2.15" Fossil Tyrannosaur (T. rex) Rib Section - Wyoming

How Do We Know It Is T. Rex?

This bone fragment comes from a partial Tyrannosaurus rex skeleton discovered on a ranch near Newcastle, Wyoming. Sadly, most of the specimen had been lost to decades of erosion and surface exposure, leaving behind only scattered fragments and a few teeth. The surviving fragments were carefully collected, offering a rare opportunity to own an authentic piece of the most legendary dinosaur in history at an accessible price.

Intriguingly, some fragments show patches of yellow fluorescence under shortwave ultraviolet light. This unusual glow is currently being studied, as researchers suspect it may reflect something intrinsic to the animal rather than simply a byproduct of fossilization.

About The Lance Formation

The Lance Formation of eastern Wyoming is a Late Cretaceous (69–66 million years old) unit that represents the same geologic age as the famous Hell Creek Formation of Montana and the Dakotas. Although they are time-equivalent, the Lance and Hell Creek preserve subtly different environments. Hell Creek reflects a humid, forested coastal plain punctuated by volcanic ash deposits, while the Lance records a slightly drier, more open floodplain landscape with broader river systems and fewer ash layers. Together, they provide a complementary view of life in the final chapter of the dinosaur era.

Perhaps the most famous Lance resident would be Tyrannosaurus rex, the largest North American carnivore to ever live. However, other smaller theropods also roamed the American midwest in this subtropical coastal stream system, including the beaked Ornithomimus, a lanky running theropod with a build similar to a modern ostrich, as well as several small predatory troodonts such as Paronychodon and Pectinodon.

Herbivorous dinosaurs also took advantage of the abundance offered by this unique era. Armored ankylosaurs dwelt in herds, their safety assured by their numbers, their heavy bone plating protecting most of their bodies and even their eyelids, and huge bone clubs on the ends of their tails providing them with powerful offensive capabilities. Ceratopsians like the famous Triceratops also formed protective herds, guarding their necks with frills and horns. Their smaller relatives, the dome-headed pachycephalosaurs, were also well represented in the area. Hadrosaurs, duck-billed titans with huge batteries of plant-grinding teeth in elongated snouts, are also well known from the region.

In addition to dinosaurs, a wide variety of fishes, amphibians, lizards, snakes, turtles, champsosaurs, crocodilians, and pterosaurs have been found in the formation.