Full reference: O. P. Hay. 1930. Second Bibliography and Catalogue of the Fossil Vertebrata of North America 390(II):1-1074
Parent taxon: Reptilia according to O. P. Hay 1930
Sister taxa: Amblyglossae, Anapsida, Anhomoiichnium, Apatomerus, Archaeosauria, Atremata, Chelydosauria, Cunichnoides, Dimetropus, Diplotremata, Dipnoa, Dolichobrachium, Dravidosaurus, Dravidosaurus blanfordi, Embolophorus, Enaliosauria, Eureptilia, Glauconia, Holosauria, Hyperosauria, Ichthyosaurus inexpectatus, Ischyrotherium, Isocampe, Kintneria, Lyognatha, Macelognatha, Metamosaurus, Monopnoa, Monotreta, Monozygocrotapha, Onychichnium, Oolithes, Ornithocephala, Pantestudines, Parareptilia, Pessopteryx arctica, Pessopteryx pinguis, Placodontomorpha, Plesiosaurus doedicomus, Polemarchus, Proganosauromorpha, Proreptilia, Prosauria, Protorosauria, Puercosaurus, Puercosaurus obtusidens, Rhamphosauria, Rhizodonta, Rhynchosauroidae, Saurichthys indicus, Saurophidia, Seps, Sillimanius, Squamata, Steropoides, Streptosauria, Svalbardosaurus, Svalbardosaurus crassidens, Testudinata, Theromorpha, Tocosauria
Subtaxa: Astatoglyptica Catacritosauria Elpidosauria
Ecology: