This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: "Stylemys" – news · newspapers · books · scholar · JSTOR (April 2008) (Learn how and when to remove this template message)

Temporal range: late Eocene to early Oligocene
Stylemys (1).jpg
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Suborder: Cryptodira
Superfamily: Testudinoidea
Family: Testudinidae
Genus: Stylemys
Leidy 1851

Stylemys (meaning "pillar turtle") is the first fossil genus of dry land tortoise belonging to the order Testudines discovered in the United States. The genus lived in temperate to subtropical areas of North America, Europe, and Asia, based on fossil distribution.[1] The genus was first described in 1851 by Joseph Leidy.[2] The tortoise was common in the prehistoric Badlands, especially Nebraska and South Dakota. The species has also been found in the formations in and around Badlands National Park. Fossil fragments have also been found in the Palm Park Formation of New Mexico.[3]

The ancient tortoises had primitive jaw muscles, unlike today's tortoises, which also display the os transiliens bone, and would have been herbivorous. While Stylemys species did exhibit the same neck structure as modern tortoises, the forelimbs were unsuitable for burrowing, setting them apart from modern genera.


A number of species have been described since the genus was named in 1851.[4]

Time period

Eon: Phanerozoic Era: Cenozoic Period: Paleogene Epoch: Eocene


  1. ^ Auffenberg, Walter (1964). "A Redefinition of the Fossil Tortoise Genus Stylemys Leidy". Journal of Paleontology. 38 (2): 316–324. JSTOR 1301552.
  2. ^ Leidy, J. (1851). "Description of Stylemys nebrascensis". Proc. Acad. Nat. Sci. Phila. 5: 172–173.
  3. ^ Lucas, Spencer G.; Williamson, Thomas E. (1993). "Eocene vertebrates and late Laramide stratigraphy of New Mexico". New Mexico Museum of Natural History and Science Bulletin. 2: 145–157. Retrieved 2 August 2020.
  4. ^ The Paleobiology Database