Order Testudines Wagler, 1830 - turtles Suborder Pleurodira Cope, 1864 Family Chelidae Gray, 1825 Subfamily Chelinae Gray, 1825 Genus Platemys Wagler, 1830 Platemys platycephala (Schneider, 1792) - twist-necked turtle Platemys platycephala melanonota Ernst, 1984 - black-backed twist-necked turtle