| The zooplankton are very sensitive to the environment where they live; so, any change in the environment may leads to change in the zooplanktonic communities in terms of tolerance, abundance, diversity and dominance in the habitat. They are of primary importance of aquatic food chain and are also good bio-indicators of aquatic environment. The present study was conducted during 2015 based on some local surveys conducted to water bodies in and around Chennai district of Tamil Nadu. Nearly 35 lots of zooplankton samples were collected. A total of 54species of zooplanktonic organisms belonging to the different groups viz. Protozoa: Rhizopoda, Rotifera, Cladocera and Ostracoda were identified. Rhizopods belonging to 7 species, 1 order, 5genera under 4families; 16 species of Rotifers belonging to8 genera, 2 orders, under 6 families; Cladocerans belonging to 17 species, 9 genera, 2 orders under 5 families and Ostracods belonging to 14 species, 9 genera, 1 order under 1 family were recorded during the present study. Cladocerans were the dominated group followed by Rotifers, Ostracods and Rhizopods. The polymorphic forms of the Rotifer Brachionuscalyciflorus viz. Brachionuscalyciflorus f. amphicerosand Brachionuscalyciflorus. f. borgeti were also recorded. The study reports several alkaline - eutrophic indicators also. |