New Distributional Record and Habitat Preferences of the Isognomon ephippium (Linnaeus, 1758) Along Odisha Coast, Bay of Bengal

This study highlights the range extension of the marine bivalve species Isognomon ephippium from Chilika Lagoon to the Bahuda Estuary (Sonepur) and Haripur Creek (Gopalpur) along the south Odisha coast, observed during December 2024. Previously, this species was recorded in the outer channel region of Chilika. Notably, specimens from the Bahuda Estuary were larger in size as compared to those from the Haripur Creek. However, in the Haripur Creek region Isognomon ephippium was found attached over the plastic debris, which is not yet reported. Additionally, the presence of marine biofouling community on the bivalve shell, along with gastropod egg capsules, has been more intensely observed in the specimen from the Bahuda Estuary. Furthermore, the presence of a nacreous (pearl-producing) layer in these oysters suggests their potential for pearl culture. Establishing a scientifically managed and sustainable marine pearl culture industry could provide an additional livelihood opportunity for local fisheries. This finding offers new insights into the need for reassessing marine species diversity in response to both natural and human-induced environmental changes.