A review on freshwater fish diversity of India and concept of DNA barcoding in fish identification

Abstract

Fish contribute faintly more than one half of the total of vertebrates and India contributes to about 7.7% of global fish diversity. Fish and their diverse progressive phase sometimes find it difficult to recognize by morphological feature alone because of the high variety and phenotypic plasticity. Even within the species of fish, individual genetic distances may be found depending on the environmental stress and water quality which play an important role in its minor morphometric variations. There remains a need for taxonomic experts for single specimen identification. For less experienced user or non-specialist, it is difficult to identify the species which they encounter. Notably, DNA barcoding seems to be a more reliable approach for species identification, which is rapid and cost-effective. DNA barcode is based on the sequence divergence pattern of the cytochrome c oxidase I (COI) gene. DNA barcoding focuses on developing reference libraries of barcode sequence. FISH-BOL (Fish barcode of life) and international barcoding of life (iBOL.org) project is established as a reference DNA barcode library for all fishes. Recently, morphological analysis and DNA barcoding are conjointly used as a taxonomical approach for fish species identification. In this essence, the current review aimed to investigate the fish diversity and status of DNA barcoding of fish in India.