Archaeopithecidae

The family Archaeopithecidae is only represented by two uncommon Casamayoran taxa.  They are relatively small animals, the specimens below measuring approximately 4 cm in length.

Upper (left)  and lower (right)  dentition of Acropithecus rigidus (from Simpson, 1967).  The specimen on the left is a left maxilla in occlusal (upper) and labial (lower) views.  The specimen on the right is a left mandible in occlusal (above) and labial (below) views.

The name Archaeopithecus ("ancient ape") perhaps alludes to the very superficial resemblance of the skull of these animals to that of some fossil primates.  As Simpson (1984) pointed out, Florentino Ameghino (the pioneering South American paleontologist who described more South American taxa than any other researcher) believed all groups of modern mammals originated from South American groups; these beliefs were often reflected in the names of the taxa he described, such as Archaeopithecus, Notohippus ("southern horse"), and Archaeohyrax ("ancient hyrax"). Representative Taxa   Order Notoungulata     Suborder Typotheria       Family Archaeopithecidae:  Archaeopithecus, Acropithecus