Arcidae -

: Maximum species diversity occurs in the Indo-West Pacific region, where over 180 valid species in more than 30 genera are recorded. Regional Presence : Tropical West Africa : ~27 species. West Atlantic : ~20 species. Northeastern Atlantic : ~10 species.

The family, commonly known as ark shells , is a diverse group of marine bivalve mollusks. These organisms are recognized by their distinct trapezoidal, ribbed shells and a taxodont hinge (characterized by many small, similar teeth). While primarily found in tropical and warm temperate shallow waters, they occupy a wide range of habitats—from coral reefs and rocky substrata to muddy estuarine environments. Taxonomy and Global Distribution arcidae

: A long, straight hinge line with numerous small teeth. : Maximum species diversity occurs in the Indo-West