Proganochelys is the most primitive known turtle with a complete shell (possessing both a dorsal carapace and a ventral plastron), first appearing on Earth about 210 million years ago, during the late Triassic period and just after dinosaurs and mammals evolved. This anapsid was about 2 ft (60 cm) long, had a complete shell, was an omnivore and had no teeth.
It had a large ear-opening with a function that is not yet fully understood. Its neck was not retractile so it was protected by little spikes set in the skin. It also had a long tale protected by armoured spikes. Interpretations of the environment it lived combined with features of the limb morphology suggest that it occupied fresh water as a bottom walker but it was not exclusively aquatic or terrestrial. Fossils have been found in Germany and Thailand.