Guanlong was a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of proceratosaurid tyrannosauroid dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

, one of the earliest known examples of the lineage.
About 3.0 metres (9.8 ft) long, its fossils were found in the Shishugou Formation

Shishugou Formation

The Shishugou Formation is a geological formation in Xinjiang, China, whose strata date back to the Late Jurassic period. Dinosaur remains are among the fossils that have been recovered from the formation....

 dating to about 160 million years ago, in the Oxfordian stage

Oxfordian stage

The Oxfordian is, in the ICS' geologic timescale, the earliest age of the Late Jurassic epoch, or the lowest stage of the Upper Jurassic series. It spans the time between 161.2 ± 4 Ma and 155.7 ± 4 Ma...

 of the Late Jurassic

Late Jurassic

The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 161.2 ± 4.0 to 145.5 ± 4.0 million years ago , which is preserved in Upper Jurassic strata. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age...

 period, 92 million years before its well-known relative Tyrannosaurus

Tyrannosaurus

Tyrannosaurus meaning "tyrant," and sauros meaning "lizard") is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex , commonly abbreviated to T. rex, is a fixture in popular culture. It lived throughout what is now western North America, with a much wider range than other...

. This bipedal saurischia

Saurischia

Saurischia meaning 'lizard' and ischion meaning 'hip joint') is one of the two orders, or basic divisions, of dinosaurs. In 1888, Harry Seeley classified dinosaurs into two orders, based on their hip structure...

n theropod shared many traits with its descendants, and also had some unusual ones, like a large crest on its head.