Flexocerus sinuatus Xue & Zhang sp. nov.

(Figs. 1 A–H, 2)

Description. Length (including wings): male 6.0 mm, female 6.2–6.7 mm.

Crown stramineous; face mainly yellowish; frontoclypeus brownish basally, with dark brown tinge on median line, lateral margin brown; anteclypeus dark brown, yellowish brown anteriorly; lateral frontal sutures terminating at pair of black spots ventromesad of ocelli; ocelli transparent; gena and lora ochraceous, with gray stripes. Pronotum yellowish anteriorly and brown basally, with brown stripes (Figs. 1 C–D). Forewing brownish, veins dark brown. Scutellum yellowish, basal triangles and disc black. Mesoepimeron and legs ochraceous, hind leg macrosetae brownish (Fig. 1 B).

Face with lateral frontal sutures straight; other characters as in generic description.

Male pygofer rectangular, caudal margin rounded, dorsal margin with apodeme; pygofer with dense short setae and concave on ventral margin subapically, inner surface with a finger-shaped process (Fig. 3 A). Valve with caudal margin convex in middle (Fig. 3 B). Subgenital plate narrow and elongate, with dense long fine setae on dorsal and ventral margin, fine setae on lateral surface. Style broad subapically, tapering apically, apex pointed, with more than 20 teeth on apical half ventral margin, few short setae on lateral surface in middle (Fig. 3 G). Aedeagus Sshaped, with 3 processes, pair of long ventral subapical processes medially above gonopore and shorter process medially below gonopore; dorsal apodeme with pair of winglike apical extensions in ventral view; gonopore subapical (Figs. 3 E–F).

Female 7th sternum shorter than wide, rectangular, apical margin with a triangular concavity in middle. Second valvulae curved dorsally, with sixteen dorsal teeth; first valvulae sculpture strigate, apex compressed and pointed (Fig. 2).

Etymology. The specific epithet refers to the aedeagal shaft sinuate.

Material examined. Holotype: ♂, CHINA, Guangxi Prov., Guilin, Liangfeng, 27.iv.1952 (IOZ). Paratype: 1♂ 2♀♀, same data as holotype (IOZ); 1♀, CHINA, Guangxi Prov., Guilin, Liangfeng, 30.iv.1952 (IOZ); 1♀, CHINA, Guangxi Prov., Guilin, 8.vi.1984 (IOZ).

Remarks. This species is similar to F. citrinus Li and F. flexureus Kuoh & Fang in face color, but differs from the latter in having the pygofer with a finger-shaped process on the inner surface ventrally, and the aedeagus with 3 processes on the ventral surface.