Casea is an extinct genus of pelycosaur synapsids which was about 1.2 metres (4 ft) long from Texas, United States and Aveyron, France. It was slightly smaller than the otherwise very similar Caseoides. Casea was one of the first amniote herbivores, sharing its world with animals such as Dimetrodon and Eryops. It was possibly also aquatic.[1]

Temporal range: Early Permian
Casea FMNH.jpg
C. broilii skeleton in the Field Museum of Natural History
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Clade: Caseasauria
Family: Caseidae
Genus: Casea
Williston, 1910
Type species
Casea broilii
Williston, 1910
Other species
  • C. halselli Olson, 1954
  • C. nicholsi Olson, 1954


Size relative to a human
C. broilii restoration

Casea had a heavy, round body and a small skull. Its rib cage was greatly expanded, presumably to make space for a large, plant-fermenting gut as well as proportionally large lungs. Like other caseids, it lacked teeth in its lower jaw, and had blunt teeth in the upper jaw. These adaptations indicate that Casea was a herbivore, feeding on relatively tough plants, such as ferns.[2] Like most derived caseids it had paddle-like limbs and osteoporotic bones, indicating adaptations for an aquatic lifestyle.[1] However, caseasaur fossils are typically found in upland environments and their anatomy would be unusual for a semiaquatic animal, so it is still disputed whether any caseasaurs were semi-aquatic.[3]


Casea was named in 1910 by the paleontologist S. W. Williston.[4] The genus name honors the paleontologist E. C. Case and the type species honors the paleontologist Ferdinand Broili.

See alsoEdit


  1. ^ a b Lambertz, Markus; Shelton, Cristen D.; Spindler, Frederik; Perry, Steven F. (2016). "A caseian point for the evolution of a diaphragm homologue among the earliest synapsids". Annals of the New York Academy of Sciences. 1385 (1): 3–20. doi:10.1111/nyas.13264. PMID 27859325.
  2. ^ Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 188. ISBN 978-1-84028-152-1.
  3. ^ Angielczyk, Kenneth D.; Kammerer, Christian F. (2018). "Non-mammalian synapsids: the deep roots of the mammalian family tree". In Zachos, Frank; Asher, Robert (eds.). Mammalian Evolution, Diversity and Systematics. Walter de Gruyter GmbH & Co KG. pp. 117–198.
  4. ^ Williston, S. W. (1910). "New Permian reptiles: Rhachitomous vertebrae". The Journal of Geology. 18 (7): 585–600. doi:10.1086/621786. JSTOR 30078133.