Dolichopus tumicosta Negrobov, Grichanov et Barkalov, sp. nov.

Dolichopus tumicosta Negrobov, Grichanov et Barkalov sp. nov.

(Figs. 1–3)

Type material. Holotype 3: Russia: Republic of Altai, Kosh-Agach district, at the foot of Teplyi Klyuch Pass, «Radonovyi istochnik» [radon spring], 2412 m, 49.46ºN, 88.05ºE, 5.VII.2008, Coll. A. Barkalov [SZM]. Paratypes: Russia: 23, 2♀ with same data as holotype; 123, 3♀, Republic of Altai, Kosh-Agach distr., Plateau Ukok, 2400 m, 49.26ºN, 87.65ºE, 8–11.VII.2008, Coll. A. Barkalov / sweeping on sedge along lake bank; 13, 1♀, Republic of Altai, Kosh-Agach district river, Plateau Ukok, 2228 m, Muzdy-Bulak Lake, 49.23ºN, 87.78ºE, 25.VI.2005, Coll. V. Sorokina; 103, 2♀, Republic of Altai, Plateau Ukok, Lake Muzdy- Bulak env., 2400 m, 49.26ºN, 87.65ºE, 8-10.VII.2008, Coll. A. Barkalov; 23, Altai, Plateau Ukok, Ak- Alakha River Valley, 49.25ºN, 87.37ºE, h-2160, 13.VII.2006, Coll. V. Sorokina [SZM, ZIN, VSU].

Diagnosis. This species keys to D. pamiricus Negrobov (see key above). Legs entirely black; clypeus ending at lower eye margin; palpus dark; proboscis short; fore coxa with pale setae; hind femur with 1 anterior preapical seta; costa with long large thickening at R1; lower calypter with yellow-white cilia.

Description. Male: Body length: 3.9-4.7 mm, wing length: 3.7-4.3 mm, wing width: 1.8 mm, antenna length: 1.3 mm, hypopygium length: 1.5 mm.

Head: Face silvery-white, reaching lower eye margin, in middle about as wide as postpedicel height. Proboscis and palpus dark-brown, with black hairs; palpus whitish pollinose. Frons shining, metallic greenblack. Antenna (Fig. 1) black; scape long, 2 times longer than high, with row of dense black dorso-lateral setae. Pedicel hardly longer than high, with ring of small apical setae; postpedicel bud-like, with pointed apex, hardly longer than high; stylus bisegmented, short, about as long as scape, pedicel and postpedicel combined, shortly haired, simple, middorsal. Lower postocular setae white. Thorax: metallic green-black; pleura weakly grey pollinose; proepisternum with 1 strong black seta and small white hairs. Legs: black; pulvilli white. Coxae with white hairs; fore and mid coxae with black apical setae; hind coxa with 1 strong black seta at middle. Femora without long ventral setae. Mid and hind femora with 1 strong anterior preapical seta; mid femur with small posterior preapical seta. Fore tibia with 3 anterodorsal and 1–2 posterior setae, 1 fine long yellow apicoventral seta. Mid tibia with 3 antero- and 2 posterodorsal setae, 1 anteroventral seta. Hind tibia inconspicuously thickened in basal half, with 3-4 anterodorsal, 2 dorsal, 1 ventral setae, with small posterior apical tooth. All tarsi simple. Pulvilli and claws small. Hind basitarsus with 1 strong dorsal, 1–2 shorter anterior setae, with or without 1 short ventral seta. Tarsomere length ratio: fore tarsus (from first to fifth): 22/ 10/8 /6/6, mid tarsus: 35/16/12 /10/9, hind tarsus: 32/ 30/18/11 /10. Wing: hyaline or weakly smoky, widely rounded at apex. Costa with long large thickening at R1, thickening longer than R1. R4+5 and M1+2 parallel at apex. M1+2 with strong curvation just before middle of distal part. Distal part of CuA1 longer than m-cu. Hind margin of wing evenly convex. Lower calypter yellow, with yellow-white cilia. Halter yellow. Abdomen: metallic green-black or bronze-green, shining, with black setae. Hypopygium relatively small, brown. Apicoventral epandrial lobe brown, broad, rounded at apex, with 1 strong seta and some fine setulae. Surstyli brown. Cercus nearly rounded, serrate at apex, with mainly simple setae and setulae, with hooked dorsoapical setae at margin, dirty grey, darker along distal margin.

Female: Body length: 4.1-4.3 mm, wing length: 4.0- 4.3 mm; similar to male except lacking male secondary sexual characters; face wider; lower calypter with black cilia; abdomen with white ventral setulae.

Distribution. Dolichopus tumicosta is only known from the high-mountain locality in Altai Mountains, i.e. from the Plateau (Table) Ukok. All specimens were collected in high-mountain tundra on sedge near small lakes or along streams.

Etymology. Lat. tumere, costa: 'with swollen wing costal vein'.