07/04/2026
The world's largest turtle to roam South America 10 million years ago was Stupendemys geographicus.
Stupendemys is an extinct genus of freshwater side-necked turtle belonging to the family Podocnemididae. It is the largest freshwater turtle known to have existed, with a carapace measuring over 2 meters (6.6 feet) in length.
Its fossils have been discovered in northern South America, in rock formations dating from the Middle Miocene to the early Pliocene, approximately 13 to 5 million years ago.
Male specimens are known to have possessed bony horns projecting from the front edges of their shells, and the discovery of a young adult fossil shows that the carapace flattened with age. A fossil skull described in 2021 also indicates that Stupendemys was a generalist feeder.
