Simplicia niphona (Butler, 1878)

(Fig. 18–25, 46–53)

Bocana niphona Butler, 1878, Ill. typical Spec. Lepid. Het. Colln Br. Mus., 2: 56, pl. 38, f. 8. (TL: Yokohama, Japan)

= Simplicia niphona olivacea Prout, 1929, Bull. Hill Mus., 3: 18. (TL: Maskeliya; Patypola [Pattipola], Ceylon [Sri Lanka])

= Simplicia niphona superior Prout, 1929, Bull. Hill Mus., 3: 18. (TL: Mt. Korintji, Sumatra, Indonesia)

Material examined: India, Himachal Pradesh, Kullu Dist., Great Himalayan NP: 1 ♂, Ropa FRH (31.76558ºN, 77.35765ºE, 1515 m), 11.ix.2016, A.K. Sanyal & Party leg. , 1 ♂, 23.ix.2019, K. Mallick & G.N. Das leg . Sikkim, West Sikkim Dist., Khangchendzonga BR: 1 ♂, Gorethang (27.34359ºN, 88.25836ºE, Alt. 1490 m), 01.xii.2019 ; 1 ♂, Yuksom (27.37864ºN, 88.22087ºE, Alt. 1879 m), 19.xi.2019, A.K. Sanyal & Party leg.

Diagnosis: Forewing length: ♂ 18–19 mm. Simplicia niphona can be easily confused with S. xanthoma Prout, 1928 due to close similarity in size and colouration, although the former is slightly larger and darker than the latter. In S. niphona, the forewings have straighter sub-marginal line, less distinct wing fascies, costa distinctly ochreous and lack the marginal series of dark spots compared to those in S. xanthoma (Holloway 2008: 117, pl. 5, f. 269). Butler (1878) while describing S. niphona, discussed its diagnosis with S. turpatalis which is a much smaller species (wingspan: 12–13 lines ≈ 1.2 inch / 30.5 mm as per the original description) and has forewing with more distinct and curved fascies than S. niphona . In male genitalia, S. niphona has broad and gently curved valva of more or less uniform width throughout its length, ventral margin of which is steeply angled distally to join the costal margin in a small costal apical spine, broad vinculum, and aedeagus vesica coarsely scobinated on distal surface with a small distal diverticulum and a shallow, tent-like distal swelling on the surface just next to the diverticulum (Figs. 46–47).

Distribution: India: Himachal Pradesh, Jharkhand, Sikkim, West Bengal (Singh et al. 2018; Chettri & Yonle 2021, present study). Global: Indonesia (Sumatra), Japan, Korea, Malaysia (Borneo, Peninsular Malaysia), Taiwan (Lödl 1999; Kononenko & Han 2007; Holloway 2008).

Remark: This species is recorded from mid to upper montane semi-evergreen forest between 1400–2000 m elevation ranges. Here, we observed variations in the shape of uncus and valva, and size of the costal apical spine in the male genitalia of S. niphona (Figs. 48–53). These include shorter and slightly domed uncus, narrower valva with undulating costal and ventral margins, and slightly larger costal apical spine. Although such differences are not yet reported in any literature, we assume these as individual variations until further studies involving more materials and DNA barcoding.