Apteronotus indigus Kang, Hu & Luo sp. nov.

Figs 1A-H, 2A-F

Type material.

Holotype, ♀, card mounted, China, Xinjiang, Ruoqiang County, Altun Mountain Nature Reserve, 36°58′10″N, 90°14′45″E, Altitude: 4021.95 m, 14.VII.2020, Coll. Shun-Gang Luo, Ning Kang, Hong-Ying Hu by yellow pan trapping. Paratypes. 1♀, 1♂, on slide, same data as holotype except 18.VII.2020; 3♀♀, 5♂♂, card mounted, 21.VII.2020. Coll. Shun-Gang Luo, Ning Kang, Hong-Ying Hu (all deposited in ICXU).

Description.

Female. Length 0.7 mm. Body black with dark bluish metallic sheen (Fig. 1A). Antenna, femora, and tibiae dark brown, head in dorsal view with bronze shine at some angle. Mesosoma black. Legs with all coxae black; trochanter and their apices deep yellow, tarsal segments 1-3 yellow, fourth and fifth tarsi dark brown (Fig. 2C). Gaster black except T6-7 dark brown.

Head in frontal view 1.2 × as broad as high (385:330) (Fig. 1B), 1.9 × as broad as mesosoma, with fine reticulate sculpture, covered with sparse and short setae; frontovertex width 0.5 × head width (117:385), antenna located below the lower eye margin and separated from clypeus margin by 1.4 × height of the torulus, inner edge of eyes diverged at the lower part, malar sulcus distinct and straight, malar space 0.65 × as long as eye height (120:185), mandible bidentate. Head in dorsal view 2.1 × as broad as long (347:168), ocelli forming an obtuse angle (110°), POL 1.8 × as long as OOL (55:30), posterior edge of eye adjacent to posterior margin of head. Antenna with scape cylindrical and covered with short setae, 9 × as long as wide (260:28), pedicel 2 × as long as wide (60:30); all funicular segments longer than wide (Fig. 1C), each funicular with three rows of irregular longitudinal sensilla, F1 and F3 2 × as long as broad respectively (40:20), obviously shorter than pedicel and other segments, F4-F6 subequal in length, 1.5 × as long as broad (45:30); clava 3-segmented, 3.6 × as long as broad (145:40), longer than the combined length of F5-F6, with obscure boundaries and apically rounded, the collective length of pedicel and flagellum 1.22 × as long as head width (470:385).

Mesosoma much shorter than metasoma and reticulate sculpture larger than that on head. Pronotum 1.8 × as long as mesoscutum length (90:50) and 2.78 × as broad as long (250:90); mesoscutum 5.2 × as wide as long (260:50) (Fig. 1D), notaular lines absent, tegula large and semicircular; scutellum slightly convex and 2.2 × as wide as long (250:117), scattered with some short white setae irregularly arranged on its posterior part, axillae very small and apically separated; propodeum medially longer than 1/3 of the scutellum (40:117), with sinuated inverted U-shaped ridges (Fig. 1F). Mesotibial spur strong, 0.6 × as long as basitarsus (63:104) (Fig. 1E). Wings absent.

Gaster 1.6 × as long as broad (694:426), longer than the combined length of head and mesosoma, T1 distinctly longer than other tergites individually (250:444), occupying about two-fifths of the total length, covered with 3-4 rows of setae, T2-T6 each with a single row of setae, T7 with 2-3 rows of short setae, and with 5 long cercal bristles at each side. Paratergites absent. Hypopygium slightly extends to the apex of gaster (Fig. 1G, H).

Male. Length 0.57-0.64 mm (0.6 ± 0.042 mm, N = 5) (Fig. 2A-C), similar to female in body color and sculpture, but differs as follows. Frontovertex slightly arched (Fig. 2D); each funicular segment clearly elongated, 3 × as long as broad, with at least 2 rows of long black whorled setae (Fig. 2E); pedicel distinctly shorter than F1, 0.67 × as its length; clava 4.25 × as long as broad; the combined length of pedicel and flagellum 1.6 × as long as head width. Gaster 1.3 × as long as broad, posterior margin of each tergite straight (Fig. 2F).

Hosts.

Unknown.

Etymology.

" indigus " means indigo blue, signifying the body color of the female species.