Oyster

Oyster, bivalve mollusk of shallow coastal waters. While other bivalves are able to move by means of a muscular “foot,” oysters have lost this foot, and the animal lives cemented to a hard substrate of rocks or shells. Like all bivalves, oysters feed by removing suspended organic particles from a current of water drawn into the shell. Edible oysters are extensively fished and cultivated worldwide. The pearl oyster is a tropical species.