Trigoniidae

Trigoniidae
Trigonia sp. (Cretaceous) near Austin, Texas. Scale bar is 10 mm.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Bivalvia
Order:	Trigoniida
Superfamily:	Trigonioidea
Family:	Trigoniidae Lamarck

Trigoniidae is a taxonomic family of saltwater clams, marine bivalve mollusks in the superfamily Trigonioidea. There is only one living genus, Neotrigonia, but in the geological past this family was well represented, widespread and common. The shells of species in this family are morphologically unusual, with very elaborate hinge teeth, and the exterior of the shell is highly ornamented.