Coelurus

What it was like

Coelurus was a small, lightly built meat eater about 1.8 meters (6 feet) long, with long legs and a long tail. Its name comes from its hollow tail bones, which kept its body light.

Its world

It lived in the Late Jurassic in what is now Wyoming, in the United States, with other fossils reported from Utah and Colorado. Its bones come from the Morrison Formation, where it lived in the shadow of giants such as Diplodocus and Brontosaurus, and of the big hunters Allosaurus and Ceratosaurus.

How it was found

Marsh named Coelurus in 1879. For a long time it was mixed up with Ornitholestes, another small Morrison hunter, and several species were named and later dropped. Today it is seen as an early coelurosaur, part of the group that includes tyrannosaurs and birds.