Promalactis latispinata Wang, sp. nov.

(Figs 4, 22)

Type material. CHINA, Guizhou: Holotype ♂, Fangxiang Town (26.44°N, 108.27°E), Mt. Leigong, 910 m, 4.VIII.2018, leg. ML Zheng et al., slide No. LC19215.

Diagnosis. This species can be distinguished from its congeners in male genitalia by the costa having a digitate process at distal 2/5, the juxta with a large spine at basal 2/3 on the outer margin of the arched lateral arm, and the aedeagus with a cornutus bearing several small spines in the middle.

Description. Adult (Fig. 4). Wingspan 10.0 mm. Head dark grey. Labial palpus with second segment grey on inner surface, yellowish brown mottled with black scales on outer surface; third segment black except white basally and apically. Antenna with scape white dorsally, grey ventrally; flagellum black, alternated with white on dorsal surface. Thorax and tegula dark grey on basal half, yellowish brown on distal half. Forewing ochreous yellow; markings white edged with black scales: costal spot beyond middle, narrowed obliquely outward to posterior angle of cell, with a large diffused black patch on both inner and outer margins anteriorly; cell with a spot before basal 1/3; fold with a fine stripe at base, with a larger round spot at middle and before distal 1/4 respectively; dorsum with three white streaks evenly spaced, outermost one oblique outward to fold; apical spot ovate, with diffused black scales on inner margin; terminal spot smaller, near apical spot; tornus with diffused black scales, forming an ill-defined patch; cilia yellow. Hindwing and cilia grey. Fore- and midlegs black, fore femur and midleg greyish brown ventrally, tibiae with a white spot basally and medially, with a tuft of white scales apically, tarsi white at apices of basal two tarsomeres, apical tarsomere of midleg white; hindleg brown ventrally, grey dorsally, tarsus white at apices of basal four tarsomeres and on entire apical tarsomere.

Male genitalia (Fig. 22). Uncus wide at base, narrowed to basal 2/5, then narrowed to rounded apex. Gnathos slightly shorter than uncus; mesial plate elongate rectangular, sclerotized laterally, obtuse at apex, with an apical process; basal arm shorter than mesial plate. Tegumen widened to posterior 3/5, then divided; lateral arm narrowed to obtuse apex. Valva wide at base, narrowed to rounded apex; costa arched basally, with a straight digitate process slightly oblique outward at distal 2/5, with fine teeth from beyond this process; sacculus wide at base, narrowed to beyond basal 2/3, then widened and setose to apex. Saccus as long as uncus, narrowed to rounded apex. Juxta narrowly connected basally; lateral arm stout, narrow at base, widened obliquely outward to basal 2/3, then arched and narrowed inward to apex, not exceeding costa of valva, with a large spine at basal 2/3 on outer margin. Aedeagus stout, shorter than valva; apex straight, with a hooked process; cornutus a long spine, 2/3 length of aedeagus, bearing several small spines in middle.

Female unknown.

Distribution. China (Guizhou).

Etymology. The specific epithet of the new species is derived from the Latin lati- and spinatus, referring to the spine on the outer margin of the juxta lateral arm.