Rhamphomyia (Pararhamphomyia) ursinella Melander

Rhamphomyia (Pararhamphomyia) ursinella Melander

(Figs 48, 49)

Rhamphomyia ursina Malloch, 1919: 46. Type-locality: Bernard Harbour, Nunavut, Canada.

Other references: Cooper & Cumming, 1993: 33 (type catalogue).

Rhamphomyia ursinella Melander, 1928: 209 (replacement name for ursina Malloch, preoccupied by Oldenberg, 1915: 91). Other references: Melander, 1965: 466 (catalogue); Downes, 1970: 781 (behaviour); Danks, 1981: 465 (arctic insects); Yang et al., 2007: 200 (catalogue).

Type material examined. HOLOTYPE ♂ (Fig. 48C), labelled (Fig. 48D): “ HOLOTYPE / Rhamphomyia ursina Mall. / CNC No. 216 [red label]”; “Canadian/Arctic/Expedition/F.J. [F. Johansen] 1915”; “Sandy Beach/ July, 19 [hand written]”; “ Rhamphomyia /ursina/ Mall. Type [handwritten by Malloch?]” (CNC). PARATYPES: same data as holotype (1 ♀, CNC); same locality as holotype, July 1916 (1 ♀, CNC). There is an additional male specimen with the same label data as the holotype, but since there was no indication of the number of males examined and no range value provided for wing length, it is presumed that this specimen is not part of the type series.

Additional material examined. CANADA. Northwest Territories: Bailey Point, Melville Island, 21– 26.vii.1965, J.E.H. Martin (8 ♂, 11 ♀, CNC); Mould Bay, Prince Patrick Is., 3.vii.1952, P.F. Bruggemann (2 ♂, 1 ♀, CNC); same locality, 11.vii.1950, C.O. Handley (1 ♂, 6 ♀, USNM). Nunavut: Aklinck R., S. coast of Bylot Island, 1–27.vii.1954, R. S. Miller (1 ♂, 3 ♀, CNC); Axel Heiberg Is., 79°25′N, 90°45′W, 19–23.vii.1963, H.K. Rutz (2 ♀, CNC); Axel Heiberg Is., 79°25′N, 90°45′W, Gypsum Hill, 20.vii.1963, H.K. Rutz (1 ♂, 6 ♀, CNC); Cambridge Bay, 19–21.vii.1950, G.K. Seatman (2 ♀, CNC); Ellesmere Is., 79°58′N, 84°28′W, 7–14.vii.1988, 2.viii.1989, S.A. Edlund (3 ♂, 5 ♀, CNC); Ellesmere Is., Tanquary Fiord, 7.viii.1988, pan trap, S.A. Edlund (1 ♂, CNC); Eureka, Ellesmere Is., 3.viii.1963, J. R. Vockeroth (1 ♂, 1 ♀, CNC); Fosheim Peninsula, Hot Weather Creek, Ellesmere Is., 79°58′N, 84°28′W, 5.vii.1990, F. Brodo (1 ♂, 1 ♀, CNC); Hazen Camp, Ellesmere Is., 81°49′N, 71°18′W, 6.vii.1962, R. B. Madge (15 ♂, 34 ♀, CNC); Hazen Camp, 81°49′N, 71°16′W, 29.vi.1962, J.A. Downes (1 ♂, 1 ♀, CNC); Hazen Camp, 89°49′N, 71°18′W, 11.vii.1963, H.K. Rutz (1 ♀, CNC); Hazen Camp, 89°49′N, 71°18′W, 6.vii.1964, R. E. Leech (4 ♂, 4 ♀, CNC, in alc.); Lady Melville Lk., 69°25′N, 93°15′W, 3.vii.1951, J.G. Chillcott (8 ♀, CNC; 1 ♂, 1 ♀, UGIC).

Diagnosis. This dark-legged and darkly setose species is distinguished from other species of Pararhamphomyia by a shiny anepisternum, scutum with 1–2 pairs of shiny vittae and male hind tarsomeres 1–4 swollen with long setae dorsally.

Redescription. Wing length 3.6–4.5 mm. Male. Head dark brown in ground-colour, with light greyish pruinescence on face, frons and occiput. Holoptic, with ommatidia larger on upper half, smaller on lower half. Frons represented by very small triangular space below ocellar tubercle and larger subtriangular space above antennae, bare; face almost parallel-sided, slightly divergent towards mouthparts, bare with oral margin dark brown and shiny. Ocellar triangle dark, subshiny, with 1 anterior pair of parallel, slightly divergent dark setae and 1 posterior pair of setae, slightly shorter than the anterior ocellar setae. Occiput bearing row of dark, fine long postocular setae on upper half, with many fine, dark setae shorter than postocular setae; postgenal setae long, slender. Antenna mostly dark brown; pedicel and apex of scape slightly paler than postpedicel; scape slightly longer than pedicel; postpedicel about 2X longer than basal width; stylus slightly shorter than postpedicel basal width. Palpus dark, bearing many dark, long setae. Clypeus shiny; labrum lustrous and dark reddish brown, longer than head height; labellum dark and bearing fine, short, dark setulae.

