Abstract:
The saw-scaled viper (Echis carinatus) is a member
of the Viperidae family, known for its intricate taxonomic
history. Initially, it was believed to be a unique Sri Lankan
subspecies called E. c. sinhaleyus. The subsequent clinical
evidence also suggests the presence of a distinct subspecies
in Sri Lanka. However, its existence was later questioned,
urging the need for genetic studies. Therefore, it was aimed to
unravel the molecular phylogenetic affinities of the Sri Lankan
population of E. carinatus. For the first time, the molecular
phylogenetic affinities and phylogeography of the Sri Lankan
population of E. carinatus were explored. This study was based
on sequences of samples obtained from 12 locations across the
Northern Province, using mitochondrial markers Cytb, NADH4,
16S, and 12S. Molecular phylogenetic analyses showed that the
South Indian and Sri Lankan populations of E. carinatus form a
reciprocally monophyletic clade, which is recovered as the sister
group to the remaining groups of E. carinatus. Based on the
divergence-time estimates, the divergence between Sri Lankan
and South Indian population of E. carinatus is estimated to have
occurred in the mid Pleistocene epoch. This study discloses
that E. carinatus comprises two distinct subspecies namely,
E. c. carinatus and E. c. sochureki. The Sri Lankan and South
Indian populations belong to the subspecies E. c. carinatus,
whereas E. c. sochureki comprises the remaining populations
of E. carinatus distributed across northern, western, and eastern
India (Rajasthan, Maharashtra, Odisha, and Goa), as well as in
Pakistan, Sharjah, and Iraq.
