Rhamphomyia taimyrensis Frey

Rhamphomyia taimyrensis Frey

(Figs 66, 67)

Rhamphomyia (Dasyrhamphomyia) taimyrensis Frey, 1950: 109. Type localities: Krasnoyarskiy Territory, shore of Taymyr Lake near mouth of Siruta-Yamu River; Amu-Tarida River, north-western Taymyr, Russia. Other references: Frey, 1955b: 520 (revision).

Rhamphomyia (Rhamphomyia) taimyrensis Frey: Chvála & Wagner, 1989: 291 (catalogue); Shamshev, 2001b: 342 (key); Yang et al., 2007: 189 (catalogue); Shamshev, 2016: 82 (checklist).

Material examined. RUSSIA. Arkhangelskaya Prov. (Novaya Zemlya Archipelago): Chekin Bay, 1.vii.1901, Timofeev (1 ♂, 1 ♀, ZIN); Matochkin Shar, radio station, 8.vii.1924, Tolmachow (1 ♀, ZIN). Chukotka AO (Wrangel Island) : Somnitelnaya Bay, on flowers of Papaver, 18.vii.1966, KBG (1 ♀, ZIN); same locality, on flowers of Dryas integrifolia, spotted tundra, 19.vii.1966, KBG (8 ♂, 11 ♀, ZIN; 1 ♂, 1 ♀, CNC); same locality, sea shore at midnight on flowers of Papaver polaris, 25.vii.1966, KBG (5 ♂, 3 ♀, ZIN); same locality, on flowers of Potentilla emarginata, 26.vii.1966, KBG (3 ♀, ZIN); same locality, spotted tundra near village, 9.vii.1972, KBG (5 ♂, 7 ♀, ZIN); 5 km N Somnitelnaya Bay, 28.vii.1971, KBG (1 ♂, 1 ♀, ZIN); Somnitelnaya Bay, valley of river Somnitelnaya, southern slope of Mineev Mtn, 100 m, shingle, 26.vii.1966, KBG (3 ♀, ZIN); environs of Somnitelnaya Bay, valley of river Somnitelnaya, Mineev Mtns, 150 m, shingle, on flower of Dryas integrifolia, 22.vii.1966, KBG (1 ♂, ZIN); Somnitelnaya River, 71°00′N 179°32′W, BT 9 ВG, 14.vii.2006, OAK (1 ♂, 1 ♀, ZIN); same locality and biotope, 18.vii.2015, OAK (1 ♀, ZIN) environs of Tundrovaya Mtn, near stream, 18.vii.1972, KBG (1 ♂, 2 ♀, ZIN); middle flow of Mamontovaya River, N Perkatkun, osier-bed in valley of river, 17.vii.1972, KBG (2 ♂, 1 ♀, ZIN); same locality, 71°10′N 179°45′W, Arctic fox burrow, 11.vii.2006, OAK (2 ♂, 2 ♀, ZIN); same locality and biotope, 11–21.vii.2006, OAK (1 ♂, ZIN); same locality and biotope, 1.vii.2015, OAK (1 ♂, ZIN); same locality, BT 6, 9.vii.2006, OAK (2 ♂, 1 ♀, ZIN); same locality, BT 5 А, 20.vii.2006, OAK (3 ♂, 15 ♀, ZIN); same locality, BT 5, 30.vi.2015, OAK (3 ♂, 10 ♀, ZIN); same locality, BT 10, 8.vii.2006, OAK (4 ♂, 3 ♀, ZIN); same locality and biotope, 30.vi.2015, OAK (2 ♂, ZIN); same locality, BT 17, 3.vii.2015, OAK (2 ♂, 1 ♀, ZIN); same locality, BT 1 А, YPT, 2–4.vii.2015, OAK (1 ♂, ZIN); same locality, house, 30.vi.2015, OAK (1 ♀, ZIN); spurs of Pervaya Mtn, 71°09′N 179°27′W, BT 13, 28.vi.2015, OAK (2 ♂, 8 ♀, ZIN); same locality and biotope, 28.vi.–13.vii.2015, OAK (2 ♀, ZIN); same locality, BT 15, 28.vi.2015, OAK (1 ♂, 1 ♀, ZIN); same locality and biotope, 28.vi.–13.vii.2015, OAK (1 ♀, ZIN); upper flow of Neizvestnaya River, 71°13′N 179°19′W, BT C4, 3.vii.2006, OAK (11 ♀, ZIN); same locality and biotope, 12–29.vii.2015, OAK (1 ♀, ZIN); same locality, BT С2, 21.vi.2015, OAK (2 ♀, ZIN); same locality, BT С3, 21.vi.2015, OAK (2 ♀, ZIN); same locality, BT 10 А, 22.vi.2015, OAK (1 ♂, ZIN).

Diagnosis. Mid-sized (wing length 4.5–5.3 mm) blackish flies. Male holoptic; body black setose; scutum greyish brown pruinescent, without vittae; acr biserial, presutural dc 3–4-serial; hind tibia curved inward closer to base, hind basitarsus expanded, nearly as broad as apex of hind tibia; halter with yellow knob; CuA+CuP complete; phallus well exposed, long, with narrow U-shaped loop just beyond cerci. Female mid and hind femora with anterodorsal and posteroventral rows of pennate setae (except extreme base); hind tibia with some subpennate setae dorsally and ventrally.

