Fossil range: Early Cretaceous, 125-100 million years ago
Li et al., 2009
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).
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.