Thecocoelurus

Thecocoelurus is a genus of theropod dinosaur from the early Cretaceous period of England. Its type specimen was discovered in strata from the Wessex Formation on the Isle of Wight by the Reverend William Fox, and after his death, it, alongside the rest of his collection, became the property of the British Museum of Natural History. The specimen was named in 1888 by Harry Govier Seeley, who assigned it to the genus Thecospondylus . In 1901, it was reassigned by Baron Franz Nopcsa to Coelurus. In 1923, the specimen was removed from either genus by Friedrich von Huene, who assigned it to a genus of its own. Thecocoelurus currently consists of one species, T. daviesi. The validity of the genus has been questioned, with a 2001 publication finding it to be a nomen dubium, although this treatment has not been maintained.

The phylogenetic placement of Thecocoelurus is uncertain. Originally it was believed to be a member of Coeluridae. Subsequently it has been suggested to be an ornithomimid, a more basal ornithomimosaur, an oviraptorosaur similar to caenagnathids, or a European representative of the therizinosaur lineage. In 2011 Darren Naish noted that many of the traits used to unite Thecocoelurus with oviraptosaurs were also found in a more basal theropod group, Noasauridae. Ergo, he suggested that it might have been some kind of ceratosaur.