Unprepared Oreodont (Leptauchenia) Skull - South Dakota

This is an unprepped skull of Leptauchenia decora, an Oreodont, from the the White River Formation of Pennington County, South Dakota. The rock was split nicely along the right side of the skull, exposing the jaw and teeth. This rock is accompanied with the specimen since some of the jaw is still attached to the negative split.

The skull hasn't undergone any restoration and has been left as it was found within the rock. It would be perfect for someone interested in fossil preparation. With the large section of rock attached to the skull, there's no telling what else you may find within the rock during prep. The rock measures 7.1 x 4.8 x 4.3" and the skull within is at least 4.5" long.

Because the eyes and nostrils were placed high on the head, it was long assumed that Leptauchenia was an aquatic or semi-aquatic animal. However, because their fossils have never been found in floodplain deposits or river channels but are found abundantly abundance in fossil sand dunes, paleontologist Donald Prothero suggests that they were desert-dwelling animals. According to Prothero's interpretation, the high-placed eyes and nostrils served to filter out sand while burrowing, or while digging themselves free of sand dunes.