Calamosaurus

Calamosaurus (meaning "reed lizard") is a genus of small theropod dinosaur, from the Early Cretaceous of the Isle of Wight, England. It is based on two cervical vertebrae (NHMUK PV R 901), collected by Reverend William Fox. These fossils come from sedimentary rocks of the Wessex Formation and are Barremian in age. The type species of Calamosaurus, named Calamospondylus foxi by Richard Lydekker, was named in honour of Fox. Calamospondylus, however, was a preoccupied name, forcing Lydekker to change the genus name to Calamosaurus. This has subsequently led to immense confusion, with some authors believing the two genera to be synonymous. The systematic position of Calamosaurus within theropods has been controversial, and placements within Compsognathidae and Ornithomimosauria have been suggested. More recently, researchers have suggested affinities with the Tyrannosauroidea and Alvarezsauroidea.

==Discovery and naming== The type specimen, NHMUK PV R 901, consisting of two articulated cervical (neck) vertebrae, was part of the "Fox collection", a collection of fossils collected by the Rev. William Fox which were given to the Natural History Museum in London on his death. When cataloguing the Fox collection, Richard Lydekker came across these bones and named them Calamospondylus foxi. The name derives from the Ancient Greek kalamos ('reed', 'reed pen') and spondylus ('vertebra') and hints at the slender and lightweight build of the vertebrae. Unbeknownst to Lydekker, the name Calamospondylus had already been coined in 1866 (by Reverend Fox himself, the very man honored in Lydekker's species name). Upon realising his mistake, Lydekker promptly renamed it, creating the new combination Calamosaurus foxi (from the Latin sauros, "lizard") in 1891.