Diapsida Osborn 1903 [Laurin 1991] see Clade Diapsida Osborn 1903 [Gauthier & de Queiroz 2020]
Status: extant
   Archosauromorpha xxxHuene 1946 [Gauthier, Kluge & Rowe 1988] see Clade Archosauromorpha Huene 1946 [Benton 1985], nom. cl. inval.
  Status: extant
     Archosauria Cope, 1869
    Status: extant
       Ornithosuchia see [unranked] Avesuchia Benton, 1999
      Status: extant
         Ornithodira Gauthier 1986 see Clade Ornithodira Gauthier 1986 [M. Ezcurra, S. Nesbitt, M. Bronzati, F. Dalla Vecchia, F. Agnolin, R. Benson, ..., M. Langer 2020]
        Status: extant
           Dinosauria Owen 1841 [Padian & May 1993], nom. cl. inval. see Clade Dinosauria Owen 1842 [Langer, Novas, Bittencourt, Ezcurra & Gauthier 2020]
          Status: extant
             †Ornithischia Seeley 1887 [Padian & May 1993] see Order Ornithischia Seeley, 1887
            Status: fossil
               †Genasauria Sereno 1986
              Status: fossil
                 †Cerapoda Sereno, 1986 see Suborder Cerapoda Sereno, 1986
                Status: fossil
                   †Ornithopoda Marsh 1881 see Infraorder Ornithopoda Marsh, 1881
                  Status: fossil
                     1 Family †Heterodontosauridae Romer, 1966
                    Status: fossil
                     2 †Euornithopoda Sereno 1986
                    Status: fossil