(order Primates, suborder Plesiadapiformes)
An extinct family of primates which lived during the Palaeocene and lower Eocene and are known mainly from fossils found in western N. America. Plesiadapis, which is typical, had ears and molar teeth reminiscent of those of lemurs, but the incisors were chisel-like, and the digits possessed claws rather than nails. It was a squirrel-like animal with fore and hind limbs of equal length. The plesiadapids represent an evolutionary branch which died out, and they are not ancestral to any of the higher primates.
Subjects: Zoology and Animal Sciences.