Procolophonidae
Procolophonidae is an extinct family of parareptiles from the Permian and Triassic periods.
They were shaped like stocky lizards, with broad-cheeked skulls. Their cheeks sported a stout backward-pointing spike. Hypsognathus, from North America, had many cheek spikes. Procolophon, the genus after which the group was named, is unusual. Their skulls resemble the turtles', sharing a posttemporal fenestra. Accordingly, they have historically been classed alongside the turtles under the Anapsida.
Up to the early Triassic, their teeth were sharp, indicating an insectivorous diet. Later in the Triassic their teeth became broader, indicating a switch to a herbivorous diet. They became extinct at the end of the Triassic.
Discoveries announced in 2008 suggest that these animals may have lived in Antarctica in the Early Triassic, and were thus among the earliest tetrapods in the Antarctic.
Phylogeny
Below is a cladogram from Ruta et al. :
