Araeoscelida

Araeoscelidia or Araeoscelida is a clade of extinct tetrapods (traditionally classified as diapsidreptiles) superficially resembling lizards, extending from the Late Carboniferous to the Early Permian. The group contains the generaAraeoscelis, Petrolacosaurus, the possibly aquatic Spinoaequalis, and less well-known genera such as Kadaliosaurus and Zarcasaurus. This clade has historically been considered to be the sister group to all (currently known) later 'diapsids', though studies from the early 2020s onwards have found as among the earliest (if not the earliest) members of Sauropsida unrelated to neodiapsid reptiles, or even outside Sauropsida entirely, suggesting their physically diapsid skull is unrelated to those of modern diapsids.