Rhamphomyia (Pararhamphomyia) subfilicauda Shamshev & Sinclair, 2020

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 : 39-41

Rhamphomyia (Pararhamphomyia) subfilicauda Shamshev & Sinclair sp. nov.

( Figs 41, 42 )

urn:lsid:zoobank.org:act:27AE8916-35F9-42A2-BD16-692DADF550F9

Type material. HOLOTYPE ♂, labelled: [ RUSSIA, Chukotka AO ( Wrangel Island )] “upper flow of river Neizvestnaya, 71°13′N 179°19′W, BT 2 , 3.vii.2006, O.A. Khruleva ”; “ Holotypus / Rhamphomyia / subfilicauda / Shamshev, Sinclair sp. n. [red label]” (INS_DIP_0000621, ZIN; terminalia dissected, in microvial pinned with specimen).

Diagnosis. Mid-sized (wing length 4.3 mm) blackish flies of the R. pusilla group. Scutum uniformly velvety brown, without vittae; postpronotal lobe and mesonotum with numerous uniformly very long fine setae (including acr and dc), main mesonotal setae undifferentiated; hind tibia curved inwards closer to base; halter brownish; wing whitish, CuA+CuP complete; phallus well exposed, very long, mostly hair-like.

Description. Male ( Fig. 41 ). Wing 4.3 mm, body 4 mm. Head with brownish pruinescence on face, frons, postgena, ocellar triangle and occiput; dark setose. Eyes holoptic, touching on frons. Ocellar triangle with several long fine setae. Occiput with numerous uniformly long thin setae, including postoculars. Antenna blackish brown; scape and pedicel short, scape slightly longer, both with short setulae; postpedicel conical, 3X longer than wide; stylus very short, slightly shorter than postpedicel basal width. Palpus dark; with numerous long, dark fine setae. Labrum 1.3X head height.

Thorax densely brownish pruinescent; with black setation; scutum uniformly velvety brown pruinescent, without vittae. Proepisternum with tuft of several long fine setae on lower section; upper proepisternum in front of spiracle without setae. Prosternum bare. Antepronotum with numerous short setae. Postpronotal lobe and mesonotum with numerous uniformly very long fine setae (including acr and dc), main mesonotal setae undifferentiated; 6 sctl; acr arranged in 2 irregular rows, absent on prescutellar depression; presutural dc separated by bare space from supra-alars, arranged in 3–4 irregular rows, postsutural dc 1–2-serial. Laterotergite with numerous long fine setae. Anterior and posterior spiracles brown.

Legs rather robust; mid legs and hind tarsi missing, remaining parts uniformly dark brown, black setose. Fore basitarsus slightly expanded; hind tibia straight, evenly expanded towards apex. Fore femur with rows of moderately long, fine anteroventral (becoming longer toward base of femur) and mostly minute (3–4 moderately long setae near extreme base) posteroventral setae, some moderately long setae posteriorly; hind femur with moderately long to long (on about apical half of femur) setae anteroventrally, some moderately long setae anteriorly. Fore tibia with numerous long setae dorsally and posterodorsally (longest setae nearly 1.5X longer than tibia width); fore basitarsus with similar setae; hind tibia with numerous very long setae dorsally and similar setae anteroventrally (except extreme apex and base), 1 seta in posteroapical comb.

Wing membrane whitish; CuA+CuP (anal vein) incomplete; 1 basal costal seta present; axillary incision almost 90°. Squama brownish, dark fringed. Halter brownish.

Abdomen densely brownish grey pruinescent, covered with long black setae (shorter on tergites dorsally). Segments 6–7 with unmodified structure; tergite 6 covered with only scattered minute setulae; tergite 7 mostly with minute setulae, bearing several fine short setae posteromarginally and laterally. Segment 8 with tergite and sternite separated; tergite 8 simple, entire, subtriangular viewed laterally, very narrow mid-dorsally, broadly concave anteriorly, with almost straight posterior margin, numerous very long setae along posterior margin; sternite 8 simple, enlarged, subrectangular in lateral view, V-shaped viewed posteriorly, covered with numerous very long setae.

Terminalia ( Fig. 42 ) dark brown, black setose. Cerci separated from each other and from epandrium, not extended beyond tergite 8 anteriorly; cercus rather short, deeply cleft mid-dorsally and divided almost entirely into two parts: basal part subrectangular (lateral view), apical part rather elongate oval, both covered with short fine setae; without pair of subepandrial lobes beneath. Epandrium subtriangular, with strongly produced narrow apical part, slightly concave on upper margin, with more or less straight lower margin, extended far beyond cerci posteriorly; with row of 6 long fine closely set setae near upper anterior corner, cluster of short, very closely set spine-like setae on upper part slightly beyond middle, numerous long setae over lower margin becoming denser and stronger slightly beyond cluster of spine-like setae but short and scattered on remaining part of epandrium. Subepandrial sclerite produced slightly beyond lower margin of epandrium. Hypandrium very narrow, rim-like, entire, well sclerotized; bare; gonocoxal apodeme directed anteriorly. Phallus well exposed, very long; mostly hair-like, knob-like thickened just beyond hypandrium; slightly sinuate and with broad even curvature shortly beyond basal expansion, gently sinuate on remaining part. Ejaculatory apodeme not extended beyond basal curvature of phallus, with broad lateral wings and somewhat narrower vertical wing.

Female. Unknown.

Distribution. Eurasia; only Wrangel Island.

Etymology. The specific name refers to the similarity of the new species to R. filicauda Henriksen & Lundbeck.

Remarks. The new species belongs to the R. pusilla group sensu Barták & Kubík (2009) (see also Sinclair et al. 2019: 65). It is similar to R. filicauda Henriksen & Lundbeck , the main differences between these species have been provided in the key. In addition, the new species could be compared with R. aversa Frey known only from Tajikistan. However, R. aversa differs from the new species primarily by faintly infuscate wings (vs. whitish).

Habitat. The single specimen was collected in the moss-herb-dryad tundra in the warmer region of Wrangel Island.

Figures

FIGURES 41, 42. Rhamphomyia (Pararhamphomyia) subfilicauda sp. nov., male, holotype. 41. habitus, lateral view; 42. terminalia, lateral view. Abbreviations: cerc—cercus; ej apod—ejaculatory apodeme; epand—epandrium; hypd—hypandrium; ph—phallus.