Pacific Turkey Wing Shell, Arca pacifica

Pacific Turkey Wing Shell, Arca pacifica. Size: 4.0 cm (1.6 inches) x 1.9 cm (0.7 inches).  Shell collected off the beach at Km 26, Cero Colorado, Baja California Sur, March 2010.

The Pacific Turkey Wing, Arca pacifica (G.B. Sowerby I, 1833), is a bivalve mollusk that is a member of the Arcidae Family of Arks. They are known in Mexico as arca concha and arca chuchoca. The shell is somewhat variable in shape, but are generally oblong, with a broad, flat surface on the hinge side. The beaks are separated by this surface. There is a gap along the valve margin. Young specimens are white with beautiful brown to violet brown streaks. Older shells are grayer and have a rougher surface. The shell is usually covered by a thick, brown periostracum. The Pacific Turkey Wing reach a maximum of 15.6 cm (6.1 inches) in length and 7.4 cm (2.9 inches) in height.

Pacific Turkey Wings are found attached rocks, in the intertidal zone to depths of 137 m (450 feet). They range throughout the Sea of Cortez and from Magdalena Bay, Baja California Sur, south to Peru, including the Cocos, Galapagos, and Revillagigedo Islands.

A synonym is Byssoarca pacifica.