Bicellaria chimganensis, Barták, Miroslav, Plant, Adrian & Kubík, Štěpán, 2013

Barták, Miroslav, Plant, Adrian & Kubík, Štěpán, 2013, Species of Bicellaria (Diptera: Hybotidae) from Asia, Zootaxa 3710 (3), pp. 233-256 : 236-237

Bicellaria chimganensis sp. nov.

( Figs 3, 4 )

Type material. HOLOTYPE ♂, Uzbekistan, Chimgan, damp valley, 1200 m, 41.38 N, 70.02 E, 18.v.1989, M. Barták (CULSP). PARATYPES: Uzbekistan: 12♂, 42♀, same data as holotype; 1♂, 1♀, same locality as holotype, except 1800 m, 41.38 N, 70.06 E; 8♂, 4♀, Aktash, deciduous wood, 500 m, 41.38 N, 69.46 E, 17.v.1989; 1♀, Karamazar, damp meadow, 500 m, 41.32 N, 69.48 E, 18.v.1989; 1♀, same locality, 800 m, 41.30 N, 69.49 E— M. Barták—(CULSP).

Diagnosis. Nearly all setae including acrostichals, dorsocentrals and those on legs pale (white to brownish yellow); halter yellow in both sexes; third antennal segment without elongate dorsal setae; hind basitarsus narrow and hind tibia swollen in both sexes. Male hypandrial processes narrow; only one (left) long phallic hook present; female tergites 5–8 and sternites 6–8 polished.

Etymology. The species is named after type locality (Chimgan Mountain in Uzbekistan).

Description. Male. Head brownish-black, rather light grey microtrichose, pale setose. Holoptic, facets in dorsal half much larger than in ventral half, about 11–13 facets in line of contiguity of eyes. One pair of rather long ocellar setae. Face slightly narrowed ventrally, ventral part about 0.03–0.04 mm broad at narrowest point. Clypeus slightly paler grey microtrichose. Palpus short, brown, with 3 setae. Labrum short, brown, polished. Antenna black, 2nd segment short setose (longest setae about 0.08 mm); 3rd segment without elongate dorsal setae; ratio of broad part of segment 3: narrow part of segment 3: arista (at 0.01 mm resolution) = 12–16: 5–7: 16–20. Thorax brownish-black, rather sparsely light grey microtrichose, mesoscutum almost subshining in dorsal view, prescutellar area differently microtrichose than other parts of mesoscutum, appearing light grey. All thoracic setae pale. Chaetotaxy: 6–9 broadly biserial acrostichals; 7–13 uniserial dorsocentrals (both acrostichals and dorsocentrals about 0.10 mm long before suture); about 6–9 setae in intrahumeral and posthumeral areas; 1–2 long and 1–2 shorter postpronotals; notopleuron with 3–6 setae arranged in one irregular row; 1 supraalar and 1 prealar; 1 long postalar; 2 pairs of scutellars. Legs including coxae blackish brown, microtrichose and pale setose, tarsi with darker setae. Fore femur short setose, both anteroventrals and posteroventrals much shorter than depth of femur (except preapicals). Fore tibia with 4–5 posterodorsals up to 2X longer than depth of tibia, otherwise short setose, posteroventrals in apical third about as long as depth of tibia, pilosity apparently absent (similar to B. spuria ). Mid femur with sparse row of anteroventrals one-third as long as depth of femur and with somewhat longer posteroventrals slightly shorter than depth of femur. Mid tibia with 1–2 pairs of setae dorsally in basal half up to twice as long as depth of tibia, otherwise short setose. Hind femur with 15–20 anterodorsal setae on basal third up to 2X as long as depth of femur, much shorter apically and with row of 16–22 anteroventrals slightly longer than depth of femur at about middle and shorter both basally and apically, posteroventrals half as long as depth of femur. Hind tibia swollen in apical part (0.14–0.16 mm at broadest point in comparison with 0.06 mm in basal part), several anterodorsals and posterodorsals up to 0.20 mm long, ventral setae short. Tarsi of all legs thin, short setose, basitarsus of hind leg very slightly swollen (0.09 mm). Wing slightly yellow-brownish infuscated; stigma brown, long (0.70 mm), almost parallel-sided and narrow (0.05 mm), narrower than cell r1 (about 0.09 mm broad at narrowest point). Distance between tips of veins R1 and R2+3 about 0.30 mm. Squama yellowish with pale fringes, halter clear yellow. Abdomen blackish-brown in ground-colour, brown in dorsal view and pale grey in lateral view, microtrichose, pale setose, dorsally with short setae, posteromarginals on sides of tergites as long as or slightly longer than corresponding segments. Genitalia ( Figs 3, 4 ) with hypandrial processes medium long and narrow, with conspicuous but not very long spine at tip; postgonites elongate-trapezoid, slightly asymmetrical (right one slightly longer and broader at apex); left phallic hook long, right one strongly reduced. Female mesoscutal setae less numerous and hind tibia narrower (0.11 mm) than in male. Tergites 5–8 polished, sternites 5–8 polished (5th sternite with narrow sparsely microtrichose central stripe), other parts of abdomen microtrichose. Length: body 2.2–3.0 mm, wing 2.3–3.0 mm.

Remarks. Bicellaria chimganensis sp. nov. can be easily recognized from all other Palaearctic species of Bicellaria by its mostly pale setose body (including all mesoscutal setae) and narrow hind basitarsus. Moreover, females have the last four sternites polished. Bicellaria amankutanensis sp. nov. is undoubtedly closely allied with this species. Beside the main diagnostic character given in the key (different colouring of mesoscutal setae), the species described above has slightly smaller broad part of third antennal segment, less setae on the intrahumeral and posthumeral areas and more sparsely microtrichose mesoscutum giving it a subshining appearance. The genitalia of both species are very similar, B. chimganensis sp. nov. has slightly narrower hypandrial processes. Female 5th sternite is polished in B. chimganensis sp. nov. with the exception of sparsely microtrichose central stripe but is densely microtrichose (with the exception of narrow polished lateral parts) in B. amankutanensis sp. nov.

Figures

FIGURES 1 – 8. Hypandrium (ventral view) and phallus with postgonites (lateral view). 1 – 2. Bicellaria amankutanensis sp. nov. 3 – 4. B. chimganensis sp. nov. 5 – 6. B. farkaci sp. nov. 7 – 8. B. femorata Collin. Scale bars = 0.10 mm.