The Limidae or file shells are members of the only family of bivalve molluscs in the suborder Limoida. The family includes 130 living species, assigned to 10 genera. Widely distributed in all seas from shallow to deep waters, the species are usually epifaunal or nestling, with many species building byssal nests for protection. The majority of species are capable of irregular swimming by waving their long mantle tentacles.