Arcidae -

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 belongs to the superfamily within the order Arcoida . It is a highly species-rich family, with a conservative estimate of over 300 extant species worldwide. arcidae

: Unlike most mollusks, Arcidae often contain hemoglobin in their hemocoel, giving them a red-colored body and the name "blood cockles". This adaptation may aid survival in low-oxygen environments like mud. The family, commonly known as ark shells ,

: A long, straight hinge line with numerous small teeth. Taxonomy and Global Distribution Arcidae belongs to the

: Though rare, some species are found at abyssal depths and in polar seas.