Gobiatherium mirificum

Overview

Gobiatherium mirificum was an unusual mammal from Eocene Asia. Its long, low skull and widely flaring cheekbones stand out. Think of its horned Uintatherium relatives, then compare this animal's different face.^[1][2]

Key facts

Its skull lacks the cranial horns familiar in closely related groups. Instead, broad cheek regions and arching nasal bones give it a distinctive appearance. Head shape can vary this much even within the same broad family tree.^[1][2]

Time and place

It is known from Eocene Asia, with important material dating to the Middle Eocene. Think of a time around 40–50 million years ago. Fossils from the Irdin Manha and Arshanto formations in the Erlian Basin of present-day Inner Mongolia, China, have been studied.^[2][3]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The skull is long and low, with cheekbones that flare outward. The lower jaw is also long and relatively shallow. Metacarpals studied separately have been described as longer and more slender than those of Uintatherium. This animal allows differences in the head and limbs to be considered together.^[1][2]

Habitat and reproduction

The molars used to process food and the limbs that supported the body offer clues to life on land. Cusps and transverse ridges remain on the lower molars. Researchers compare them with the jaws of other ancient mammals to investigate food processing and relationships.^[1][3]

Fossil discovery

Osborn and Granger introduced material collected during a 1930 expedition as a new genus and species in 1932. The type skull is AM26624. New lower jaws from the Erlian Basin were studied later, adding material for comparison with the first known skull.^[1][3]

References

1. Osborn, H. F. & Granger, W. (1932), Coryphodonts and uintatheres from the Mongolian expedition of 1930. American Museum Novitates 552:1–16.
2. Schoch & Lucas1985 — The phylogeny and classification of the Dinocerata
3. 2006 IVPP — Dinocerate jaws from the Erlian Basin
4. Schoch & Lucas1985 — The phylogeny and classification of the Dinocerata
5. 2006 IVPP — Dinocerate jaws from the Erlian Basin
6. Osborn, H. F. & Granger, W. (1932), Coryphodonts and uintatheres from the Mongolian expedition of 1930. American Museum Novitates 552:1–16.
7. Bai et al.2018 — Age and distribution of mammals in the Erlian Basin
8. Granger1938 — A giant oxyaenid from the Upper Eocene of Mongolia

Research questions

Although the skull is very different, the teeth resemble those of other Uintatherium relatives. Which features best reveal relationships on the family tree? This example shows why cranial ornamentation, teeth and limbs are compared together.^[2]

Observation

Examine the widely flaring cheekbones and the low profile of the skull.^[1]