Order †Ornithischia Seeley, 1887
Count: -
   Parvorder †Genasauria Sereno, 1986 see Clade Genasauria Sereno 1986
  Count: -
     Nanorder †Thyreophora Nopcsa, 1915 see Suborder Thyreophora Nopcsa, 1915
    Count: -
       Hypoorder †Thyreophoroidea Nopcsa, 1928 see [unranked] Thyreophoroidea Nopcsa, 1928
      Count: -
         Minorder †Eurypoda Sereno, 1986 see Clade Eurypoda Sereno 1986
        Count: -
           1 Suborder †Stegosauria Marsh, 1877 see Infraorder Stegosauria Marsh, 1877
          Count: †1f;8g
           2 Suborder †Ankylosauria Osborn, 1923 see Infraorder Ankylosauria Osborn, 1923
          Count: -