Tactusa brevis Fibiger, new species

(Figs. 12, 13, 21, 25)

Type material. Holotype. Male, China, Guizhou prov., Huangguoshu, 24–26.ix.2008, leg. Han, H.L. & Liu, E., coll. NEFU. Paratypes. 8 males and 7 females. 8 males with data same as holotype, genit. preps 6210, 6223, 6224, 6228, 6229 M. Fibiger, colls NEFU and M. Fibiger; 3 females, China, Yunnan prov., Mojiang, 18–19.ix.2008, leg. Han, H.L., Liu, E. & Wang, Y., genit. preps 6207, 6208 M. Fibiger, colls NEFU and M. Fibiger; 2 females, China, Guizhou prov., Guanling, 22–24.ix.2008, leg. Han, H.L. & Wang, Y., genit. prep. 6211 M. Fibiger, coll. NEFU and M. Fibiger.

Diagnosis. T. brevis belongs in its own species-group (Fibiger 2010). This species-group is interpreted as the most derived in the genus Tactusa . It differs from other species of Tactusa in the uniformly dark brown forewing. In the male genitalia, by the thread-like tegumen, vinculum, and saccus; the short and broad valva; the extremely broad ampulla, somewhat broad comma-shaped, outwardly circular; ventrally with pointed tip; phallus very narrow, S-shaped; carina membranous on dorsal side; ventral side spine-like. In the female genitalia, by the coneshaped, heavily sclerotised antrum, and the very long ductus bursae.

Description. Adult (Figs. 12, 13). Wingspan: 11 – 12 mm, forewing narrow. Head, patagia, and base of costa black; ground colour of forewing brown, with costal-medial dark brown patch, and with dark brown subterminal and terminal area, including fringes; cross-lines black, subterminal line broad, terminal line marked by black interveinial dots; reniform stigma beige-yellow, outlined by black. Hindwing unicolourous grey, with discal spot; fringes grey. Ventral surface unicolourous light brown.

Male genitalia (Fig. 21). Tegumen, vinculum, and saccus thread-like, latter V-shaped; valvae short and broad, asymmetrical, cylindrical, inside open between sacculus and clasper; clasper curved, in right angle between valvae margins; ampullae asymmetrical, left one largest, ventral pointed tips jagged outwardly; digitus absent; juxta semicylindrical, asymmetrical; phallus long S-.shaped; coecum long and broad; carina membranous on dorsal side, ventral side spine-like; vesica unarmed.

Female genitalia. (Fig. 25). Ovipositor rounded, setose; posterior apophyses slightly longer than ovipositor; anterior apophyses untraceable; 7th and 8th abdominal segments totally fused; ostium slightly displaced; antrum cone-like, heavily sclerotised; ductus bursae narrow, 4 times longer than corpus bursae; corpus bursae globular, with cross-shaped signum.

Bionomics. The biotope is a moist, mainly broad-leaf forest, with bushes and herbaceous plants, close to a river. The Mojiang collecting site is a large ravine, with a brook. All specimens were collected at light in midf September. The early stages are unknown.

Distribution. (Fig. 30) China (Yunnan and Guizhou prov.).