Guanlong

What it was like

Guanlong was an early relative of the tyrannosaurs, much smaller and lighter than its famous descendants. It grew to about 3 meters (10 feet) long, and a thin, blade-like crest ran along the top of its snout, probably used for display rather than fighting.

Its arms were longer and its build lighter than those of later tyrannosauroids, showing how different this early branch of the family looked before larger, heavier-bodied hunters evolved.

Its world

Guanlong lived from about 162 to 155 million years ago, in the Late Jurassic, in what is now China. Its fossils come from the Shishugou Formation.

It shared its world with the long-necked Mamenchisaurus, the predator Sinraptor, and Monolophosaurus, another crested meat eater from the same region.

How it was found

Xu and colleagues named Guanlong in 2006. Only one fossil find has been reported for the genus, made up of an adult and a nearly complete juvenile skeleton found together. Guanlong is one of the earliest known tyrannosauroids, and its closest relatives include Proceratosaurus and Yutyrannus, part of the crested family Proceratosauridae.