Permian Synapsid Sail Spine
Age - 299 / 270 Million Years Old
Species - Edaphosaurus
Specimen - Sail Spine
Discovered - rcher County Texas, Archer City Formation
 
- Edaphosaurus 
Edaphosaurus is a genus of extinct edaphosaurid synapsids that lived in what is now North America and Europe around 303.4 to 272.5 million years ago, during the late Carboniferous to early Permian periods. American paleontologist Edward Drinker Cope first described Edaphosaurus in 1882, naming it for the "dental pavement" on both the upper and lower jaws, from the Greek edaphos έδαφος and σαῦρος.