DNA barcoding of fishes from River Diphlu within Kaziranga National Park in northeast India.

DNA barcoding technique has been gaining importance in biodiversity research for its easy and rapid ability of delineating organisms' partial DNA sequences into molecular operational taxonomic units (MOTUs), and identification based on referral sequences from expert identified species. We generated mtCOI barcode sequences from morphologically identified fishes from River Diphlu in northeast India. A portion of this river falls within an important rhinoceros and tiger conservation site, the Kaziranga National Park. Partial mtCOI sequences for 103 fish specimens belonging to six orders, 19 families, 37 genera and 47 a priori identified species, were delineated into 48 MOTUs based on reciprocal monophyly criteria in maximum likelihood and Bayesian tree, and 49 groups by automatic barcode gap discovery (ABGD). Morphological and molecular basis of species identification was congruent for around 80% straightforward cases. We contributed barcodes for eight species which either had no barcodes in databases or are having ambiguous barcodes. We detected four 'near threatened' and two data deficient species as per the IUCN Red List status, besides a few 'least concerned' species. We also observed a wide scope of barcoding studies on fishes from northeast India to cover the endemic species and to resolve the prevailing taxonomic problems.