Nucula

mollusk genus

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July 1, 2026

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The genus Nucula refers to a type of marine bivalve mollusk, often called a "nut shell" due to its small, nut-like shell. These mollusks are characterized by their equivalve shells (both halves are equal) and large labial palps used for feeding. Nucula belongs to the subclass Protobranchia, considered a primitive bivalve ancestor, and is known for its unique feeding mechanism where labial palps collect and sort organic material from the sediment. They burrow close to the sediment surface and have a distinctive shell shape that is rounded at the front and pointed at the back.12345

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bivalve
Internal features
Nucula, from the subclass Protobranchia, reflects the primitive bivalve ancestor. Burrowing close to the sediment surface, Nucula is equivalve, anteriorly and posteriorly symmetrical, and isomyarian. The medial foot is wide. There are no mantle fusions ventrally, and the aerating water current passes through the mantle…
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Nucula, from the subclass Protobranchia, reflects the primitive bivalve ancestor. Burrowing close to the sediment surface, Nucula is equivalve, anteriorly and posteriorly symmetrical, and isomyarian. The medial foot is wide. There are no mantle fusions ventrally, and the aerating water current passes through the mantle…
Read More