Protorothyrididae is an extinct family of small, lizard-like reptiles. Their skulls did not have fenestrae, as is also true of modern turtles and tortoises. Protorothyridids lived from the Late Carboniferous to Early Permian periods, in what is now North America. Many genera of primitive reptiles were thought to be protorothyridids. Brouffia, Coelostegus, Paleothyris and Hylonomus, for example, were recently found to be more basal eureptiles.