Vertebrata Cuvier, 1812 - vertebrates
   Gnathostomata
     Teleostomi
       Class Osteichthyes Huxley, 1880 [paraphyletic] - bony fishes see [unranked] Euteleostomi
         Subclass Actinopterygii Woodward, 1891 - ray-finned fishes see Class Actinopterygii Woodward, 1891
           Infraclass Neopterygii Regan, 1923 see Subclass Neopterygii Regan, 1923
             Division Teleostei Müller, 1845 see Infraclass Teleostei Müller, 1845
               Subdivision Euteleostei Greenwood et al., 1966 see Cohort Euteleosteomorpha (Greenwood et al., 1966)
                 Superorder Acanthopterygii Rosen & Patterson, 1969 see [unranked] Acanthopterygii Rosen & Patterson, 1969
                   Series Atherinomorpha Greenwood et al., 1966 see Superorder Atherinomorphae (Greenwood et al., 1966)
                     Order Cyprinodontiformes Berg, 1940 - killifishes
                       Suborder Cyprinodontoidea see Suborder Cyprinodontoidei
                         1 Family Oryziatidae see Subfamily Oryziinae Rosen, 1964
                         2 Family Adrianichthyidae Weber, 1913
                         3 Family Horaichthyidae C.V. Kulkarni, 1940 see Subfamily Horaichthyinae (C.V. Kulkarni, 1940)
                         4 Family Cyprinodontidae Gill, 1865 - pupfishes
                         5 Family Goodeidae Jordan, 1923 - goodeids
                         6 Family Anablepidae Garman, 1895 - four-eyed fish
                         7 Family Nynsiidae Carroll, 1988, nom. null. see Family Jenynsiidae Günther, 1866
                         8 Family Poeciliidae Garman, 1895 - live-bearers