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
               01 Genus Unio Philipsson, 1788
               02 Genus Uticosta Millard, 1996, orth. inval. see Genus Acuticosta Simpson, 1900
               03 Genus Afronaia Haas, 1962
               04 Genus Afroparreysia Haas, 1936
               05 Genus Arcidopsis Simpson, 1900
               06 Genus Arconaia Conrad, 1865
               07 Genus Cafferia Simpson, 1900
               08 Genus Canthyria Swainson, 1840
               09 Genus Caudiculatus Simpson, 1900
               10 Genus Chamberlainia Simpson, 1900
               11 Genus Chondrostes Gistl, 1850[1847] see Genus Unio Philipsson, 1788
               12 Genus Crassunio Modell, 1964
               13 Genus Ctenodesma Simpson, 1900
               14 Genus Cuneopsis Simpson, 1900
               15 Genus Diaurora Cockerell, 1903
               16 Genus Elongaria Haas, 1912
               17 Genus Haasodonta McMichael, 1956
               18 Genus Heudeana Frierson, 1922
               19 Genus Hyriopsis Conrad, 1853
               20 Genus Inversidens Haas, 1911
               21 Genus Lanceolaria Conrad, 1853
               22 Genus Leguminaia Conrad, 1865
               23 Genus Pseudoleguminaia Germain, 1911
               24 Genus Mesafra Haas, 1936
               25 Genus Middendorffinaia Moskvicheva & Starobogatov, 1973
               26 Genus Nephronaias Crosse & Fischer, 1894
               27 Genus Oxynaia Haas, 1913
               28 Genus Palindonaia Modell, 1950
               29 Genus Physunio Simpson, 1900
               30 Genus Pressidens Haas, 1910
               31 Genus Prisodontopsis Tomlin, 1928
               32 Genus Prolancealaria Moskvicheva, 1973
               33 Genus Prohyriopsis Haas, 1914
               34 Genus Pronodularia Starobogatov, 1970
               35 Genus Protunio Haas, 1913
               36 Genus Pseudoparreysia Woodward, 1965
               37 Genus Pseudopotomida Moskvicheva & Starobogatov, 1973
               38 Genus Ptychorhynchus Simpson, 1900
               39 Genus Scabies Haas, 1911
               40 Genus Schistodesmus Simpson, 1900
               41 Genus Solenaia Conrad, 1868
               42 Genus Unionetta Haas, 1955
               43 Genus Virgus Simpson, 1900