Empis (Polyblepharis) yakovlevi Shamshev 2019, sp. nov.

Empis (Polyblepharis) yakovlevi sp. nov.

(Figs 10–12)

Holotype. Male, Russia, Republic of Altai, “[in Cyrillic, Russian] Tashanta 4 km E [~ 49°43'N 89°11'E] / south-eastern Altai / V. Richter 6 vii [1]977”, “ Empis (Polyblepharis) yakovlevi Shamshev, sp. n. [red label]” (ZIN, INS _DIP_0000725).

Paratypes. Same data as for holotype: 15 males, 2 females, 6.VII.1977; 1 male, 1 female, 7.VII.1977; 1 female, 15.VII.1977. Russia, Republic of Altai: 2 males, 4 females, Chikhachev ridge, pass, 24.VII.1964, E. Nartshuk leg. (all ZIN); 13 males, 8 females, Kosh-Agach distr., plateau Ukok, 2450 m, Muzdy-Bulak Lake, 49.3°N 87.65°E, 8–12.VII.2008, A. Barkalov & V. Sorokina leg. (SZMN); 12 males, 5 females, plateau Ukok, Kaljin-Kul-Bas and Kaljin-Kul lakes, 49°19'N 87°26'E, 2400–2450 m, 17–20.VII.2006, V. Sorokina & T. Novgorodova leg. (SZMN); 2 males, plateau Ukok, 8 km NE of Maytobe, 49°34'N 87°43'E, 2400–2500 m, 8.VII.2006, V. Sorokina leg. (SZMN); 1 male, 2 females, 8 km NE of Maytobe, tributary of Ildegem River, 49°34'N 87°43'E, 2500 m, 10.VII.2006, T. Novgorodova leg. (SZMN); 1 male, Ust’-Koksa distr., Katunskiy ridge, Kamdyt, 49°58.7–49.14'N 86°33–34.9'E, 2150–2514 m, subalpine-alpine [zone], 28. VI –4.VII.2007, O. Kosterin leg. (ZMUM).

Diagnosis. Large species (body length about 8 mm) with extensively yellow legs almost entirely covered with long dense hair-like setae, face bearing marginal setae, palpus black, scutum with four vittae, laterotergite with black setae, abdominal tergites extensively shiny. Male: eyes almost touching on frons, tarsomeres of fore and mid tarsi somewhat thickened. Female: legs not pinnate.

Description. Male (Fig. 10). Body length 7.6–8.1 mm (holotype, 7.9 mm); wing length 7.1– 7.4 mm (holotype, 7.3 mm).

Head black, with black setation. Eyes dichoptic, ommatidia of equal size. Frons very narrow in upper part, at most as broad as anterior ocellus, widened above antennae, densely brownish pruinose, bare. Face wide, almost parallel-sided, largely brownish grey pruinose, narrowly shiny along lower margin, with 3–4 black marginal setae in upper part; clypeus shiny. Occiput densely greyish pruinose, covered with dense, long, thin setae. Ocellar tubercle concolorous with occiput, with numerous similar setae. Antenna black; scape about 1.5 times as long as pedicel, with black setulae longer than in pedicel; postpedicel moderately long, nearly 3 times as long as wide, with straight margins; stylus about half the postpedicel length. Proboscis moderately long; labrum brownish, 1.3–1.5 times as long as head height; palpus long, black, with numerous very long black setae.

Thorax black, densely brownish grey pruinose (except as noted); scutum with four indistinct, broad, brownish vittae (in dorsal view); setation black. Prosternum bare. Proepisternum and antepronotum with numerous uniform long hair-like setae. Postpronotal lobe shiny on outer side, with numerous moderately long to long subequally thin setae. Mesonotal setation: presutural and postsutural surfaces with numerous long setae of different robustness (2–3 setae usually stronger but highly variable), 4–6 long notopleurals (number and position highly variable, often even on right and left sides; additional long thin setae present on anterior part of notopleuron), 1–2 very long and 1–2 short postalars, numerous scutellars of different robustness (number and position highly variable; at least 7 setae present on each side); acrostichals long, thin, numerous, arranged in 2–3 irregular rows, lacking on prescutellar depression; dorsocentrals arranged in 3–5 irregular dense rows before suture and in 2–3-serial sparser rows toward scutellum, somewhat longer than acrostichals, of subequal length and robustness throughout (some prescutellars somewhat longer and stronger). Laterotergite with numerous setae. Anterior and posterior spiracles yellow.

Legs with coxae and trochanters black, faintly greyish pruinose; femora and tibiae extensively yellowish, very narrowly brownish at apices (in paler specimens, femora entirely yellowish); tarsi almost uniformly brownish, basitarsi somewhat paler near base. All parts of legs with black setation; coxae and trochanters with numerous long setae. Fore and mid tibiae and tarsi somewhat thickened; hind femur slender, only slightly broader than fore and mid femora. All femora entirely covered with long thin setae; also, hind femur with some stronger anteroventral setae in subapical part. Fore and mid tibiae with similar but denser and longer setae (especially dorsally) spreading on to corresponding tarsomeres 1–4; both without strong setae (except circlets of subapicals). Hind tibia with shorter thin setae than on preceding tibiae, also bearing 5–6 anterodorsal and 5–6 posterodorsal short stronger setae (besides circlet of subapicals); posteroapical comb with one moderately long, strong seta. Hind basitarsus with sparser and somewhat shorter setation dorsally; tarsomeres 2–5 with simple setulae.

