Ark Shells of the Arcidae Family

Nine Ark Shells of the Arcidae Family can be found in this website:

The Arcidae Family (Lamark, 1809) are bivalve mollusks that Ark Shells which has one hundred eighty-nine species that have been placed in thirty genera. Ark Shells in the Arcidae Family differ from Ark Shells in the Noetidae Family in the placement of ligaments and the lack of striations on the ligaments.

Ark Shells are strongly ribbed having two symmetrical clam shells that look like an ark or treasure chest, from which they derive their common name. Their hinge line is arched and there are numerous teeth along the hinge line of both valves that align, like a zipper, when the shell is closed. Many Ark Sells are covered with a heavy periostracum (outer membrane), usually dark brown in color. Ark Shells can be found crawling along sand or mud, or they are attached to stones or rocks by byssus (thread-like anchor lines). The Ark Shells have a global distribution and are found from shallow to very deep waters. There are twenty-nine species of the Arcidae Family found along the various coastlines of the Baja Peninsula.