Biodiversity of marine mollusc from selected locations of Andhra Pradesh coast, South eastern India

842-855Study on the diversity of molluscan fauna was carried out in eight locations along Andhra Pradesh coast. 70 species of mollusc including 44 species of Gastropods, 23 species of Bivalves and 3 species of Cephalopods were collected and documented. Shannon-Wiener diversity index (H') of Gastropods, Bivalves and Cephalopods ranged from 1.36 to 1.47, 1.11 to 1.21 and 1.06 to 1.43 respectively and Pielou’s Evenness index ranged from 0.90 to 0.94, 0.90 to 0.96 and 0.35 to 0.92 respectively. Total percentage varies within the class Gastropoda, Bivalvia and Cephalopoda. Gastropod existed with highest range of 60% followed by Bivalvia with 32 % and the lowest range existed to be the Cephalopods with 8%. Fishers α range varied from 0.44 to 7.22. Brillouin index range varied between 1.06 and 3.42. Among the eight locations, total density was observed higher in Location II (Vadrevu) with 15.12% and least density range in Location 8 (Nellore harbour) with 7.67% as this study site was highly polluted due to anthropogenic activities near harbour. Umbonium vestiarium, Cerithidea cingulata were observed to be the dominant and maximum in numbers and the bivalves Perna viridis and Donax faba were found to be maximum in diversity