Taxonomy and Systematics of the Fishes of 'Schistura denisoni' complex

The ‘Schisturadenisoni’complex was first described by Menon(1987). The complex is constituted by fishes which are morphologically similar toSchisturadenisoni Day, 1867 but shows genetically distinct identity. The fishes included in the complex has its centre of distribution in the rivers of Peninsular India. Many of the species which were included in the complex by Menon (1987) were resurrected from this synonymy and were subsequently redescribed as separate species. An integrative taxonomic investigation based on topotypic material, involving molecular analysis of mitochondrial Co1 gene reveals the difference in species identity among the specimen sampled from different locations. Although specimen belonging to different clades in the genus Schistura from the sampled rivers of peninsular India have a general appearance similar to Day’s material of S. denisoni (Day, 1867) from the type locality (i.e. Bhavani River), there are variations in the banding pattern as well as morphology of specimens from different localities. The molecular analysis of the samples collected from the different rivers (sampling sites) and the phylogenetic tree analysis signifies the observation of occurrence of different putative species in the‘Schisturadenisoni’ complex.