Casea

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. Casea had a heavy, round body and a small skull. Its rib cage was greatly expanded, presumably to make space for a large, plant-fermening 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. Like most derived caseids it had paddle-like limbs and osteoporotic bones, indicating adaptations for an aquatic lifestyle. 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 semiaquatic. Casea was named in 1910 by the paleontologist S. W. Williston. The genus name honors the paleontologist E. C. Case and the type species honors the paleontologist Ferdinand Broili.