Terrapene carolina (Linneaus 1758) is the common box turtle, with the distinctive hinged plastron that permits it to completely enclose itself. Derived from a sister to Kayentachely, in the small sampling of turtles in the large reptile tree Terrapene is a sister to the green sea turtle, Chelonia.
Linnaeus C 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.