The length of its body, excluding the tail, was approximately 65–75 centimeters, and it weighed around 7–9 kilograms.

The genus Pseudhyrax was first described in 1901 by Florentino Ameghino, based on fossil remains found in Argentina in terrains dated from the Late Eocene.

Pseudhyrax is traditionally considered a member of Archaeohyracidae, a clade of notoungulates sharing similarities with the modern rock hyrax, but larger in size and with hypsodont teeth.

The family Archaeohyracidae, however, may be paraphyletic, and some of its members may be basal to other groups of typotheres.

It was herbivorous and its high-crowned premolars and molars indicates that it was able to feed on hard and abrasive plants in open areas.