Smooth Venus Clam Shell, Chionista fluctigraga

Smooth Venus Clam, Chionista fluctifraga.  Shell collected from within the estuary of the Magdalena Bay complex, Baja California Sur, October 2018. Size: 3.9 cm (1.5 inches) x 3.4 cm (1.3 inches).

Smooth Venus Clam, Chionista fluctifraga (G.B. Sowerby II, 1853), is a Venus Clam of the Veneridae Family. They are also known as the Hard Shell Cockle. The shell is thick and somewhat inflated with a rounded triangular profile. They are equivalve (both valves equal in size and shape) with short siphons, three cardinal teeth at the hinge, and the anterior margin of the shell is lightly serrated. The exterior of the shell has both radial ribs and concentric ridges, with more pronounced radial ribs at the posterior end. The exterior of the shell cream or white in color and the interior is white, often with purple at both ends. Smooth Venus Clam Shells reach a maximum of 8.7 cm (3.4 inches) in length and 7.6 cm (3.0 inches) in height.

The Smooth Venus Clams live in shallow burrows within sand and mud substrate and depths up to 31 m (80 feet). They range from Southern California to Sonora, Baja California, and are found throughout the Sea of Cortez.

Synonyms include Chione gibbosula, Venus cortezi, and Venus fluctifraga.