DNA barcoding adjudicate two different morphs of Bascanichthys deraniyagalai (Anguilliformes: Ophichthidae): re-description and first record from Chilika lagoon, India

Abstract

Morphological characters and distribution pattern of the snake eel, Bascanichthys deraniyagalai is debatable during the past half-century. Thus, the species is re-described herewith by morphometry, vertebrae, and molecular data. In recent Chilika expedition in India, we have collected 10 specimens and observed a vertebral count dimorphism. The present study distinctly detected two vertebral groups of B. deraniyagalai: first group with 5 predorsal vertebrae, 81–83 preanal vertebrae, 190–196 total vertebrae in females; however, the sex of the second group with 5 predorsal vertebrae, 72–74 preanal vertebrae, 176–178 total vertebrae was not able to confirm. Further, the molecular data of morphologically identified two distinct groups of B. deraniyagalai shows negligible Kimura 2 parameter genetic divergence and cohesive clustering in Neighbor-Joining phylogeny proved to be the two different morphs of the same species. Hence, the present study indicated there might be vertebral count or sexual dimorphism in B. deraniyagalai, which need further sampling and taxonomic revision to unwrap the fact.