Another local member of the widespread family Lucinidae, Stewartia floridana (Conrad, 1833) grows to about 28 mm (about 1.1 inch). The shell outline is circular, with a squarish, truncated posterior end. The shell surface is smooth, and the external sculpture consists of coarse, irregular growth lines. The thin, brownish periostracum (external, brownish layer) is present in well-preserved shells. Commonly found on the back-bay areas of Sanibel and Captiva.
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