Preliminary Study on the Mangrove-Associated Molluscan Diversity of Ashtamudi Lake, Kerala, India

A preliminary study on the mangrove associated molluscan diversity, distribution and seasonal variation of Ashtamudi Lake in Kollam District, Kerala revealed the presence of 42 species belonging to 38 genera under 23 families and 2 classes (Gastropoda and Bivalvia). The species diversity was highest in class Bivalvia (28 species) followed by Gastropoda (14 species). The class Bivalvia was represented by 16 families, 26 genera, and 28 species and class Gastropoda was represented by 7 families, 12 genera and 14 species. In bivalves, Mytilidae and Veneridae were found to be the dominant bivalve molluscan families and Neritidae was observed to be the dominant gastropod family comprising of four species. Among these, the bivalve mollusc Mytellastrigata and gastropod mollusc Pirenellac ingulata were found to be the most dominant species in these backwaters. Both distribution and diversity peaked during the post-monsoon season followed by the pre-monsoon season and decreased during the monsoon season.