sunset shell

mollusk

Also known as: Tellinidae

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Last updated

July 14, 2026

Quick Summary

The term "sunset shell" refers to a type of marine clam belonging to the family Tellinidae. These clams are characterized by their equivalve shells, meaning both halves are equal in size and shape. The shells are often adorned with colorful bands that radiate outwards from the umbones, which are the oldest part of the shell. A "sunset clam" is another name for a sunset shell. These mollusks are marine bivalves known for their distinctive, colorful shells.12

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bivalve
External features
…brightly coloured, as in the Tellinidae. The shell is laterally compressed and thus more bladelike, but the adductor muscles are still of similar size (the isomyarian form). Such structural features adapt the animal for rapid movement through the sand; long siphons project to the surface above. Deep burrowing has been…
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…brightly coloured, as in the Tellinidae. The shell is laterally compressed and thus more bladelike, but the adductor muscles are still of similar size (the isomyarian form). Such structural features adapt the animal for rapid movement through the sand; long siphons project to the surface above. Deep burrowing has been…
Read More