Bivalvia
Bivalvia, formerly known as the Lamellibranchiata and Pelecypoda, is a class of marine and freshwater molluscs characterized by their compressed bodies enclosed by a shell composed of two hinged parts. Bivalves, as a collective, lack a head and certain typical molluscan organs, such as the radula and the odontophore. Among the notable members of this class are the clams, oysters, cockles, mussels, scallops, and various other families inhabiting saltwater environments, along with several families found in freshwater habitats. The majority of bivalves are filter feeders, utilizing their evolved gills called ctenidia as specialized organs for both feeding and respiration. In order to evade predation, many bivalves bury themselves in sediment, while others cling to the seafloor or attach themselves to rocks and other rigid surfaces. Interestingly, certain bivalves like scallops and file shells exhibit the ability to swim, while shipworms are known for boring into materials like wood, clay, or stone, making them their habitat.
