Calamosaurus
| Calamosaurus Temporal range: Barremian,  | |
|---|---|
| Cervical vertebra of Calamosaurus foxi | |
| Scientific classification | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Clade: | Dinosauria | 
| Clade: | Saurischia | 
| Clade: | Theropoda | 
| Family: | †Compsognathidae | 
| Genus: | †Calamosaurus Lydekker, 1891 | 
| Species: | †C. foxi | 
| Binomial name | |
| †Calamosaurus foxi (Lydekker, 1889 [originally Calamospondylus]) | |
| Synonyms | |
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Calamosaurus (meaning "reed lizard") was a genus of small theropod dinosaur from the Barremian-age Lower Cretaceous Wessex Formation of the Isle of Wight, England. It is based on two cervical vertebrae (NHMUK PV R 901), collected by Reverend William Fox.