DNA barcoding of fishes from River Song, Dehradun, Uttarakhand using mitochondrial cytochrome-c oxidase-I gene

Abstract

The entire Himalayan region is well known as a global hotspot for biodiversity. Many workers have documented different aspect of biodiversity.  The Uttarakhand Himalaya region, a part of Himalayan system, is very rich in fresh water aquatic biodiversity because it has many fresh water streams and rivers within a short distance of 200 miles. All these fresh water bodies harbor diverse aquatic fauna with fishes being the most extensively studied. There are many fish species reported by many authors in Uttarakhand. Many of the fishes have similar morphological characters (morpho-metrics) and are difficult to identify. Attempts have been made to generate the DNA barcode of fishes but most of the attempt are limited to major rivers i.e. the Ganges and the Yamuna. Besides these two prominent river (the Ganges & the Yamuna), there are many supporting streams and small tributaries that are also inhabited by many species. No “long term” and “entire river scan” for fish species has ever been conducted in Uttarakhand. Our research aims to generate a molecular database (DNA Barcode) for entire fish species fauna in each small river/stream of Uttarakhand.  Using a combination of morphometric & DNA bar-coding data will provide an efficient method for species level identification and contributes considerably to taxonomic and biodiversity research. The present study is first step towards establishing molecular taxonomy database of Uttarakhand based upon the bar coding pattern of cytochrome c oxidase I (COI) gene.  We carried out an “entire river scan” of River Song (a tributary of river Ganges).  50 samples were collected from various sampling sites along the entire stretch of river and analyzed.   Data was uploaded into the BOLD database and the analysis of data using this database suggests that the genetic variability (K2P distance) distribution of 50 individuals belonging with 15 species.The average intraspecific variation using K2P and NJ methods/models was assessed. The mean intraspecific distance was less than 1.45% for 32% of species. Mean K2P distance within species, genus and family was 0.1%, 16.3% and 21.70% respectively. Our results suggest that River Song has diverse fish fauna with substantial genetic diversity.  Data from Barillius species suggests that this species has a very high variation.  There is ahighly probability that as all the rivers are scanned new data on endemic and exotic fish fauna diversity will emerge which would be helpful in conservation efforts.