Ancylocoelus

Ancylocoelus is an extinct genus of mammal, belonging to the order Notoungulata. It lived during the Late Oligocene, in what is today Argentina, in South America.

Description
This genus is only known from cranial remains, but comparison with some of its better-known relatives such as Leontinia indicates that it was an heavily shaped animal, vaguely similar to an hornless, smaller and slender rhinoceros. The skull was short and tall, with low-crowned (brachydont) premolars and molars. Ancylocoelus was approximately 1.70 meters long and 70 centimeters high at the withers. Compared to other, more basal forms, Ancylocoelus lacked both its upper and lower canines, and its first lower premolar.

Classification
Ancylocoelus was first described in 1894 by Florentino Ameghino, based on fossil remains found in Argentina. The type species is Ancylocoelus frequens. A few years later Ameghino described two other species, A. lentus and A. minor.

Ancylocoelus was a member of the family Leontiniidae, a group of Notoungulates with heavy shapes, typical of the South American Oligocene. It was closely related to Leontina and Scarrittia.