Parent taxon: Testudinata according to O. P. Hay 1930
See also Andrews 1906, Gadow 1898, Hay 1902, Hay 1908, Perrier 1928 and Roxo 1937
Sister taxa: Amblypus, Ancyropus, Aplax oberndorferi, Athecae, Australochelyidae, Australochelys, Chelonipedidae, Chelycarapookus, Chelycarapookus arcuatus, Chelys blakii, Chengyuchelyidae, Chengyuchelys, Emydhipus, Emys neumayri, Emys paranensis, Eunotosauria, Heckerochelyidae, Helcura, Helochelydridae, Kallokibotion, Megasternon, Mesochelydia, Mongolochelyidae, Odontochelydia, Palaeochersis, Pappochelydia, Paracryptodira, Perichelydia, Platemys sehuensis, Platycheloides, Proganochelyidae, Proganochelys, Proterochersidae, Protochelys, Saltosauropus, Siamochelys, Testudines, Testudinites, Testudo elata, Testudo stricklandi, Testudofiexoolithidae, Testudoolithidae, Thalassochelydia, Tretosternon punctatum, Trionyx mammillaris
Subtaxa: Chelonioidae Chelydoidae Emydoidae Pleurosternoidae Thalassemydoidae Trionychoidae
Ecology: planktonic suspension feeder