First Report of Glauconome chinensis (Gray, 1828) from West Bengal-Odisha Coast, India

Abstract

The intertidal marine bivalve Glauconome chinensis (Chinese glauconome), Gray 1828 is a burrowing benthic fauna inhabiting in soft muddy to sandy sediments of Western pacific mangrove areas. The specimen is characterised by long siphon (inhalant and exhalent) for feeding and a prominent foot for locomotion. They are mostly gonochoric, few are sometimes protandric hermaphrodites. According to Gray’s description their embryonic development starts through free swimming trochophore larvae and succeeded by the veliger. Glauconome chinensis has been rediscovered for the first time from the intertidal coastal mangrove areas of Talsari, confluence of Subarnarekha estuary of West Bengal-Odisha coast, India. Quadrates having areas of 1m² were placed randomly on study sites and the studied specimens were unearthed, counted their size, biomas, population density and distribution pattern. Physico-chemical parameters were also evaluated. For anatomical study tissues were fixed in 4% formalin solution and processed through alcoholic grades. Body length, siphon, gill, mantle, foot, adductor muscles, digestive gland and gonads were examined. The studied specimens were stayed in 10-40cm depth from sediment surface and showed clumped distribution pattern. The mean length, width and biomass of the specimen were 39.2(mm) ±0.393, 14.5(mm) ±0.351and 3.89(gm) ±0.382 respectively.  The report on the occurrence of such intertidal bivalve adds relevant data for the good assessment of food chain and food web of marine coastal mangrove ecosystem. The present study also aims to gather knowledge of valuable ecological services of Glauconome chinensis and to maintain the biological integrity of West Bengal-Odisha coastal region with Bay of Bengal.