Arge berezovskii Jakowlew, 1891

4. Arge berezovskii Jakowlew, 1891

( Fig. 5 View FIGURE 5 )

Arge berezovskii Jakowlew, 1891: 19 , ♂; Taeger et al. 2010: 126.

Current status. Arge berezovskii Jakowlew, 1891 .

Type locality. China, Gansu, “Kheikho”.

Holotype: ♂, <golden circle> // Хейхо [Kheikho] [ China, Gansu], 21.07.[18]85, Потанин [G.N. Potanin] // arge! // Hylotoma Berezowskii n. // к[оллекциЯ]. А. Яковлева [Collection of A.I. Jakowlew] // Arge berezovskii ( Jakowlew, 1891) , Det. M.C. Wei, 2014 // DEI-GISHym 89420 // HOLOTYPUS Arge berezovskii Jakowlew, 1891 , teste A. Taeger 2018 // Zoological Institute, St. Petersburg INS_HYM_0001901 [ ZISP].

Description. Male ( Fig. 5 View FIGURE 5 ). Body length 6.6 mm; fore wing length 6.2 mm.

Colour. Body black, shining, without clear metallic lustre. Two basal antennomeres black, third orange-brown. Labrum brown, mouthparts light brown. Mandibles darkened at base and at apex, reddish in middle. Legs black, all tibiae white, on fore and middle legs tibiae apices and tarsi slightly darkened, on hind legs tibiae apices up to preapical spurs and tarsi distinctly black-brown. Wings hyaline, veins and pterostigma brown, without spots. Body slightly pubescent with silvery hairs, abdominal tergites almost glabrous.

Head. Head behind eyes significantly constricted. Distance between eyes 1.1 × vertical diameter of eye, vertical diameter of eye 1.5 × its horizontal diameter. POL: OCL: OOL as 1.4: 1.0: 1.6. Middle fovea narrow, closed above and below. Lateral carinae of fovea are narrow and sharp, converging below at acute angle and forming median carina at top of slightly convex supraclipal area. Clypeus flat, on ventral margin broadly semi-circularly excised for one third of its length. Labrum weakly concave along apical margin. Malar space equal to diameter of frontal ocellus.

Antennae. Length of antenna 1.9 × maximum width of head. Flagellum slightly curved in basal third and pointed at apex dorsally. Hairs on anterior surface of flagellum not longer than its width.

Thorax. Thorax uniformly pubescent, with glabrous shining area on lower part of mesopleuron. Smooth and shining, with sparse punctures. Scutellum flat, rounded at apex.

Legs. Middle and hind tibiae with preapical spur, tibial spurs simple. In hind tarsus basal tarsomere longer than three following together.

Wings. On forewing, cell 3Rs equal by length of anterior and posterior margin, vein 3r-m roundly curved. Cell 2Rs twice as long as cell 1Rs. Veins B and M of fore wing join up at same point on vein R. Wing margin between veins M and Cu not ciliate and without glabrous band along margin.

Abdomen. Abdomen slender, slightly oval, simple, length 1.7 × maximum width. Apical tergite on distal margin rounded, with small medial notch. Subgenital plate broad, at apex slightly concave. Subgenital plate in ventral view with rounded posterior margin.

Genitalia as in Fig. 5j View FIGURE 5 , gonostipes broad, convex on inner margin, tapering towards apex. Harpe oval, elongated, length 1.5 × width at base, covered evenly with long scattered hairs. Valve of penis with simple valviceps, flat, bluntly rounded at apex. Valviceps in dorsal view tapered towards apex, with small lateral lobe at base; in lateral view apex forming large rounded lobe, at base of ventral margin narrow but bluntly rounded perpendicular to valviceps lobe. Dorsal process (ergot) clearly visible, almost straight.

Remark. The original description is given for a single specimen, which represents the holotype.