At about 3.5 mm (about 1/8 inch) in size, the Gem Cyclostreme, Arene tricarinata (Stearns, 1872) is one of the small gastropods found along the shores of the Southwest Florida. The species is one of the smallest members of the family Areneidae, a group of mollusks present in the world’s tropical and subtropical seas. The ending of the species name, tricarinata, derives from the Latin for “three-keeled,” an allusion to the spiral ridges present on the periphery (outer edge) of the shell.
The Gem Cyclostreme, Arene tricarinata, from Sanibel. Photos by José H. Leal.