Bayadera bidentata Needham, 1930

(Fig. 4a–h)

Bayadera bidentata: Needham (1930), p. 218, pl. r6, Fig. 7; Asahina (1956), p. 207, Fig. 4; Sui & Sun (1984), pp. 209–211; Davies & Tobin (1984), pp. 22–23; Wilson & Reels (2003), p. 249, Fig. 13; Hämäläinen (2004), p. 388; Do & Dang (2007), p. 31, distribution map [Specimens from Mt Pia Oac, Cao Bang Prov. and Tam Dao National Park, Vinh Phuc Prov.; first record from Vietnam]; Wilson & Zaifu (2007), pp. 99–101, 120, Fig. 4; Zhang (2010), p. 25 (species list).

Materials examined. [Vietnam] 1♂ 1♀, Xuan Son National Park, Phu Tho Prov., 30.V.2015, T. Kompier leg.

(TKC); 1♂, Tam Dao National Park, Vinh Phuc Prov., 18.V.2014, T. Kompier leg. (TKC). [China] 1♀, Zhizhiqu, Zhuangzu, Guangxi Prov., 2–4.VI.2004, H. Karube leg. (KPM); 1♀, Nanling, Guandong Prov., 22–26.VII.2004, Y. Kishida leg. (KPM); 1♀, Nanling, Guandong Prov., 30.VI.2010, Z. Haomiao leg. (KPM); 5♂ 5♀, Damingshan, Guangxi Prov., 6–7.VI.2014, F. Hayashi leg. (FHC).

Notes. Male Bayadera bidentata is characterized by an entirely blackish thorax and abdomen (Fig. 4a), the lower half of the thorax extensively covered with grey pruinosity in life. Wings are hyaline, very faintly tinged yellow from the base to the level of pterostigma (Fig. 4e). Cerci have large spines and two prominent tubercles on inner sides (Fig. 4b–d). Yellow markings of the female thorax vary from the relatively poorly marked type in Guangdong Province, China (Fig. 4f), to the more extensively marked types in Guangxi Province, China and northern Vietnam (Fig. 4g). The tip of female abdomen has one distinct oval spot laterodorsally on S9 (Fig. 4h).

Distribution. Vietnam (Cao Bang [Do & Dang 2007], Phu Tho and Vinh Phuc Provinces), China (Zhejiang, Fujian, Guangdong, Hubei, Guangxi and Sichuan Provinces) (Wilson & Reels 2003, Hämäläinen 2004).