Proganochelys is the oldest turtle species discovered to date, known only from fossils found in Germany and Thailand in strata from the late Triassic, dating to approximately 210 million years ago. It has several synonymns, including Chelytherium ("Turtle Beast"), Psammochelys ("Sand Turtle"), Stegochelys ("Roof Turtle") and Triassochelys ("Triassic Turtle"). Until relatively recently it was popularly known by the last name.