Arge subtilis Jakowlew, 1891

28. Arge subtilis Jakowlew, 1891

( Fig. 40 View FIGURE 40 )

Arge subtilis Jakowlew, 1891: 19–20 , ♀); Taeger et al. 2010: 140.

Current status. Arge subtilis Jakowlew, 1891 .

Type locality. China, Gansu, “Tan-Chan”.

Holotype: ♀, <golden circle> // Танъ-Чанъ [Tan-Chan] [ China, Gansu], потанинъ [leg. G.N. Potanin], 18.06.[18]85. // Hylotoma subtilis Yak [owlew]. // к[оллекциЯ]. А. Яковлева [Collection of A.I. Jakowlew] // Arge subtilis ( Jakowlew, 1891) , Det. M.C. Wei, 2014 // DEI-GISHym 89449 // HOLOTYPUS Arge subtilis Jakowlew, 1891 , ♀, teste A. Taeger 2018 // Zoological Institute, St. Petersburg INS_HYM_0001937 [ ZISP].

Description. Female ( Fig. 40 View FIGURE 40 ). Body length 7.3 mm; fore wing length 7.1 mm.

Colour. Body black, with slight bronze-green metallic lustre; tibiae, tarsi, apices of fore femora yellowish-white, apices of middle tibiae and middle and hind tarsi slightly darkened, hind tibiae in apical third black. Mouthparts and flagellum brown. Wings hyaline, veins and pterostigma light brown. Pubescence yellowish-white.

Head. Head behind eyes slightly expanded. Distance between eyes 1.4 × vertical diameter of eye; eye with vertical diameter 1.8 × its horizontal diameter. Postocellar area not convex, without anterior and lateral furrows. POL: OCL: OOL as 1.1: 1.0: 1.3. Medial fovea broad, flat in lower part, with weak rounded pit in upper part, open towards frontal area. Lateral carinae sharp, converging downwards, joining in indistinct median carina. Supraclypeal area weakly convex, densely punctuated and wrinkled. Malar space equal to diameter of frontal ocellus. Clypeus smooth and sparsely punctured, with rounded medial notch on ventral margin. Labrum with weakly notched on ventral margin.

Antennae. Antennal length 1.3 × maximum head width; flagellum weakly curved at base, widened towards apex, apex narrowly rounded; its setae short, dense, closely adherent.

Thorax. Mesopleurae in lower part with glabrous band; scutellum flat, broadly rounded at apex.

Legs. Middle and hind tibia with preapical spurs; tibial spurs simple. Basal tarsomeres of hind tarsus longer than next three combined.

Wings. Veins B and M of fore wing join up at same point on vein R. Membrane of cell 1Rs densely covered with short setae.

Abdomen. Abdomen parallel; tergites in basal half smooth, in apical part densely pubescent. Saw sheath 1.7 × as long as wide, simple, parallel-sided, bluntly rounded at apex (ventral view), on inner surface with small, blunt spines; in lateral view triangular, broadly rounded at apex, convex on ventral margin.

Lance in lateral view slightly convex, medially with pronounced annuli. Maximum width of lance equal to lancet width. Carina of apical part of dorsal margin with finely, irregular and indistinct denticles, remaining part of dorsal margin with longitudinal shallow fossa. Lancet with straight dorsal and convex ventral margin. Annuli curved and dorsally inclined, apically towards base, basally towards apex. Annular spines (ctenidia) short, simple, several times shorter than width of annulus. Ventral margin with 13 well-distinct serrulae in basal part. Serrulae smooth, with only indistinct denticles. Serrulae in apical third indistinguishable, medially triangular, oblique, with bluntly rounded apex, in basal part rounded. Between serrulae one (rarely two) long and straight pore canals of marginal sensilla.

Remark. The original description is given on a single specimen ( holotype). The males are unknown.