Guanlong

Guanlong () is an extinct genus of proceratosaurid tyrannosauroid dinosaur from the Late Jurassic (Oxfordian) Shishugou Formation of China. It was first described in 2006 by Xu Xing and colleagues, who found it to represent a new taxon related to Tyrannosaurus. Two individuals are currently known, consisting of a partially complete adult and a nearly complete juvenile.

==Discovery== thumb|left|The paratype specimen IVPP V14532, with its skull removed Guanlong was discovered in the Dzungaria area of China by a joint expedition by scientists from the Institute of Vertebrate Paleontology and Paleoanthropology and George Washington University, and named by Xu Xing and others in 2006. Guanlong comes from the Chinese words for "crown" () and "dragon" (), referring to the crest. The specific epithet, wucaii (), means "multicoloured" and refers to the colours of rock of the Wucaiwan (), the multi-hued badlands where the creature was found. thumb|Adult material At present, Guanlong is known from two specimens, one discovered on top of the other, with three other individual theropod dinosaurs, in the Shishugou Formation. The holotype (IVPP V14531) is a reasonably complete, partially articulated adult skeleton, and was the one on top. Another, immature specimen, the paratype IVPP V14532, is known from fully articulated and nearly complete remains. It was presumed to have been trampled, after death, by the adult. The crest on the skull of the immature specimen is notably smaller and restricted to the forward portion of the snout, while the adult has a larger and more extensive crest. The crests of both specimens are thin, delicate structures that likely served as display organs, possibly for events like mating.