DIVERSITY AND DISTRIBUTION OF AQUATIC INSECTS IN POND ECOSYSTEM IN CHEYYAR, THIRUVANNAMALAI DISTRICT OF TAMIL NADU, INDIA

Aquatic insects are the most diverse group of organisms in freshwater bodies such as lakes, ponds, rivers, streams, reservoirs, etc. A pond ecosystem is a body of standing water and very important habitats for so many various types of animals such as fishes, crustaceans, insects and amphibians. Aquatic insects are good bioindicators of water quality for assessment of pollution in short and long-term pollution events. The less or more aquatic insects are providing data to estimate the degree of environmental impact and its potential effects on other living organisms. In this study reveals diversity and distribution of aquatic insects from the pond ecosystem in the Kilpudupakkam, Cheyyar, Thiruvannamalai District for a period from August 2017 to January 2018. The aquatic insects were collected with the help of scoop net and hand nets. Later they were identified using of original literature. The insects identified for following 7 orders viz., Hemiptera, Coleoptera, Odonata, Ephemeroptera, Trichoptera, Diptera and Lepidoptera. Order Hemiptera (33.63%) is the largest population of pond ecosystem and compare with other orders and diversity indices were calculated. The order followed by Hemiptera were Coleoptera (27.21%), Odonata (14.98), Ephemeroptera (8.56%), Trichoptera (7.64%), Diptera (5.50%) and Lepidoptera (2.44%).