Rhaphium beringiense Negrobov & Vockeroth

Rhaphium beringiense Negrobov & Vockeroth

(Figs. 2 F–G)

Rhaphium beringiense Negrobov & Vockeroth in Negrobov, 1979: 486.

Material examined. Russia: 7 3, 1 Ƥ, Taimyr Nature Reserve, Ary-Mas field station, left bank of river Novaya, 14 m a.s.l., inundated terrace, 72.5°N, 101.94°E, 10–12.VII.2010, Coll. A. Barkalov, yellow pan traps; 1 3, Republic of Altai, Kosh-Agach district, springhead of Naryn-Gol river, Kal’dzhinkul’ Lake, 2477 m a.s.l., 49.83°N, 89.44°E, 19.VII.2009, coll. A. Barkalov; 1 Ƥ, Republic of Altai, Kosh-Agach district, springhead of Naryn-Gol river, 2520 m a.s.l., 49.49°N, 89.32°E, 16–19.VII.2009, coll. A. Barkalov; 1 Ƥ, Vrangel Island, Ushakovskij settlement, tundra, near pools, 28.VII.1975, coll. A. Barkalov.

Description. Female (described for the first time). Body length: 2.8–2.9 mm, wing length: 3.0– 3.3 mm. Head: Face white, parallel-sided, well developed suture, in middle approximately 2X as broad as width of postpedicel (Fig. 2 F). Proboscis dark-brown; palpus black, with black hairs and silver pollinosity. Frons green with white dusting, shining on upper part. Occiput shining. Antenna black, postpedicel short, triangular, slightly longer than width at base (Fig. 2 G); stylus apical with short hairs, approximately 3X longer than length of postpedicel; ratio of postpedicel length to width and stylus length: 6/5/17. Lower postocular setae white. Thorax: Metallic dark green, scutum with brown pollinosity. Pleura grey pollinose; proepisternum with 1 white seta. Mesonotum without additional setae between dorsocentral and sutural setae; with 5 pairs of strong dorsocentral setae. Acrostichal setae short, arranged in two rows. Scutellum marging with 2 strong setae and 2 short hairs. Legs: Almost entirely black, trochanters and knees yellow. Coxae with white hairs; mid coxa without spur, with group of light hairs on tip. Hind coxa with 1 strong white seta and with some fine hairs. Fore and mid femora without long hairs; fore femur with 1 short preapical seta anteriorly and posteriorly; hind femur with short preapical seta. Fore tibia with 2 short anterodorsal, 2 posterodorsal and 2 posteroventral setae; mid tibia with 2 anterodorsal and 1 posteroventral setae; hind tibia not thickened, with 2 short anterodorsal setae. Fore metatarsus slender (not thickened apically); tarsomeres 5 of fore and mid tarsi flattened and slightly thickened. Tibiae and tarsomere length ratio: fore tibia and tarsus (from 1st to 5th): 33/16/ 8 /4/5/4, mid tibia and tarsus: 45/ 23/10/9 /5/6, hind tibia and tarsus 48/ 16/13/9 /7/6. Wing: Finely infuscate; R4+5 and M1+2 convergent at apex; M1+ 2 in apical part hardly curved. Ratio of part of costa between R2+3 and R4+5 to that between R4+5 and M1+2: 20/7. Apical part of CuA1 longer than dm-cu: 27/10. Lower calypter yellow, with white hairs. Halter yellow. Abdomen: Dark-green, covered with black setae dorsally and white hairs ventrally.

Remarks. Rhaphium beringiense was described only after males collected from the Russian Far East and Alaska (Negrobov 1979). Males and females of this species were collected on the Taimyr Peninsula and in the Altai Mountains. Here we give the description of the female.

In the key to Palaearctic species of Rhaphium (Negrobov 1979), the female of R. beringiense comes closest to R. albomaculatum (Becker, 1891), but differs by black legs and smaller size.

Distribution. PALAEARCTIC: Russia (Chukotka Autonomous Okrug, Vrangel Island), Kamchatka Territory, Krasnoyarsk Territory (Taimyr Peninsula), Magadan Province, Republic of Altai. NEARCTIC: USA (Alaska).