Boiga nuchalis (Günther, 1875)

(Fig. 1–2; Table 1)

Suggested common name: Collared cat snake.

Additional specimens examined. (n=12). INDIA. CESS270 collected by AKM from Thadiyendamol (12.229N 75.623E; 1336 m asl), Kodagu dt., Karnataka; CESS310 collected by CM from Iruppu falls (11.969N 75.985E; 856 m asl), Kodagu dt., Karnataka; CESS315 collected by CM from Potachipara (12.077N 75.805E; 190 m asl), Bramagiri, Kodagu dt., Karnataka; CESS192 collected by IA & AD in 2011 from Kolli Hills (11.295N 78.377E; 1100 m asl), Namakkal dt., Tamil Nadu (Eastern Ghats); CESS081 collected by AKM in 2010 from Meppadi (11.589N 76.099E; 757 m asl), Kalpetta, Waynad dt., Kerala; CESS085 collected by SP & MP in 2010 from Kalpetta (11.588N 76.100E; 775 m asl), Waynad dt., Kerala; CESS094 collected by SP & MP in 2010 from Siruvani (10.987N 76.622E; 789 m asl), Palghat dt., Kerala; CESS165 collected by SP & MP in 2010 from Vazhachal (10.303N 76.593E; 233 m asl), Idukki dt., Kerala; CSPT /S-85 Madurai dt., Tamil Nadu; SACON /VR-73a–b two from Meghamalai; SACON /VR-73c one from Anamalai; SACON /VR-73d one from Ooty.

Complementary Diagnosis. Boiga nuchalis is phylogenetically sister (node support 100%) to a clade consisting of B. ceylonensis and B. whitakeri sp. nov. that in-turn cluster with high support (97%). Boiga nuchalis is 5.9–6.5 % divergent from B. ceylonensis and 5.1–5.9% from B. whitakeri sp. nov. at cyt b.

Comments. Our new genetic results (see Fig. 1) support the earlier notion of Ganesh et al. (2020) that the populations in the Western Ghats and the disjunct ones occurring in the Southern Eastern Ghats are all conspecific and represent a single widespread species. The highest intraspecific divergence documented in this species is 2.6%, between samples from Coorg and Wayanad, and 1.4% divergence between Kolli Hills and Coorg at cyt b.