Infraphylum Tetrapoda Goodrich, 1930 see Clade Tetrapoda Hatschek & Cori 1896 [Laurin 2020]
   Superclass Amniota Haeckel, 1866 see Clade Amniota Haeckel 1866 [Laurin & Reisz 2020]
     Paraclass Reptilia Linnaeus, 1758 [paraphyletic] - reptiles
       Parasubclass Diapsida Osborn, 1903 [paraphyletic] - diapsids see Clade Diapsida Osborn 1903 [Gauthier & de Queiroz 2020]
         Parainfraclass Archosauria Cope, 1869 [paraphyletic] see Clade Archosauria Cope 1869 [Gauthier & Padian 2020]
           Superorder †Ornithischia Seeley, 1887 see Order Ornithischia Seeley, 1887
             Order †Ceratopsia Marsh, 1890 see Infraorder Ceratopsia Marsh, 1890
               Family †Ceratopsidae Marsh, 1888
                 Parasubfamily †Eucentrosaurinae Olshevsky, 1991, nom. illeg. [paraphyletic] see Subfamily Centrosaurinae Lambe, 1915
                   1 Genus †Avaceratops Dodson, 1986
                   2 Genus †Brachyceratops Gilmore, 1914
                   3 Genus †Eucentrosaurus Chure & McIntosh, 1989, nom. illeg. see Genus Centrosaurus Lambe, 1904
                   4 Genus †Monoclonius Cope, 1877, nom. dub.
                   5 Genus †Pachyrhinosaurus Sternberg, 1950
                   6 Genus †Styracosaurus Lambe, 1913