Description

Early Permian

Arroyo Formation

Haskell county, TX, USA

0.35 inch toe bone. Pes phalanx 3, digit IV

Synapsid,

Ophiacodon is a genus of synapsid that lived during the Late Carboniferous and Early Permian.  Its remains have been found in various parts of the United States and one site in the United Kingdom.  Synapsids looked like reptiles but they represent a separate lineage that led to mammals with all their other representatives dying out by the Jurassic.  They included the top carnivores, such as Dimetrodon, and herbivores of the Permian.