Class Bivalvia Linnaeus, 1758 - bivalves
Subclass Autobranchia Grobben, 1894
Superorder Heteroconchia Gray, 1854
Clade Palaeoheterodonta Newell, 1965
Order Unionida Gray, 1854
Superfamily Unionoidea Rafinesque, 1820
1 Family Unionidae Rafinesque, 1820 - pearly mussels
2 ?Family †Liaoningiidae Yu & Dong, 1993, nom. illeg.
3 Family Margaritiferidae Henderson, 1929 (1910), nom. cons. - freshwater pearl mussels
4 Family †Sancticarolitidae Simone & Mezzalira, 1997