Above is an image of a soft-shelled turtle fossil called Trionyx sp. (Geoffroy Saint-Hilaire, 1809). This turtle fossil dates to the Eocene Epoch between 54.8 and 33.7 million years ago. It was found Fossil Lake, Wyoming, USA. The French naturalist Étienne Geoffroy Saint-Hilaire (1772–1844) named this genus in 1809.
The fossil was on display in the Evolving Planet section of The Field Museum of Natural History in Chicago Illinois, USA as of August 2020. Accession number is PF1600. They have an extensive collection of Fossil Lake fossils at the exhibit including holotypes.
