Diapsida Osborn 1903 [Laurin 1991] Archosauromorpha Huene 1946 [Gauthier, Kluge & Rowe 1988] see Clade Archosauromorpha Huene 1946 [Gauthier, Kluge & Rowe 1988] {Laurin 1991} Archosauria Cope, 1869 Ornithosuchia see [unranked] Avesuchia Benton, 1999 Ornithodira Gauthier 1986 Dinosauria Owen 1841 †Ornithischia Seeley 1887 see Order Ornithischia Seeley, 1887 †Genasauria Sereno 1986 †Cerapoda Sereno, 1986 see Suborder Cerapoda Sereno, 1986 †Marginocephalia Sereno 1986 †Pachycephalosauria Maryañska & Osmólska 1974 see Infraorder Pachycephalosauria Maryañska & Osmólska, 1974