This paper contributes and provides additional information pertaining to the morphometrics, morphology, meristics characteristics, systematic classification, biology, distribution, country wise occurrence, ecological role, fishery status, life cycle, mating behavior, habits, habitats, human uses and their impacts on production systems and natural habitats in relation with biodiversity has been discussed with the clinical signs observed in the collected samples of Clarias gariepinus (Burchell, 1822) in seasonal swamp of Thoothukudi district, Tamil Nadu, India. Based on the opinion analysis from the fishers of swamps and calculated biodiversity indices shows the relative abundance of the fish species caught was relatively reduced with negative impact pertaining to biodiversity on the ecosystem.