POCATELLO — Bones found in Bonneville County by an Idaho State University professor belonged to a relative of the Tyrannosaurus Rex.
L.J. Krumenacker, an adjunct professor of geosciences at ISU, found a femur bone he says is the oldest Cretaceous-age tyrannosaur bone found in North America, according to a news release from the university.
“This fossil shows that a variety of tyrannosaurs were present in western North America around 100 million years ago and well before these types of animals became the dominant predators near the end of the age of dinosaurs,” Krumenacker says in the release.
Krumenacker, who is also an affiliate curator at the Idaho Museum of Natural History, published an article in the Journal of Paleontology regarding the discovery.
The discovery was made in the Caribou Mountains.
“Southeastern Idaho has a lot of potential for further discoveries of ancient life from the age of dinosaurs and other times in history,” Krumenacker says in the release. “We have found lots of fossil fragments that show there is a great diversity of ancient dinosaurs and other animals from Idaho left to discover and learn more about.”
Based on the size of the partial femur bone discovered by Krumenacker, the animal is estimated to have weighed around 100 pounds. It is believed to be related to a similar tyrannosaur whose remains were found in Utah.
A partial femur bone from a Tyrannosaurus-like dinosaur and an approximation of how large the dinosaur would have been. | Courtesy Idaho State University
The fossil is currently in North Carolina being studied. But its permanent home will be at the Idaho Museum of Natural History in Pocatello. It will be featured in a 2023 exhibit, “Idaho Dinosaurs.”
The museum is commissioning a reconstruction of the dinosaur for the exhibit, according to the release.
“This new tyrannosaur is a reminder that scientific discovery is ongoing,” museum curator Brandon Peecook said in the release. “We’re excited to showcase the new specimen to the public not only as a cool fossil but also as a source of data for future science into the history of life.”