Definition: Scutachnids are a class of marine bivalves that primarily inhabit coastal areas, including estuaries and mangrove forests. They have four distinct groups: scuttanoids (scuttles), sponges, bivalves, and polychaetes. Scuttanoids include the common spiny scallop, which is a type of scallop with a hard shell made primarily from scuticulose material. Sponges are characterized by their unique structures
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