Thorax dark reddish-brown in ground-colour, mostly covered in faint grey pruinescence. Scutum with pair of distinct lustrous vittae between acr and dc rows and sometimes with short vitta along supra-alar region. Pleura dark reddish brown, with lustrous patch on anepisternum. Proepisternum with few fine setae; upper proepisternum in front of spiracle bare; prosternum bare. Antepronotum with row of short, stout, dark setae. Postpronotum with several long, dark, fine setae and a few shorter anterior setae; pprn undifferentiated. Scutum with biserial fine, long dark acr; dc similar to acr, increasing in length and stoutness posteriorly; several undifferentiated presut spal; 3–4 npl, with several finer setae anteriorly; 0–2 prealar setae; several psut spal; 2 stout, long pal and several shorter setae; 5–6 pairs sctl. Laterotergite bearing fine, dark setae. Anterior and posterior spiracles dark.

Legs entirely brown, mostly lustrous; coxae with thin pruinescence. Hind and mid coxae with numerous dark lateral setae; fore coxa with many anterior setae. Femora with white ventral pile; fore and mid femora with anteroventral and posteroventral rows of long, numerous setae, nearly subequal in length to femur width; posteroventral row of mid femur more robust; hind femur with 1 anteroventral and 1 posteroventral row of short, fine setae, except anteroventral setae on apical 1/3 at least 3X longer. Tibiae (Fig. 48B) with numerous fine setae dorsally, at least 2X tibial width; anteroventral and posteroventral rows of fine setae, more robust on mid tibia; hind tibia mostly lustrous ventrally, with sparse, short, erect posteroventral setulae. Hind tarsomere 1 thickened apically (Fig. 48B), with numerous long, hair-like setae dorsally, 2X tarsal width, with 1 long seta in posteroapical comb; mid and fore tarsomere 1 not swollen, with numerous fine dorsal setae, some as long as 3X tarsal width. Hind tarsomeres 2–4 thickened, with numerous long, hair-like setae dorsally; mid and fore tarsomeres 2–4 not swollen, without long setae dorsally.

Wing infuscate with yellowish veins; all veins well sclerotized, except CuA+CuP faint, not reaching wing margin. Anal lobe well-developed, axillary excision obtuse. Pterostigma faint; basal costal seta absent. Halter brown.

Abdomen dark reddish brown, lustrous with sparse pruinescence. Margins of tergites and sternites pale. Abdomen clothed with dark, fine setae. Sternite 8 with many long, dark, marginal setae; ventral margin thinly sclerotized with apical notch; closely approximately laterally with tergite 8. Tergite 8 half length of sternite 8, narrowed medially, with fine marginal setae.

Terminalia (Fig. 48A) entirely dark. Epandrium elongate, slightly constricted in middle, bearing many fine setae, longer along ventral margin and apically. Cercus elongate, 2/3 length of epandrium; slightly constricted along middle section; dorsal margin bearing many short, fine setae; inner surface with slender, fleshy flap; apex short, with triangular ventral projection. Hypandrium slender, rectangular, ending at start of swollen phallus base. Phallus filamentous, with slight inward curve towards middle, forming elongate loop extending beyond epandrium and recurved between cerci; ejaculatory apodeme small, rectangular, with truncate dorsal margin, lateral wings subequal in size with vertical wing.

Female. Similar to male, except frons most bare; wing darker; leg chaetotaxy reduced, without pennate setae; hind tarsomeres not swollen.

Distribution. This species is widespread across the low to high arctic region of North America, east of Hudson Bay, but it has not been recorded from Greenland (Fig. 49). In the Palaearctic Region, specimens have been identified from Arctic Russia. Rhamphomyia caudata (Zetterstedt) is recorded from Spitzbergen in the Palaearctic catalogue (Chvála & Wagner 1989: 299), but it is likely R. ursinella or R. longestylata.

Remarks. Rhamphomyia ursinella is assigned to the R. caudata group (see Remarks section under R. filicauda). From comparison with type specimens, R. ursinella differs from R. longestylata Frey on the basis of longer setae on the hind tibia and tarsus, hind tarsomere 1 is somewhat swollen, the male cerci are broader apically than in middle with a triangular, ventral apical lobe and the epandrium is round apically. In contrast, R. longestylata has shorter setae on the hind tibia and tarsus, hind tarsomere 1 is parallel-sided and not swollen, the apex of the male cerci are narrower than in middle and smoothly rounded and the epandrium is angularly expanded apically.

Species unplaced to subgenus