Redescription. Body length 4.6–5.5; wing length 4.5–5.3 mm. Male (Fig. 66, described for first time). Head with greyish brown pruinescence on face, frons, postgena, ocellar triangle and occiput; dark setose. Holoptic; upper ommatidia enlarged. Frons represented by very small subtriangular space below ocellar tubercle and larger subtriangular space above antennae, with scattered marginal setulae; with single setulae or bare. Face broad, bare. Ocellar triangle with 2 long and several short fine setae. Occiput with numerous long thin setae, including postoculars; postgena with numerous finer setae than occiput. Antenna blackish brown; scape and pedicel short, scape slightly longer, both with short setulae; postpedicel conical, slightly concave on apical part ventrally, nearly 2.5–3X longer than wide; stylus rather long, 1.3–1.5X shorter than postpedicel. Palpus dark; with long, dark fine setae. Proboscis with labrum dark reddish-brown, 1.3–1.5X head height.

Thorax dark in ground-colour, greyish brown pruinescent; with black setation; scutum greyish brown pruinescent, somewhat lustrous, without vittae. Proepisternum with tuft of numerous long setae on lower section; upper proepisternum in front of spiracle without setae. Prosternum bare. Antepronotum with numerous short setae. Postpronotal lobe usually with 2 long, stronger and several short fine setae (sometimes with additional long fine setae). Mesonotal setation (number, robustness and position of main mesonotal setae very variable, often even on right and left sides): several long fine setae on supra-alar space (psut spal more numerous), 3–5 npl (additional fine setae anteriorly), 1 long and 1 short pal, 6–8 sctl (often with additional short fine setae); acr long, thin, arranged in 2 irregular rows, absent on prescutellar depression; presutural dc long, arranged in 3–4 irregular rows, postsuturals 1–2-serial, 3–4 prescutellars longest. Laterotergite with numerous long fine setae. Anterior and posterior spiracles brown.

Legs uniformly dark brown; mostly subshiny, coxae and trochanters with denser greyish pruinescence; black setose. Fore coxa covered with long fine setae anteriorly. Femora and tibiae slender; hind femur only slightly thicker than fore and mid femora; hind tibia curved inward closer to base (posterior view); hind basitarsus thickened, nearly as broad as hind tibia at apex. Mid and hind femora whitish pilose ventrally; fore femur with rows of fine, long anteroventral and posteroventral setae (nearly as long as femur width) and similar setae anteriorly; mid femur with rows of short fine anteroventral and long posteroventral setae; hind femur with complete row of rather long fine anteroventral setae. Fore tibia with 2–3 short anterodorsal and long fine setae posterodorsally; mid tibia with 3–4 anterodorsal and 3–4 posterodorsal setae (except circlet of subapicals) becoming longer toward apex of tibia (longest setae nearly 1.5X longer than tibia width), several short spine-like anteroventral and posteroventral setae on about apical half. Hind tibia with numerous long anteroventral and posteroventral setae, lacking setulae on concave space near base; 1 seta in posteroapical comb of hind tibia. Fore basitarsus with somewhat longer setae dorsally (nearly as long as basitarsus width); mid and hind basitarsi with numerous long setae dorsally (longest setae nearly twice longer that corresponding basitarsus width).

Wing membrane faintly brownish, mostly with brownish veins; all veins complete (except Sc); CuA+CuP (anal vein) weakened on subapical portion. Pterostigma brownish yellow; 1 basal costa seta present, short. Anal lobe welldeveloped; axillary incision almost 90°. Squama brownish, dark fringed. Halter with yellow knob and brownish yellow stem.

Abdomen dark brown, faintly brownish pruinescent, subshiny; covered with uniform black fine setae shorter on tergites dorsally, sternite 8 with numerous very long posteromarginal setae. Segments 6–7 with unmodified vestiture and structure. Segment 8 with tergite and sternite separated, both normally sclerotized; tergite 8 concave posteromedially; sternite 8 unmodified, subrectangular viewed laterally, nearly as long as sternite 7.

Terminalia dark brown (Fig. 67). Cerci directed posteriorly, separated from each other and from epandrium; covered with numerous fine dark setulae dorsally, numerous spinule-like setae along lower margin; cercus subrectangular (lateral view), with tapered apex, about as long as epandrium and half as broad as epandrium; without pair of subepandrial lobes beneath. Epandrium subrectangular, broadly rounded apically; shiny on basal region; covered with long, fine dark setae. Hypandrium mostly membraneous, only lateral arms sclerotized, bare. Phallus yellowish to brownish yellow, well exposed; evenly curved and uniformly slightly broader on about basal half until lower margin of epandrium, tapered apically; slightly curved between cerci, with narrow U-shaped loop just beyond cerci. Ejaculatory apodeme not extended beyond basal curvature of phallus, with narrow lateral wings and without prominent vertical wing.

Female. Similar to male, except face broad with lateral setulae; mid and hind femora with anterodorsal and posteroventral rows of pennate setae (except extreme base); hind tibia with some subpennate setae dorsally and ventrally. Cercus long slender, covered with dark setulae.

Remarks. The male was associated with the female after a pair taken in copula, which was found among material collected from the type locality. The female was compared with the syntypes housed in ZIN.

Frey (1950) placed R. taimyrensis in his subgenus Dasyrhamphomyia, but this is not confirmed by our discovery of a male of this species. Actually, R. taimyrensis is most closely related to R. laevigata Loew, revised very recently by Sinclair et al. (2019), which is widely distributed in North America and also was known for a long time from the extreme north of Russia as R. fridolini Frey. The subgeneric position of these species remains unclear.

Distribution. Palaearctic; R. taimyrensis is broadly distributed across the Russian Arctic including continental areas and islands (Novaya Zemlya Archipelago, Wrangel).

Habitat. On Wrangel Island, this species was not found in the colder region (Neozhidannaya River), but in one year (1966) it was numerous in the coastal spotted tundra. In the 2000s, this species was collected mainly in the warmer central region of the island, in dry habitats, especially often in tundra-steppe-like vegetation.

Unnamed species of Rhamphomyia