Order †Ornithischia Seeley, 1887
Parvorder †Genasauria Sereno, 1986
see Clade Genasauria Sereno 1986
Nanorder †Cerapoda Sereno, 1986
see Suborder Cerapoda Sereno, 1986
Hypoorder †Euornithopoda Sereno, 1986
see Clade Euornithopoda Sereno 1986
Suborder †Ornithopoda Marsh, 1871
see Infraorder Ornithopoda Marsh, 1881
Infraorder †Iguanodontia Dollo, 1888
see Clade Iguanodontia Dollo 1888
Gigafamily †Dryomorpha Sereno, 1986
see Clade Dryomorpha Sereno 1986 [D. Madzia, V.M. Arbour, C.A. Boyd, A.A. Farke, P. Cruzado-Caballero & D.C. Evans 2021]
Megafamily †Dryosauroidea Milner & Norman, 1984
see Family Dryosauridae Stefano, 1903
Genus †Valdosaurus Galton, 1977