Reproduction and growth of Littoraria (Gastropoda: Littorinidae) at Ang Sila, Thailand

Abstract

Little is known of reproductive patterns of molluscs inhabiting mangroves. Yet this is one of the dominant environments in tropical intertidal areas and molluscs are one of the dominant faunal groups in mangroves. Several species of the gastropod genus Littoraria are adapted specifically to life in mangrove environments. The present paper examines reproductive periodicity in four species of Littoraria from Ang Sila, Thailand, from June 2003 to June 2004. Monthly samples were made to measure reproduction and growth. Ripe or partly spawned animals occurred throughout study, suggesting that these species are capable of either partially spawning frequently or rapidly returning to reproductive condition after spawning. The major spawning occurred in August–September 2003 and January–February 2004. Littoraria pallescens had a clear growth pattern with a one-year life cycle. In contrast, there was apparent recruitment failure in L. melanostoma and the combination of L. articulata and L. strigata.