Full reference: E. D. Cope. 1880. The skull of Empedocles. The American Naturalist 14:304
Parent taxon: Batrachosauria according to M. Laurin and R. R. Reisz 1995
See also Broom 1913, Carroll 1967, Carroll 1969, Colbert and Kitching 1975, Daly 1973, Gauthier et al. 1988, Gow 1977, Haubold 1971, Haubold 1974, Haughton and Brink 1954, Hay 1902, Hay 1930, Heaton 1979, Jaekel 1911, Kuhn 1946, Kuhn 1966, Lavina 1983, Lewis and Vaughn 1965, Osborn 1903, Osborn 1903, Osborn 1904, Romer 1956, Roxo 1937, Stovall 1950, Swinton 1934 and Williston 1917
Sister taxon: Seymouriamorpha
Subtaxa: Amniota Archeria Bathyglyptus Captorhiniformes Captorhinomorpha Chamasaurus Conodectiformes Datheosauri Diadectiformes Diadectomorpha Diadectosauria Gilmoreichnus Gymnarthriformes Labidosauria Limnoscelia Pantyliformes Pantyloidea Pareiasauriformes Procolophonipus Sauraviformes Solenodonsauridae Tomicosaurus Trilophosauria Varanopus