12.7" Titanothere (Megacerops) Upper Jaw - South Dakota

Titanothere (Megacerops) Upper Jaw - South Dakota #92712

This is a 12.7" long upper jaw of a massive Titanothere, a Rhinoceros-looking animal that lived during the Late Eocene. It was collected from the Eocene aged Chadron Formation of South Dakota. There are three molars present in the jaw. Upper jaws tend to be much more desirable among collectors than the lower jaws because the molars are much wider and just generally more massive.

Some of the teeth have undergone restoration to the dark enamel. The deep-brown/black spots on these teeth are locations where restoration has occurred and are best viewed under longwave UV light. Portions of this specimen have also undergone gap fill in cracks and around one side of the teeth to assist with structural integrity of the entire jaw. The teeth have not been remounted like some jaw sections from this location.

Artist's reconstruction of a Titanothere. By Nobu Tamura (http://spinops.blogspot.com)

Titanotheres were a massive mammal that lived during the Eocene. While they closely resembled modern rhinoceroses, they were actually more closely related to modern horses. They first appeared in the Early Eocene, about 54 million years ago, and went extinct at the end of the Eocene, 34 million years ago. Titanotheres have been described under various genera (Brontotherium, Titanotherium, BrontopsMegacerops was the first and therefore technically correct one.