Parareptilia
Extinct subclass of reptiles
Parareptilia ("near-reptiles") is an extinct subclass of basal sauropsids ("reptiles"). Traditionally considered the sister taxon to Eureptilia (the group that likely contains all living reptiles and birds), its validity as a monophyletic clade has been disputed by modern cladistic analyses. "Parareptiles" first arose near the end of the Carboniferous period and achieved their highest diversity during the Permian period.
From Wikipedia, under CC BY-SA. More on occurri.