Kingdom [Animalia] Linnaeus, 1758 - animals
   Subkingdom Metazoa Haeckel, 1874 see Kingdom Animalia Linnaeus, 1758
     Division Eumetazoa Butschli, 1910 see Subkingdom Eumetazoa Butschli, 1910
       Subdivision Bilateralia
         Phylum Chordata Bateson, 1885 - chordates
           Subphylum Vertebrata Cuvier, 1812 - vertebrates
             Superclass Pisces Linnaeus, 1758 - fishes
               Class Osteichthyes Huxley, 1880 - bony fishes see [unranked] Euteleostomi
                 Subclass Actinopterygii Woodward, 1891 - ray-finned fishes see Class Actinopterygii Woodward, 1891
                   Superorder Chondrostei Müller, 1844 see Subclass Chondrostei Müller, 1844
                     Order Acipenseriformes Berg, 1940 - sturgeons
                       Family Polyodontidae Bonaparte, 1835 - paddlefishes
                         Genus Polyodon Schneider, 1801
                         Genus Psephurus Günther, 1873