Genetic differentiation and phylogenetic relationship of 11 Asian Sisorinae genera (Siluriformes: Sisoridae) with new record of Pseudolaguvia foveolata.

Abstract

Studies on Sisorinae systematics have been largely restricted to morphological data with few studies on examination of phylogenetic relations. However, no study has been done to evaluate genetic distance of the genera under Sisorinae sub-family and detailed phylogenetic relations within it. We used nuclear recombination activating 2 (rag2) gene and mitochondrial cytochrome c oxidase I (COI) gene from 64 species to examine genetic differentiation and phylogenetic relationships within 11 Asian Sisorinae genera. The range of interspecies K2P distance for rag2 was 0-0.061 and COI was 0-0.204. Phylogenetic analysis based on maximum likelihood (ML) and Bayesian (BI) approaches for each locus individually and for the concatenated rag2 and COI sequences revealed three major subclades viz. Bagariini, Sisorini and Erethistini under subfamily Sisorinae. The analysis based on COI gene showed ((Sisorini, Bagariini), Erethistini) relationship. Rag2 and combined rag2 and COI showed ((Sisorini, Erethistini), Bagariini) relationship. Combined rag2 and COI analyses resulted into better resolved trees with a good bootstrap support. In this study, new record of Pseudolaguvia foveolata (Erethistini) has been documented based on 13 specimens collected from Torsa River, Jaldapara, Alipurduar district, West Bengal, India (26°43'44.66″ N and 89°19'32.34″ E), extending its distribution range in Brahmaputra drainage, India. The genetic distance between the P. foveolata new record and the reported P. foveolata (holotype: UMMZ 244867) was 0.00 at both rag2 and COI locus and it was further grouped with P. foveolata Type specimen (holotype: UMMZ 244867) with 100% bootstrap support. This report gives additional information on occurrence of the species P. foveolata, along with discussion on morphometric, meristic and molecular (COI and rag2 gene) data.