Dinosauria Owen 1841 [Padian & May 1993], nom. cl. inval. see Clade Dinosauria Owen 1842 [Langer, Novas, Bittencourt, Ezcurra & Gauthier 2020]
   †Ornithischia Seeley 1887 [Padian & May 1993] see Order Ornithischia Seeley, 1887
     †Genasauria Sereno 1986
       †Neornithischia Cooper 1985
         †Marginocephalia Sereno 1986
           †Ceratopsia Marsh 1890 see Infraorder Ceratopsia Marsh, 1890
             †Neoceratopsia Sereno 1986
               Genus †"Chaoyoungosaurus" Zhao, 1983, nom. nud. see Genus Chaoyangsaurus Zhao, Cheng & Xu, 1999