Dimetrodon Rib
Age - 299 - 276 Million Years Old
Early Permian
Species - Dimetrodon
Specimen - Rib
Discovered - Archer County, Texas
(Measures 10' - Rib is in multiple pieces.)
 
- Dimetrodon 
Dimetrodon is an extinct genus of non-mammalian synapsid that lived during the Cisuralian, around 295–272 million years ago. It is a member of the family Sphenacodontidae. The most prominent feature of Dimetrodon is the large neural spine sail on its back formed by elongated spines extending from the vertebrae. It walked on four legs and had a tall, curved skull with large teeth of different sizes set along the jaws. Most fossils have been found in the Southwestern United States, the majority coming from a geological deposit called the Red Beds of Texas and Oklahoma. More recently, fossils have been found in Germany. Over a dozen species have been named since the genus was first erected in 1878.