Xestomyia atrox Sorokina & Pont, 2011

Vikhrev, Nikita E. & Sorokina, Vera S., 2017, Taxonomic notes and faunistic data on the Muscidae (Diptera) of the Altai Mountains (Russia), Zootaxa 4311 (2), pp. 241-254 : 248-249

Xestomyia atrox Sorokina & Pont, 2011

Fig. 1A

Xestomyia atrox Sorokina & Pont, 2011: 40 . Type locality: Russia, Altai Republic.

Material examined. RUSSIA, Altai Republic: 1♂ 1♀, Aktash env., 50.326°N 87.739°E, 2600 m asl, 6.07.2016, leg. N. Vikhrev ( ZMUM).

Remarks. The genus Xestomyia Stein, 1907 includes only five species all of which are confined to high altitudes in the mountains and plateaux of Central and East Asia and are scarce and rarely collected ( Sorokina & Pont 2011). Only one species of this genus is known from Altai Mts., Xestomyia atrox Sorokina & Pont, 2011 , which was described from a single male collected from marmot burrows [Altai Republic, Chikhacheva range, upper Naryn-Gol river, 49.816°N 89.533°E, 2520–2600 m asl, 15– 19.07.2009, V. Sorokina]. During an expedition to the Altai in July 2016, the additional material of this rare species including the previously undescribed female was collected.

Notes on male. The newly collected male fits the description of Xestomyia atrox Sorokina & Pont, 2011 except for only 2 pv setae on t2 (the holotype has 3 pv on t2). The description of Xestomyia atrox ( Sorokina & Pont 2011: 41) stated “ pra 2 times as long as posterior notopleural seta”. It was an error and the holotype has pra 0.5x as long as notopleural setae.

Description of female. Body length 5 mm. Body black with distinct green shine.

Head: Frons wide, at level of anterior ocellus 0.37 of head width. Interfrontalia black; fronto-orbital plate and parafacial grey-brown, with a large shining black spot at level of insertion of antenna. Fronto-orbital plate with 7 strong setae: 3 inclinate in anterior half and 4 exclinate in posterior half; crossed interfrontal setae present and remarkably strong. Mouth-edge distinctly projecting. Arista very short pubescent. Palpus black. Proboscis slender and elongate, labella medium large.

Thorax: Prst ac in 2 rows, 2+3 dc. Notopleuron with 2 long setulae between notopleural setae. Katepisternal setae 1+1. Prealar seta strong, but short and 0.5x as long as notopleural setae. Meron and katepimeron bare. Wing with a slight brownish tinge; costa spinulose. Haltere black; calypters white.

Legs: t1 with 1–2 pv setae below middle. f2 with 4 strong av in basal half and 1 near apex; a complete row of about 10 pv. t2 with 2 pd, 2(3) pv, 1 ad. f3 with a complete row of 10 av, the setae stronger in apical half. t3: 3 av in apical half; a complete row of 7 ad of different length; 1 pd and 6–7 short spinulose pd around it.

Abdomen: Black, green shining, without any dusting.

Figures

FIGURE 1. A. Xestomyia atrox (female). B. Phaonia fusca (female, lectotype of suspiciosa Stein). C, D, F. Hydrotaea hsiai: C. Female. D. Male. F. Male mid tarsomere 1. E. Hydrotaea tuberculata, male mid tarsomere 1. G. Thricops aduncus, male hind tibia.