About Megapitaria squalida (G.B.Sowerby I, 1835)
Megapitaria squalida has thick, equally sized shell valves. When alive, the valves are covered by a grayish-brown periostracum. The outer surface of the shell is smooth, with a base color ranging from tan to brown, and it sometimes displays bands or speckles of varying color intensity. The interior of the shell is white, and sometimes has purple bands. Fully grown shells can reach 120 millimetres (4.7 in) in length, 97 millimetres (3.8 in) in width, and 68 millimetres (2.7 in) in depth. Live individuals can weigh up to 93 grams (3.3 oz). This species, commonly called the chocolate clam, is found in the eastern Pacific Ocean, ranging from Ojo de Liebre Lagoon in Baja California south to Mancora, Peru, and also occurs in the Gulf of California and the Galapagos Islands. Chocolate clams live buried in sandy sediments, ranging from the intertidal zone down to 160 metres (520 ft) deep. A study in Magdelena Bay recorded an average population density of 2.01 individuals per square meter, and larger individuals of this species are found in deeper water.
