The Plicatulidae are a family of saltwater clams, marine bivalve mollusks, known commonly as kitten's paws or kittenpaws.[1] These bivalves are related to oysters and scallops. The family has a single living genus, Plicatula, with a second, Harpax known from fossils.
Plicatulidae are small, with weakly convex shells which are irregularly oval or even almost triangular. Typically, they attach themselves to a hard surface by the right valve. The ligament is internal and triangular.