Heteroconchia is a taxonomic infraclass of diverse bivalve molluscs, belonging to the subclass Autobranchia.

[1] This infraclass includes the cockles, Venus clams,[1] the freshwater mussels, brooch clams, as well as Heterodonta and Archiheterodonta.

[2] These bivalves are distinguished by having the two halves of the shell equally sized (i.e, they are equivalved) and having a few cardinal teeth separated from a number of long lateral teeth.

Their shells lack a nacreous layer, and the gills are lamellibranch in form.

[3] The following tree is their info which has been updated with the latest information from the World Register of Marine Species:[1] Infraclass: Heteroconchia