Full reference: E. C. Olson. 1947. The Family Diadectidae and its Bearing on the Classification of Reptiles. Fieldiana: Geology 11(1):1-53
Parent taxon: Reptilia according to M. Laurin and R. R. Reisz 1995
Sister taxa: Amblyglossae, Anapsida, Coeluria, Cunichnoides, Enaliosauria, Eupalamopus, Eureptilia, Ganocephala, Glauconia, Gymnarthria, Ichthyopterygia, Ischyrotherium, Isocampe, Kintneria, Macelognatha, Omosauria, Oolithes, Ornithocephala, Placodontomorpha, Plectropterna, Proganosauromorpha, Pythonomorpha, Rhamphosauria, Rhizodonta, Sauranodonta, Streptosauria, Testudinata, Theromorpha, Tocosauria, Triaenopus
Subtaxa: Ankyramorpha, Bolosauridae, Cheloniamorpha, Delorhynchus, Diadecta, Eunotosaurus, Microleter, Millerettidae, Procolophonomorpha
Ecology: