Stratigraphic chart of the lower Permian (partial)
Content updated October 16, 2005
RICHARDS SPUR UNIDENTIFIED
PELYCOSAUR
Above: picture in anterior view of the same vertebra of note are the strongly medially tilted zygapophyses, it seems a sphenacodontid vertebra except for the fact that the zygapophyses extend greatly laterally beyond the centrum margin.