Raptorex ('King of the Raptors') was a small tyrannosaur discovered in China, and named recently - in 2009. Raptorex was small, at about 2.5 to 3 metres long, but is one of the earliest known tyrannosaurs, dating back about 125 million years.
Raptorex has the same characteristics of later tyrannosaurs, including a comparatively large and solidly-built skull, long legs for running, and short, two fingered forelimbs. This is in contrast to the other early tyrannosaurs, such as Guanlong and Dilong, which had three-fingered hands, and smaller heads compared to their body size. This suggests that Raptorex is an advanced tyrannosaur for the time.