Phylum Mollusca Linnaeus, 1758 - molluscs
Class Bivalvia Linnaeus, 1758 - bivalves
Subclass Palaeoheterodonta Newell, 1965
see Clade Palaeoheterodonta Newell, 1965
Order Unionida Gray, 1854
Superfamily Unionoidea Rafinesque, 1820
Family Unionidae Rafinesque, 1820 - pearly mussels
Subfamily Unioninae Rafinesque, 1820
Genus Physunio Simpson, 1900
Subgenus Velunio Haas, 1914