Bivalves: Bivalvia - Coquina Clam (donax Variabilis): Species Accounts

Physical characteristics: The triangular valves are sculptured with ridges radiating out from center and come in white, yellow, orange, pink, purple, and blue. The inside surface of the valves is not pearly and is usually purple. The margins of the valves are finely toothed. Mature individuals grow up to 1 inch (25 millimeters) long.

Geographic range: They are found along the Eastern coast of North America from Chesapeake Bay to Florida and around the Gulf of Mexico to Yucatan.

Habitat: They burrow in sandy beaches that have wave action.

Coquina clams are found along the Eastern coast of North America from Chesapeake Bay to Florida and around the Gulf of Mexico to Yucatan. (© Harry Rogers/Photo Researchers, Inc.)

Diet: Coquina clams eat tiny plants and animals floating in the water.

Behavior and reproduction: They use their muscular foot to rebury themselves after being exposed by the waves and move up and down in the sand and along the beach.

Both males and females are required for reproduction. Eggs and sperm are released into the water, where fertilization takes place. They live up to two years.

Coquina clams and people: They are eaten in "coquina broth," and their shells are used for decorating gardens.

Conservation status: Coquina clams are not considered threatened or endangered. ∎