|Named By:||Othniel Charles Marsh in 1879|
|Time Period:||Late Jurassic, 153-150 Ma|
|Location:||USA, Wyoming - Morrison Formation|
|Size:||Estimated to be about 2.4 meters long|
|Fossil(s):||Partial post cranial skeleton|
|Classification:||| Chordata | Reptilia | Dinosauria | Saurischia | Theropoda | Coelurosauria | Coeluridae ||
|Also known as:||| Coelurus agilis | Elaphrosaurus agilis ||
Coelurus ( si-LEWR-as) is a genus of coelurosaurian dinosaur from the Late Jurassic period (mid-late Kimmeridgian faunal stage, 153-150 million years ago). The name means "hollow tail", referring to its hollow tail vertebrae (Greek koilos, koilos = hollow + oura, oura = tail). Although its name is linked to one of the main divisions of theropods (Coelurosauria), it has historically been poorly understood, and sometimes confused with its better-known contemporary Ornitholestes. Like many dinosaurs studied in the early years of paleontology, it has had a confusing taxonomic history, with several species being named and later transferred to other genera or abandoned. Only one species is currently recognized as valid: the type species, C. fragilis, described by Othniel Charles Marsh in 1879. It is known from one partial skeleton found in the Morrison Formation of Wyoming, United States. It was a small bipedal carnivore with elongate legs.