[2][3][4]. The snakes of this genus are poorly studied likely due to their fossorial nature; however, these are common elements of high-elevation herpetofaunal assemblages [3,5,6]. The genus was erected based on types of T. rugosum Gu ¨nther, 1858, now a synonym of T. fuscum, and was placed in the family Colubridae; however, its phylogenetic affinities remained unresolved until recently. Lately, Guo et al. [3,7] showed that Trachischium is sister to a clade including Amphiesma spp., elucidating its deep nested position within Natricidae.Cantor [8] described T. monticola as a member of the genus Calamaria, as Calamaria monticola, from Naga Hills, now in Nagaland, from northeast India, as a species having 224 ventrals and 44 subcaudals, a bright yellow collar and a whitish dorsal line, the ventral being yellow. This species was subsequently reported from several states in northeastern India and the neighbouring countries [4]. In addition to this, two species Cyclophis rubiventer Jerdon, 1870 from Khasi Hills, Meghalaya and Ablabes albiventer Gu ¨nther, 1875 from Darjeeling, western Bengal, bearing 15 rows of dorsal scales, were described, which however were synonymised with T. monticola [1,9]. This taxon, nonetheless, appears to be a complex of cryptic species and