Xiongguanlong

Xiongguanlong is a genus of tyrannosauroid dinosaur that lived in the Early Cretaceous of what is now China. The type species is X. baimoensis, described in 2009 by a group of researchers from China and the United States. The genus name refers to the city of Jiayuguan, a city in northwestern China. The specific name is derived from bai mo, "white ghost", after the "white ghost castle", a rock formation near the fossil site. The fossil is believed to be from the Aptian to Albian stages (between 100 to 125 million years ago).[1]

Xiongguanlong split off from the main branch of the Tyrannosauroidea just below Appalachiosaurus, being the sister taxon of a clade consisting of Appalachiosaurus and the Tyrannosauridae. It was intermediate in size between earlier tyrannosauroids from the Barremian and later tyrannosaurids from the Late Cretaceous, such as Tyrannosaurus, and had a long muzzle resembling that of Alioramus.[1]