Rhamphomyia (Pararhamphomyia) armipes Sack

Shamshev, Igor V., Sinclair, Bradley J. & Khruleva, Olga A., 2020, The empidoid flies (Diptera: Empidoidea, exclusive of Dolichopodidae) of the Russian Arctic islands and Svalbard Archipelago, Zootaxa 4848 (1), pp. 1-75 : 29-31

Rhamphomyia (Pararhamphomyia) armipes Sack

( Figs 28–31 )

Rhamphomyia armipes Sack, 1923: 6 . Type-locality: Novaya Zemlya (Krestovy Island), Arkhangelskaya Province, Russia.

Other references: Melander, 1928: 382 (catalogue); Frey, 1955a: 469 (revision); Gorodkov & Kovalev, 1969: 624 (key); Chvála & Wagner, 1989: 297 (catalogue); Shamshev, 2001b: 325 (key); Yang et al., 2007: 168 (catalogue); Shamshev, 2016: 61 (checklist).

Type material examined. LECTOTYPE (here designated in order to fix identity of the species) ♂ ( Fig. 28 ), labelled ( Fig. 29 ): “ Typus [blue label]”; “Novaj. Semlja. Ökland/ Østre Korsä / ( Achaugel bűgt.)/ No 224/ 15 aűg.”; “ Rhamphomyia / armipes Sack / nov. spec.”; “Gl.1695/ ZM. Oslo ”; “pinx [pink label]”; “ Typus [pink label]”; “ NHMO: type collection/ 1000327600”; “ NHMO / Norway [data matrix code]”; “ LECTOTYPE / Rhamphomyia / armipes Sack / des. Sinclair 2020 [red label]” ( NHMO).

PARALECTOTYPE: Berek (Briska) Ösla [?], 18 Aug. No. 235 (1 ♀, NHMO) .

Note on types. This species was originally described on the basis of one male and two female specimens.

Diagnosis. This dark, shiny-legged and pale brown setose species is distinguished from other Pararhamphomyia by the male hind femur and tibia with triangular projections and apex of subepandrial lobe pointed. Female legs without pennate setae.

Redescription. Wing length 4.5–5.5 mm. Male ( Fig. 28 ). Head with greyish pruinescence on face, frons, postgena and occiput. Holoptic, eye 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 slightly divergent towards mouthparts; bare, with narrow oral margin shiny. Ocellar triangle dark, pruinescent, cellar setae broken; 2–3 pairs of postocellar setae slightly shorter and finer than posterior ocellar setae. Occiput with rows of dark, long, curved postocular setae; postgena with finer, sinuous setae than occiput. Antenna dark brown; scape and pedicel of equal lengths; postpedicel broken off. Palpus dark, with long, dark setae. Clypeus with greyish pruinescence; labrum lustrous and dark reddish-brown, 1.5X head height; labellum dark and bearing dark setulae.

Thorax dark in ground-colour, largely densely grey pruinescent; setae long, fine, brownish. Scutum with 2 indistinct, dark grey vittae between acr and dc rows. Pleura clothed in grey pruinescence. Proepisternum with several long, dark setae on lower section; upper proepisternum in front of spiracle with several long, dark setae; prosternum bare.Antepronotum with row of short, stout dark setae. Postpronotum with numerous long setae. Scutum with biserial acr; dc multi-serial, subequal in length to acr, prescutellar setae longer, not differentiated from lateral setae; numerous undifferentiated presut spal; numerous undifferentiated npl; numerous prealar setae; 4 or more psut spal similar to prealars; 1 pal with several shorter setae; 4 pairs of sctl. Laterotergite with several long, dark setae. Anterior and posterior spiracles dark brown with outer black ring.

Legs dark reddish brown, shiny; coxae with faint greyish pruinescence. Coxae with dark setae. All femora with distinct white ventral pile; fore femur with anteroventral row of setae, with longer posterior setae; mid and hind femora with 1 anteroventral and 1 posteroventral row of setae, stronger than on fore femur, less than half corresponding femur width. Hind femur with triangular posteroventral projection beyond mid-length. Fore tibia and tarsomere lost. Mid tibia with long, erect setae; posterior setae twice as long than anterior setae; with posteroventral row of strong setae, longer than tibial width. Hind tibia ( Fig. 30 ) with triangular posteroventral projection on basal third and long posterodorsal setae; 1 long seta in posteroapical comb. Hind tarsomere 1 similar in size to apical width of hind tibia, dorsal setae shorter than tibial setae; with dense, dark, stout ventral setae.

Wing lightly infuscate with brown veins; all veins complete (except Sc); CuA+CuP at apical fourth extended to wing margin as faint fold. Pterostigma brownish; basal costa seta absent; anal lobe well-developed. Axillary incision right angle. Halter dark brown.

Abdomen dark brown with greyish pruinescence; covered with long, pale brown setae laterally, shorter on tergites dorsally. Tergite 8 similar in length to tergite 7.

Terminalia ( Fig. 31 , undissected): Epandrium strongly tapered apically; long setae on apical half dorsally and ventrally. Cercus with broad base, tapered, shorter than subepandrial lobe [right cercus broken at base]. Subepandrial lobe cylindrical, with pointed apex; clothed in pruinescence.Hypandrium not visible.Phallus with swollen cylindrical base; lustrous and reddish brown, not forming loops, gently arched between epandrial lamellae [apex not visible].

Female. Similar to male, except basal costa seta present; postoccipital setae stronger; thoracic setae stronger, more differentiated, with more numerous sctl; mid tibia slightly arched, distinctly shorter than femur, with 1 anteroventral and 1 posteroventral row of short, strong setae; without pennate setae; CuA+CuP strong to wing margin.

Remarks. Sack (1923) included illustrations of the male hindleg and male terminalia, the latter upside down. The basal costal seta is apparently absent in the male lectotype, but is present in the female. Certain features of the female (presence of basal costal seta; strong CuA+CuP, midleg chaetotaxy) suggest that the female paralectotype is not conspecific with the male lectotype. Further collections of both sexes of this species are required for confirmation.

The cylindrical subepandrial lobe with pointed apex is similar in form to that of R. hoeli .

Distribution. This species is known only after the type series collected from Novaya Zemlya Archipelago (Krestovy Island, Serebryanka Fjord, Berkh Island).

Figures

FIGURES 28–31. Rhamphomyia (Pararhamphomyia) armipes Sack. 28. male habitus, lectotype, lateral view; 29. lectotype labels; 30. male hind leg, lectotype, anterior view; 31. male terminalia, lectotype, lateral view. Abbreviations: ph—phallus; sbepand lb—subepandrial lobe.