Rhaphium borisovi Negrobov, Barkalov & Selivanova, sp. nov.

Rhaphium borisovi Negrobov, Barkalov & Selivanova sp. nov.

(Figs. 2 A–D)

Type material. HOLOTYPE, 3 labeled: Russia: Taimyr 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 (SZM). PARATYPES: Russia: 6 3, same data as holotype.

Diagnosis. This species is similar to R. gruniniani Negrobov, 1979, but differs by yellow apical half of fore coxa and tips of mid and hind coxae; subequal lengths of hind tarsomeres 1 and 2, and broad inner lobe of cercus. Rhaphium gruniniani has entirely black coxae, hind basitarsus slightly shorter than hind tarsomere 2 and inner lobe of cercus narrow.

Description. Male. Body length: 2.4–2.8 mm, wing length: 2.5–2.6 mm. Head: Face silvery-white, with parallel sides, in middle slightly wider than width of postpedicel (5/4). Proboscis dark-brown; palpus black, with black hairs and whitish pollinosity. Frons green, grey pollinose. Antenna (Fig. 2 A) black, postpedicel elongated triangle, 8X longer than wide near base; stylus unmodified, not broadened apically, with short hairs, shorter than postpedicel is wide at base, apical. Ratio of postpedicel length to width and stylus length: 40/5/4. Lower postocular setae white. Thorax: Metallic green, scutum with bronze tinge; pleura grey pollinose; proepisternum with group of short pale-yellow hairs; 4 pairs of strong dorsocentral setae preceded by 1 short seta. Acrostichal setae distinctly developed arranged in two rows. Scutellum with 2 strong black lateral setae 2 short hairs. Legs: Largely yellow, with dark base of fore coxa, mid and hind coxae (except tips), fore femur on dorsal and anterior sides, fore and hind tarsi, mid and hind tibiae and tip of hind femur. Coxae with white hairs, group of light setae on top of mid coxa, not forming spur; hind coxa with 1 strong white seta and fine hairs. Femora without long hairs; mid and hind femora with 1 short preapical seta. Fore tibia with 2 short anterodorsal, 1 posterodorsal and 1 posteroventral setae, in apical third with row of short posteroventral setae. Mid tibia with 2 anterodorsal, 2 posterodorsal and 1 posteroventral setae. Hind tibia not swollen, with 2 short anterodorsal, 2 posterodorsal and 1 anteroventral setae. Fore basitarsus not swollen at tip, with short ventral setae. Mid and hind tarsi not broadened, mid basitarsus with short ventral setae, hind basitarsus without strong seta. Tibiae and tarsomere lengths ratio: fore tibia and tarsus (from 1st to 5th): 29/11/7 /5/3/4, mid tibia and tarsus: 38/18/9 /6/4/4, hind tibia and tarsus 50/ 12/13/9 /6/5. Wing: Weakly finely infuscate; R4+5 and M1+2 convergent, at apex parallel. 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: 16/7. Distal part of CuA1 longer than dm-cu (20/10). Lower calypter yellow with white cilia. Halter yellow. Abdomen: Green with bronze tinge, tergites with black setae and hairs; sternites with white hairs. Epandrium and surstylus dark-brown; surstylus with broadened basal part, with dorsal arm (Fig. 2 D). Cercus bilobed (Fig. 2 B–C), longer than hypandrium, inner lobe of cercus long and broad, oval at tip; external lobe narrow band-like, its length approximately equal to two-thirds length of inner lobe.

Female. Unknown.

Distribution. Russia: Krasnoyarsk Territory (Taimyr Peninsula). This species is known only from the type locality (Fig. 1 A).

Etymology. The species is named after the Russian Odonatologist, Dr. Sergei N. Borisov (Novosibirsk).