Arcidae is a family of marine bivalves, commonly known as ark clams or angel wings. These bivalves are characterized by their triangular or elongated shells, which are often sculptured with radial ribs and concentric growth lines. They are filter feeders, living buried in the sand or mud and feeding on plankton and organic matter in the water. Arcidae species can be found in both shallow and deep waters, ranging from tropical to polar regions. Some examples of genera within this family include Barbatia, Arca, and Anadara.