Southwest Florida Shells with Emphasis on Sanibel & Captiva
José H. Leal
Shell size to 150 mm; shell thick and heavy, usually narrow and elongate, but extremely variable in shape. Upper valve flatter, smaller than lower valve; lower valve convex. Shell outline variable. Shell margins usually undulating. Umbones long and curved. Color dirty- to light-gray, sometimes striped or flecked with brown, internally white with muscle scar deep purple. Lives attached to mangrove roots, rocks, other oyster shells. Species represent the northern counterpart of Crassostrea rhizophorae.