. Females are without pennate setae on legs and wings are broader than males and more darkly infuscate.

Redescription. Wing length 6.0– 6.8 mm. Male. Head dark in ground-colour, with greyish pruinescence on face, frons, postgena and occiput; oral margin black and shiny. Holoptic, eyes with ommatidia larger on upper half of eye, smaller on lower half. Frons represented by very small triangular space below ocellar tubercle and larger subtriangular space above antennae; short, curved setulae along eye margin from ocellar triangle to antenna. Margins of face slightly divergent. Ocellar triangle dark with numerous setae of variable lengths. Upper half of occiput bearing row of long, black postocular setae, subequal in length with ocellar setae; upper occipital setae black and long; lower occipital setae pale, silky, hair-like, as long as upper occipital setae and distinctly denser on postgena. Antenna dark; scape slightly more than 2X longer than pedicel; postpedicel nearly 3X longer than basal width; stylus nearly as long as scape. Palpus dark, bearing many long, dark setae. Clypeus reddish, base glossy with thin pruinescence apically; labrum dark and glossy, length 2X eye height; labellum dark and bearing many dark setae, shorter than palpal setae.

Thorax dark with dense grey pruinescence on pleura, scutum somewhat subshiny; darker grey to black vittae between acr and dc rows extending to prescutellar depression. Pleura with orange tint along notopleural ridge, as well as on posterior margin of katepisternum; pleural sclerites with variable pronounced shadows of brown; anterior and posterior spiracles pale brown. Proepisternum and prosternum ( Fig. 3D ) with many long, pale to golden setae; similar setae on upper part of proepisternum in front of anterior spiracle. Antepronotum with cluster of long, pale, lateral hair-like setae; middle part with many short, pale setae. Postpronotal lobe clothed in long, hair-like, pale setae with 1 outstanding pprn. Mesonotal setae long, mostly hair-like, becoming stouter, darker and sparser posteriorly (southern specimens with all dark setae): acr biserial; dc and presut spal multi-serial; notopleuron with dense anterior cluster of shorter (no shorter than ac), pale, hair-like setae; posterior notopleuron with row of 4–6 stout, golden setae, sometimes upper 1–2 dark; numerous thin prealar setae; 1–2 psut spal; 1–6 pal; 5 or more pairs of marginal sctl. Laterotergite with cluster of pale to dark, hair-like setae.

Legs long, entirely dark, darker than thorax ground colour. Anterior and lateral regions of mid and hind coxae with numerous long pale to dark setae; fore coxae bearing setae only anteriorly. Femora with dense ventral white pile ( Figs 3A, B ); arctic populations: mid and hind femora with row of thin anteroventral setae, shorter than width of femur; fore femur without anteroventral row; southern populations with anteroventral row of stouter, dark setae on all femora; row of long posteroventral setae on fore and mid femora. Fore and mid tibiae clothed with white pile ventrally; mid tibia with posteroventral row of dark setae, minute; tibiae with dark posterodorsal setae longer than tibial width, long and more numerous in southern populations. Fore tarsomere 1 slightly broader than fore tibia at apex, with ventral white pile; long anterior, anteroventral and posterior setae, longer apically; hind tarsomere 1 similar to foreleg (setae longer and more numerous in southern populations), without ventral pile; mid tarsomere 1 with ventral white pile; several anteroventral, ventral, and posteroventral dark, spine-like setae, never longer than tarsomere width (setae longer and stouter in southern populations).

Wing infuscate; pterostigma distinctly present as dark colouring; basal costal seta absent. CuA+CuP pigmented and reaching wing margin. Halter pale yellow (darker in southern populations); stem base darkened; row of dark setulae on base of knob.

Abdomen dark with pruinescence denser on margins of tergites and sternites. Abdomen clothed in long, thin pale to dark setae, nearly as long as length of corresponding sclerites. Sternite 6 inflated, cup-like with dense, transverse cluster of stiff golden setae ( Fig. 3C ). Tergite 6 expanded laterally over sternite, its diameter broader than that of other tergites; lateral setae shorter than that of other tergites; posterior corner prolonged, finger-like and curved downwards; margins of tergite 6 membranous and brownish. Tergite 7 bulbous, projecting anteriorly beneath tergite 6, laterally expanded to encircle spiracle; sternite 7 reduced medially, produced ventrally as two stout, rounded, finger-like projections ( Fig. 3C ). Tergite 8 reduced to narrow strip medially; barely visible in situ. Sternite 8 broader than tergite 8, bearing many long, hair-like, pale ventral setae; sternite 8 and tergite 7 with varying dark, lustrous regions.

Terminalia ( Fig. 3C ) darker than abdomen and clothed in pruinescence: epandrium convex laterally, subtriangular and pruinose with long, pale, hair-like setae along outer margin; posterior corner expanded with blunted margin. Cercus subtriangular with rounded corners, slightly longer than or subequal to length of epandrium; dorsal margin of cercus with 3 humps, lined with short, fine, dark, erect setae; cercus width less than half width of epandrium. Hypandrium large, visible beneath epandrium, heavily sclerotized, L-shaped, hugging swollen basiphallus, with slender apical extension. Basiphallus dark and glossy; distiphallus also relatively thick; without loops, not extending farther than cercus. Ejaculatory apodeme short, not heavily sclerotized, fan-shaped with anterior margin flat, without lateral “wings”.

Female. Similar to male except chaetotaxy of legs and thorax shorter and less dense; without pennate setae; wing darker and broader ( Fig. 62A ).

Distribution. This species is widespread across the low arctic, and in North America is primarily on the mainland with isolated records in localities south of the extent of glacial maximum ( Fig. 4 ). In the Palaearctic Region, this species occurs in Eastern and Western Siberia ( Russia) ( Shamshev 2016).

Remarks. Northern specimens are clothed in long, pale silky hair-like setae, whereas southern populations have darker stronger and more numerous setae, especially on the legs.

In the redescription of Rhamphomyia wuorentausi, Frey (1955b) states that the width of fore tarsomere 1 is three times the width of the fore tibia. It appears that the condition of the male specimens examined by Frey were rather shrunken which makes it difficult to judge the true width of the basitarsus. In better preserved specimens, the fore tarsomere 1 is only slightly wider than the fore tibia in this species. In addition, the density of the leg setae is rather variable, often with denser setae among more southern populations.

Figures

FIGURE 1. Rhamphomyia (Ctenempis) albopilosa Coquillett. A. albopilosa lectotype, lateral view; B. albopilosa type labels; C. calvimontis Cockerell holotype, lateral view; D. calvimontis Cockerell type labels (photographs @ Smithsonian Institute).

FIGURE 2. Rhamphomyia (Ctenempis) albopilosa Coquillett. A. wuorentausi Frey lectotype, lateral view; B. wuorentausi Frey type labels.

FIGURE 3. Rhamphomyia (Ctenempis) albopilosa Coquillett. A. Male forelegs; B. Male hindleg, anterior view; C. Male terminalia, lateral view; D. Female head and prosternum, lateral view.

FIGURE 4. Known distribution of Rhamphomyia (Ctenempis) albopilosa Coquillett in North America.

FIGURE 62. Wings of arctic Rhamphomyia. A. R. albopilosa, female, dorsal view; B. R. diversipennis, female, ventral view; C. R. diversipennis, male, ventral view; D. R. hilariformis, female, ventral view.