DNA barcoding elucidates the population genetic diversity of venomous cobra species (Reptilia: Elapidae) in Indo-Bangladesh region

摘要

The DNA barcode data of venomous cobra species (Naja naja and Naja kaouthia ) are limited in the global database, especially from India and Bangladesh. Owing to the rapid success of DNA barcoding for discriminating a variety of species around the world, the present study aimed to generate the mitochondrial cytochrome c oxidase subunit I (COI) gene information of two morphologically identified deadly elapid species from the Mizoram state in northeast India and Rangpur in northern Bangladesh. The multiple species delimitation methods: Automatic Barcode Gap Discovery (ABGD), General Mixed Yule-Coalescent (GMYC), and Poisson-Tree-Processes (bPTP) revealed 14, 16, and 18 molecular operational taxonomic units (MOTUs) for 12 Naja species. The binocellate cobra, N. naja showed monophyletic clustering in both maximum-likelihood (ML) and Bayesian (BA) trees, single MOTU in ABGD and GMYC, and negligible intra-species genetic distance (0.2%) with two haplotypes. However, the monocellate cobra, N. kaouthia showed paraphyletic and polytomy in ML and BA phylogenies respectively; more than one MOTUs in ABGD, GMYC, and bPTP analyses; and sufficient intra-species genetic distances (0.6–2.3%) with five haplotypes related to the diverse geographical locations in Bangladesh, China, India, and Thailand. By superimposing the executed species delimitation criteria, the present molecular-based investigation concludes the presence of cryptic diversity of N. kaouthia in Indo-Bangladesh, China, and Thailand.