Tylostega serrata Du & Li, sp. nov.

(Figs. 5, 12, 17)

Type specimens. Holotype ɗ, CHINA: [label 1] “Song County (34°08' N, 112°05' E), Henan Province / 1580 m elev. / 22. VII. 2002 / leg. Xinpu Wang”; [label 2] “genitalia slide ɗ / DXC05140”; [label 3, red] “ Holotype ɗ / Tylostega / serrata / Du & Li”. Paratypes: 1 ɗ, Wen County (32°58' N, 104°41' E), Gansu Province, 1950 m, 4. VII. 2001, leg. Houhun Li & Xinpu Wang; 2 ɗ, Lushi County (34°03' N, 111°02' E), Henan Province, 1200 m, 20. VII. 2001, leg. Dandan Zhang; 9 ɗ, Song County (34°08' N, 112°05' E), Henan Province, 1560 m, 22, 24. VII. 2001, leg. Dandan Zhang, 1580 m, 18–22. VII. 2002, leg. Xinpu Wang; 1 ɗ, Shangsi (22°09' N, 107°58' E), Guangxi Zhuangzu Autonomous Region, 510 m, 6. IV. 2002, leg. Shulian Hao & Huaijun Xue; 1 ɗ, Jinxiu Yaozu Autonomous County (24°08' N, 110°11' E), Guangxi Zhuangzu Autonomous Region, 550 m, 15. IV. 2002, leg. Shulian Hao & Huaijun Xue.

Diagnosis. This species is similar to T. tylostegalis (Hampson) externally, but can be distinguished by the valva with a large elliptical projection medially; the smooth dorsal margin of the sacculus inflated triangularly at middle; the phallus with one short and stout spine­like and one dentate cornuti. In T. tylostegalis the valva has a small triangular projection medially; the dorsal margin of the sacculus bears small teeth; and the phallus has three spine­like cornuti.

Description. Male (Fig. 5). Wing span 19.0–22.0 mm. Frons yellowish­white except fuscous anteriorly. Antenna with ventral cilia about as long as flagellomere diameter in male, minute in female. Labial palpus white or yellowish­white, 2nd segment fuscous or brown dorsally and distally, 3rd segment pale yellow. Thorax yellowish­white dorsally, each segment with a fuscous blotch. Patagium and tegula yellowish­white or pale yellow, mottled brown. Forewing pale yellow diffused with brown, with fuscous or black patches at base; discoidal stigma blackish­fuscous; lines blackish­fuscous, broader and darker on costa; antemedial line slightly excurved; postmedial line sinuated as in T. pectinata; a series of blackish­fuscous spots along terminal margin. Hindwing yellowish­white, with large fuscous patch at base; discoidal stigma dark fuscous, claviform; a broad region consisting of brown patches extending from middle of inner margin obliquely to costal and terminal margins; some fuscous spots placed along terminal margin. Cilia of both fore­ and hindwings light brownish­yellow, paler distally. Abdominal segment 1 white with two fuscous patches, the remaining segments pale yellow and suffused with fuscous on 2nd–5th segments dorsally; ventral surface white or yellowish­white.

Male genitalia (Figs. 12, 17). Uncus height greater than basal width. Valva gradually narrowed from base to apex, with large, median elliptical projection bearing dense small spines anteriorly, and with sclerotized flat process near apex of sacculus. Sacculus concave at basal 1/3 on dorsal margin, inflated triangularly at middle, then gradually narrowed to subapex, distally inflated triangularly. Saccus short and broad, triangular, bluntly rounded on anterior margin. Juxta circular, concave on posterior margin, protruding posterolaterally. Phallus with one short and stout spine­like and one dentate cornuti.