Alternative spellings: Ornithopeda, Ornithopodi, Ornitophoda
Synonym: Ornithopodoidea Nopcsa 1929
Full reference: O. C. Marsh. 1881. Principal characters of American Jurassic dinosaurs. Part V. The American Journal of Science and Arts, series 3 21:417-423
Parent taxon: Cerapoda according to P.-E. Dieudonné et al. 2020
See also Agnolín et al. 2023, Anderson and Cruickshank 1978, Apesteguía et al. 2012, Arldt 1909, Baird and Horner 1979, Bakker 1986, Bakker and Galton 1974, Battail 1986, Baur 1887, Benton 1979, Benton 1990, Bonaparte 1978, Buchholz 2002, Buscalioni and Sanz 1987, Butler et al. 2007, Butler and Sullivan 2009, Butler et al. 2008, Campione and Evans 2011, Carroll 1988, Charig 1967, Chure et al. 2006, Cooper 1985, Coria et al. 2012, Cruzado-Caballero et al. 2010, Delair 1960, Dollo 1882, Dollo 1884, Dollo 1885, Dong 1989, Dong et al. 1983, Escaso et al. 2014, Estes 1964, Freedman Fowler and Horner 2015, Gadow 1897, Gadow 1898, Gadow 1901, Gasulla et al. 2015, Gegenbaur 1898, Godefroit et al. 1998, Han et al. 2012, Hatcher 1901, Haubold 1971, Haughton and Brink 1954, Hay 1902, Herne et al. 2019, Herne et al. 2018, Huene 1908, Huene 1909, Huene 1914, Huene 1927, Huene 1948, Huene 1954, Huene 1958, Ibiricu et al. 2019, Ibiricu et al. 2021, Kobayashi et al. 2019, Krebs 1974, Kuhn 1946, Kuhn 1964, Kuhn 1966, Lapparent 1947, Lapparent 1960, Lull 1912, Lull 1924, Lydekker 1888, Madzia et al. 2018, Mansel-Pleydell 1902, Marsh 1881, Marsh 1882, Marsh 1884, Marsh 1885, Marsh 1894, Marsh 1895, Marsh 1896, Martinelli and Forasiepi 2004, Maryanska and Osmólska 1985, Matthew 1915, McGinnis 1982, McIntosh 1981, Meunier 1883, Miller 1967, Moyano-Paz et al. 2022, Nopcsa 1923, Norman 1984, Novas et al. 2019, Novas et al. 2004, Ostrom 1965, Ostrom 1980, Parsch 1963, Peng et al. 2001, Perrier 1928, Prieto-Márquez et al. 2019, Quenstedt 1882, Rauhut 2003, Romer 1956, Romer 1966, Roxo 1937, Russell 1984, Sánchez-Hernández et al. 2007, Sauvage 1896, Sauvage 1898, Sauvage 1900, Sauvage 1914, Sereno 1986, Sereno 1997, Sereno 1998, Sereno 1999, Shibata et al. 2011, Simmons 1965, Sternberg 1953, Sternberg 1954, Swinton 1934, Swinton 1936, Swinton 1970, Tatarinov 1964, Thulborn 1977, Thurmond and Jones 1981, Van Den Broeck 1900, Wang et al. 2017, Weishampel 2004, Weishampel and Weishampel 1983, Winkler 1893, Woodward 1898, Xu et al. 2018, Zhang et al. 2019, Zhao 1983, Zheng et al. 2012 and Zittel 1890
Sister taxa: Chasmatopia, Marginocephalia
Subtaxa: Ampelognathus Anomoepodidae Bonaparteichnium Brachypoda Burianosaurus Camptosaurichnus Camptosauropus Changchunsaurus Changmiania Clypeodonta Dakotasaurus Dinosauropodes Dolichopoda Euornithopoda Fabrosauria Gideonmantellia Gilmoreosaurus arkhangelskyi Goseongosauripus Hypsiloichnus Iguanodontipodidae Iguanodontipodidae Jiayinosauropus Kalodontoidea Laosaurus Laosaurus celer Laosaurus minimus Moyenisauropodidae Nanosaurus Ningxiapus Ornithopoidea Othnielia Phyllodon Psilotrisauropus Qantassaurus Siluosaurus Taponichnus Telosichnus Tetrapodosauridae Trachodontoidea Unespichnium Walmadanyichnus Weewarrasaurus Wintonopus