Fishes show great diversity among all vertebrates. Proper identification of fishes is of great importance in evaluation of biodiversity. Morphometric method is one of the popular and oldest methods for identification of fishes. This method is now complemented with genetic identification method due to limitations of morphometric method. This new taxonomic methodology is an emerging trend in Pakistan. Molecular taxonomy as compared to morphometric taxonomy improves knowledge on the early life stages which could be u seful for both taxonomists and zoo technicians. With the growing population water, food and other resources are exploited greatly. This puts pressure on the aquatic environment and demands suitable conservation efforts. Purpose of present study is to apply DNA barcoding technique for identification of ichthyo -fauna of Indus River at Taunsa barrage. Present study involves Cytochrome C Oxidase1 gene for molecular identification of fish fauna of this region. This study resulted in total of 150 barcodes, which were differentiated into 30 taxonomically recognized species, 26 genera and 12 families. The mean length of all the sequences was 667 base pairs. The results were compared with the available literature of freshwater fish species in the River Indus. The average conspecific, congeneric and confamilial Kimura2 parameter (K2p) distances were .001%, .033% and .184% respectively. Biodiversity is shown by the clear differences in interspecific and intraspecific distances which are also found in the present work. From these results it is concluded that DNA barcoding can be used for biodiversity studies in different water bodies with positive results.
A total of 30 species belonging to 26 genera and 12 families were surveyed in this study. Fish species collected from the study area were preceded for the isolation of genomic DNA. The barcodes of mitochondrial CO1 gene, consisting of 650bp, were obtained by PCR amplification and sequencing. There were no stop codon, deletion and insertion sequences that support the view that the sequences belong to the amplified mitochondrial CO1 gene region. Moreover, the length of the amplified sequences larger than 600 bp also strengthened the idea that the obtained DNA sequences belong to mt DNA (Hubert et al., 2008). Two new species Glyptothorax telechiti and Captodon zilli were reported for the first time in Pakistan during this study.
The average conspecific, congeneric and confamilial Kimura2 parameter (K2p) distances were .001%, .033% and .184% respectively. Biodiversity is shown by the clear differences in interspecific and intraspecific distances which are also found in the present work
This study strongly concludes that DNA barcoding can work as a gateway for the identification of the fishes at species level. A short sequence of CO1 of mt DNA has sufficient variability among species can be used successfully as a base of the DNA barcoding.