Nygmia motuoensis Pan & Ouyang, sp. nov.

Fig. 4, 6, 11

Type material. Holotype (Figs 4, 6): male, “ STS-55397, 80K, Motuo County, Linzhi City, Xizang, China, N: 29 °39ˊ4.5″, E: 94°42ˊ51.5″, 25-VII-2015, h [Altitude] 3932 m (coll. Pan Zhaohui)” gen. prep. No. STS-55397 (XAAHU).

Diagnosis: Within the Nygmia genus, the adult of Nygmia motuoensis sp. n. almost identical N. hanuman from Laos, and the genitalia are very similar. However, the differences are as follows: 1) more brown scales in posterior to the middle chamber of the forewings of N. motuoensis sp. n.; 2) the valvae of the N. motuoensis sp. n. were asymmetrical, with a sclerotized small spine at the left base and two small sclerotized spines at the right basal half, while the valva of the N. hanuman was symmetrical, and with a large sclerotized branch in the middle; 3) the N. motuoensis sp. n. has a wisp of caudate spikes in the center of the vesica base, which the N. hanuman does not have. Compared with other congeners, N. motuoensis sp. n. can be distinguished by the aforementioned characteristics of the sclerotized branching valva structure and the central caudate spike at the base of the vesica.

Description. Adult: Male wingspan 38mm. Antennae double-toothed, the antennae yellow, and the doubletoothed brown. Head brownish-yellow, forehead yellow, thorax pale yellow, and the back of the thorax with brownish-yellow tufts. The dorsal plate of the 1st to 3rd abdominal segments on the dorsal surface of the abdomen yellow, yellow-brown hair tufts on both sides of the 1st to 2nd abdominal segments, the rest brown, and an irregular black-brown patch in the middle of the dorsal plate of the 4th and 6th abdominal segments, the ventral surface of the abdomen grayish-yellow. The undercolor of the forewings yellow, the inner and outer lines brown, the half of the midline at the apex of the near wing yellow, the other half brown, the subterminal line yellow, a large number of dark brown scales from the base of the wing to the outer line, the left and right sides of the half segment near the wing end of the midline yellow, the dark brown scales few, the inner, midline, and outer lines arcuate, a black spot in the middle chamber of the forewing, a black oval dot at the terminal line between the R 5 vein and the M 1 vein, the M 1 vein and the M 2 vein, and the marginal hairs yellow. The background color of the hindwings light yellow, with brown scales distributed to the entire wing surface in the upper part, less distribution from the subterminal line to the margin hairs, dark brown hair tufts obviously distributed on each vein between the M 1 vein and the 3A vein, and a brown irregular shape at 1/3 of the R 1 vein, M 1 vein and M 2 vein at the base of the wing. The tufts of anal hairs yellow and broom-shaped.

Male genitalia: Uncus conical, covered with fine hairs. Tegumen broadband-shaped, slight short. Valva asymmetrical, broad base, strong sclerotization, valva base dorsal margin medial side of a long antennae-like protrusion, antennal protrusions membranous, fat, covered with fine hairs, sacculus base with four branches, all sclerotized, two long, two short, the left long branch at the base and middle of the branch each heavy branch out of a short spiny structure, the right long branch and another long branch in the middle and a quarter of its own heavy branch out of a short spiny structure, all sclerotized. Saccus tongue-shaped and well-developed. Many long spines on the apex of vesica, arranged haphazardly, with a caudate spike in the center of the base of vesica, a sclerotized labial sheet on the lower side of the end of vesica, and a group of spines on the ventral surface.

Female. Unknown.

Distribution. The new species is known only in Linzhi, Xizang, China (fig. 11).

Etymology. The specific epithet motuoensis is derived from the type locality, Motuo.