Wing membrane brownish infuscate. Pterostigma brownish yellow, narrow. Basal costal seta moderately long. Veins R 5 and M 1 divergent in subapical parts; radial fork acute. Anal angle acute, subsequently anal lobe well-developed. Calypter brownish, dark fringed. Halter yellow.

Abdomen entirely black, with tergites (except hidden tergite 8) almost entirely shiny; tergites 1 and 2 narrowly brownish grey pruinose anteriorly, tergites 6 and 7 with brownish iridescent spots; sternites 1–2 entirely brownish grey pruinose, remaining sternites narrowly pruinose anteriorly. Abdomen covered with uniform, long, dense, black setae, without stronger posteromarginal setae. Sclerites of segment 7 unmodified; tergite 8 separated from sternite 8, divided medially, represented by two subtriangular sclerites bearing scattered setulae; sternite 8 large, scoop-shaped, with three tubercles near base laterally on either side. Terminalia (Fig. 11) moderately large, dark brown, only phallus brownish yellow. Cercus elongate oval (in lateral view), with smoothed inner margins (in dorsal view), covered with black setulae. Epandrial lamella rather subrectangular (in lateral view), covered with black setulae being somewhat longer along lower margin. Hypandrium subtriangular in ventral view, bare. Phallus (Fig. 12) divided; apical part of distiphallus hooklike, very slender, moderately long.

Female. Body length 6.4–6.8 mm; wing length 6.9–7.4 mm. Similar to male, except the following characters. Frons broad, parallel-sided, with marginal setulae; occiput with sparse setae; thorax and legs with similar but shorter setation; fore and mid tarsomeres slender; abdomen with scattered short setae, posterior part of tergite 2 and entire tergites 3–8 shiny, sternites 6–8 subshiny. Cercus slender, moderately long, covered with dark setulae.

Comparison. The new species is most similar to E. hirsuta Becker, 1915 known only from the North Urals (Shamshev, 2016). Empis yakovlevi sp. nov. differs from E. hirsuta primarily in the black palpus (versus yellow) and the longer setae on the femora; also, the male has evenly thickened fore tibia (vs. clavate).

Etymology. The new species is named in honour of Russian entomologist Roman V. Yakovlev (Barnaul) in recognition of his contribution to the knowledge of insects of Altai.

Distribution. Palaearctic: Russia (Republic of Altai).

Habitat and seasonal occurrence. According to the label data, the species occurs in subalpine and alpine zones (2100–2500 m). It was collected from late June until late July.

A key to species of Polyblepharis of the Altai region of Russia

1. Scutum (in dorsal view) with three indistinct vittae running beneath the rows of acrostichal and dorsocentral setae or without vittae............ 2

– Scutum (in dorsal view) with four distinct brownish, dark or shiny vittae (one between the rows of acrostichals and dorsocentrals and one between the dorsocentrals and supra-alars on either side).... 3

2. Acrostichal and dorsocentral setae multiserial, long. Male: fore basitarsus about half the fore tibia length. Female: palpus largely yellow, darkened at apex........................ E. (P.) sedelnikovi

– Acrostichal setae biserial, dorsocentrals arranged in one to two irregular rows, very short. Male: fore basitarsus at least two-thirds the fore tibia length. Female: palpus black......... E. (P.) longimana

3. Palpus black................................. 4

– Palpus yellowish............................. 6

4. Smaller, body length about 4 mm; scutum with shiny blackish vittae; legs entirely black................................. E. (P.) altaica sp. nov.

– Larger, body length 8–9 mm; scutum with dull brownish vittae; legs extensively yellow........ 5

5. Face bare; frons broad, only slightly narrower than the distance between outer margins of posterior ocelli; fore and mid tarsomeres slender; legs covered with short setae; tibiae black. Female unknown................... E. (P.) seminskiensis sp. nov.

– Face with marginal setae; frons narrow, eyes almost touching; fore and mid tarsomeres somewhat thickened; legs almost entirely covered with long dense hair-like setae; tibiae extensively yellowish........................... E. (P.) yakovlevi sp. nov.

6. Acrostichal setae biserial, dorsocentrals usually biserial anteriorly and uniserial toward scutellum; scutellum with 4–6 setae; laterotergite mostly with black setae................................... 7

– Acrostichal setae arranged at least in three to four irregular rows, dorsocentrals multiserial anteriorly; scutellum at least with 10 setae; laterotergite with pale to yellowish setae........................ 8

7. Postpronotal lobe shiny on outer side. Male: eyes holoptic. Female: mid and hind femora with short posteroventral pennate setae.. E. (P.) subciliata

– Postpronotal lobe entirely pruinose. Male: eyes dichoptic, separated by broad frons. Female unknown.................. E. (P.) turalae sp. nov.

8. Hind femur thickened, with numerous spine-like setae throughout ventrally; hind tibia slightly thickened toward apex; hind femur about 1.5 times as wide as hind tibia in middle part; legs usually uniformly brownish............. E. (P.) crassa

– Hind femur slender, covered only with simple setulae ventrally, at most with 3–4 short anteroventral setae in subapical part; hind tibia almost evenly thickened, in middle part nearly as wide as hind femur; mid and hind femora usually yellowish (except extreme apex)................. E. (P.) gravipes