Kileskus

Nobody knows for sure, but it was small. Its upper jaw bone was just under 30 cm long, while the same bone in adult Tyrannosaurus rex was 60 cm long or longer, so Kileskus was much smaller than its later relatives.4

Kileskus lived about 166 million years ago, during the Middle Jurassic period. That is about 100 million years before Tyrannosaurus rex appeared.14

Kileskus was a meat-eater. It was a theropod dinosaur, and its teeth and jaws show it hunted or scavenged other animals.1

Scientists do not know for sure, but it was an early tyrannosauroid, and many early tyrannosaurs were small and fuzzy. No feather fossils of Kileskus have been found, but it might have had some.4

Yes, Kileskus was a dinosaur. It was a theropod, a group of two-legged, mostly meat-eating dinosaurs that includes Tyrannosaurus rex.1

Kileskus is one of the oldest known tyrannosauroids, the group that includes T. rex. It helps scientists understand how tyrannosaurs first evolved, because it lived 100 million years before T. rex.1