Amathusia Venus Clam Shell, Chionopsis amathusia

Amathusia Venus Clam Shell, Chionopsis amathusia. Shell collected off the beach at Punta Chivato, Baja California Sur, May 2022. Size: 5.4 cm (2.1 inches) x 5.1 cm (2.0 inches) x 2.3 cm (0.9 inches). Collection, photograph and Identification courtesy of Colin Campbell, DVM, Punta Chivato, Baja California Sur.

The Amathusia Venus Clam, Chionoipsis amathusia (Philippi, 1844), is a bivalve mollusk that is a member of the Veneridae Family of Venus Clams. They are known in Mexico as almeja. The shell is strong, inflated, and sturdily-built. The exterior of the shell has fine sculpture with inter-ribs between the primarily radial ribs with concentric lamellae raised into prickly scales. The exterior is light brown; the interior is off-white. They are covered with a light-brown thin, velvety periostracum. Amathusia Venus shells reach 7.4 cm (2.9 inches) in length, 6.3 cm (2.5 inches) in height.

Amathusia Venus Clam shells reside in sand substrate, intertidally, and to depths of 75 m (250 feet). The majority of shells are collected as beach wash-ups. They are found throughout the Sea of Cortez and along the west coast of the mainland south to Guatemala.

Synonyms include Chione jamaniana, Venus anathusia and Venus darwinii.