Cyana bianca (Walker, 1856)

(Figs. 1–4, 25–27, 37, 45)

Bizone bianca Wаlker, 1856, List of the Specimens of Lepidopterous Insects in the Collection of the British Museum 7: 1684 (Type locаlity:“Hindostаn”).

Material examined. NEPAL: 1 ♂, Nepal, Mechi, Taplejung area, Tamur Valley, 4 km N Dobhan, 800 m, 87°40’E, 27°22’N, 22.X.1996, leg. Gy.M. László & G. Ronkay, slide MWM 33492 Volynkin (Coll. MWM/ ZSM) ; INDIA: 1 ♂, Sikkim, 1800 ft., VI.1897, Dudgeon [leg.] (Coll. NHMUK); 1 ♀, Sikkim, Noand / Felder Colln. / Rothschild Bequest B.M. 1939.-I. ( Coll. NHMUK) ; 1 ♂, Darjeeling / Moore Coll. 94-106. ( Coll. NHMUK) ; 2 ♀, Digboi, Assam (L. Brunt) / Rothschild Bequest B.M. 1939.-I. ( Coll. NHMUK) ; 1 ♀, Khasis, X.1896, Nat. Coll. / Rothschild Bequest B.M. 1939.-I. (Coll. NHMUK) ; 1 ♂, 2 ♀, Sikkim, O. Möller / Rothschild Bequest B.M. 1939.- I. ( Coll. NHMUK) ; 1 ♂, 3 ♀, Sikkim, 4000–7000 ft., Möller / Rothschild Bequest B.M. 1939.-I. (Coll. NHMUK); 2 ♀, Tezpore, Assam / Rothschild Bequest B.M. 1939.-I. ( Coll. NHMUK) ; 1 ♀, Darjeeling, ex coll. Lidderdale, Joisey coll., Brit. Mus. 1922-306 (Coll. NHMUK) ; 22 ♂, 6 ♀, NE India, Assam, Pan Bari Reserv Forest, 27°08'N, 94°00'E, 4–7.VII.1997, leg. Sinjaev & Murzin, slides ZSM Arct . 136/2017 ♂, ZSM Arct. 137/2017 ♀ Volynkin ( Coll. MWM/ ZSM) ; 2 ♂, NE India, Assam, Nambor Reserv Forest, Garampani, h= 100 m, 26°30'N, 93°56'E, 21– 29.XI.1997, leg. V. Siniaev & M. Murzin, slide MWM 34571 Volynkin (Coll. MWM/ ZSM) ; 2 ♂, 2 ♀, NE India, Assam, Nameri Nat. Park, 40 km N Tezpur, 150 m, 27°20'N, 93°15'E, 24.VII–2.VIII.1997, leg. Sinjaev & Murzin, slide MWM 34570 Volynkin (Coll. MWM/ ZSM) ; BANGLADESH: 1 ♀, Konapara, Kalam / Rothschild Bequest B.M. 1939.-I. ( Coll. NHMUK) .

Diagnosis. Forewing length is 14–16 mm in males and 17–19 in females. Cyana bianca (Figs. 1–4) has no significant external differences from C. indosinica sp. nov. (Figs. 5–10) and C. malayana (Figs. 11–16). The male genitalia of C. bianca (Figs. 25–27) are similar to those of C. indosinica sp. nov. (Figs. 28–30) by the weak ampulla, but differ in the triangular lateral lobes of the vinculum (while in C. indosinica sp. nov. and other species the lobes are more rounded), the much shorter and narrower medial posterior, medial anterior and distal diverticula, and the narrower medial dorsal diverticulum. The female genitalia (Fig. 37) differ from those of other related species (Figs. 38–41, 43, 44) more clearly than the male genitalia, and are characterized in the shorter ductus bursae, the long, narrow and weakly rugose posterior sclerotized plate of the corpus bursae, the heavily sclerotized medial-lateral sclerotized band (which is broader, shorter and much more weakly sclerotized in C. indosinica sp. nov. and C. malayana and is absent in C. quadripartita), and the significantly larger anterior signum.

Distribution (Fig. 45). Nepal (Kishida 1994), N and NE India (Arunachal Pradesh, Himachal Pradesh, Sikkim, Assam, Meghalaya) (Kirti et al. 2013), Bangladesh. All records of C. bianca for Indochina (Candèze, 1927; de Joannis, 1928; Černý & Pinratana 2009; Bayarsaikhan & Bae 2016) belong to C. indosinica sp. nov. and C. malayana .