A new species of Lycodon Boie, 1826 (Serpentes, Colubridae) from northern Vietnam

Abstract

A new species of the genus <i>Lycodon</i> is described from Cao Bang Province, Vietnam, based on three individuals with distinct differences in morphology and molecular data. The new species is differentiated from its congeners by a combination of the following characters: dorsal scales in 17-17-15 rows, smooth throughout; supralabials usually eight (rarely nine); infralabials ten; one elongated loreal on each side, in contact with the eye; precloacal plate single; ventral scales 212-218 (plus one or two preventral scales); subcaudals 90 or 91; maxillary teeth 13 or 14; dorsal surface of body with 28 or 29 light body bands; dorsal surface of tail with 13 cream bands, forming a distinct blotch in the vertebral region. Based on phylogenetic analyses of mitochondrial cytochrome <i>b</i> sequence data, the new species is recovered as the sister species to a clade containing <i>L. multizonatus</i> and <i>L. liuchengchaoi</i> with strong support from the Bayesian analysis. The new species is at least 7.5% divergent from other species within this clade in uncorrected pairwise distance calculated using a fragment of more than 1000 bp of the mitochondrial cytochrome <i>b.</i> This discovery increases the number of <i>Lycodon</i> species known from Vietnam to 16.