Gametogenic Phenology in Freshwater Molluscan Species; Lamellidens Marginalis and Parreysia Corrugata.

Annual reproductive cycle of the freshwater uninoid bivalves Lamellidens marginalis and Parreysia corrugata from Panchganga river, Maharashatra, India were studied for period of June, 2010 to May, 2011. Monthly sample of 10 individuals of both the species were collected and subjected to germinal cell count along with shell size distribution and evaluation of sex ratio. Histological observations of gonadal cells were conducted, to understand the gametic physiology. Gametogenic proliferations in male and female bivalves were quantified to determine gonadal maturation in the species. Germinal cells were correlated with the environmental parameters, to understand its impact over reproductive mechanism in freshwater uninoid bivalve molluscs. Comparative data of phenological alterations in physiology of reproduction was analyzed and quantified statistically using ANOVA. Phenological gametogenic cycle of Lamellidens marginalis showed advancement in breeding behavior, in comparison to prolonged gametogenetic behavior of Parreysia corrugata.