Coniasaurus is an extinct genus of Late Cretaceous marine squamates that range in age from Cenomanian to Santonian. It was first described by Richard Owen in 1850 from lower Cenomanian chalk deposits in southeast England (Sussex). Two species have been described from this genus: C. crassidens (Owen, 1850), known from Cenomanian to Santonian deposits from southeast England, Germany and North America, and C. gracilodens (Caldwell, 1999) from the Cenomanian of southeast England.
Temporal range: Late Cretaceous,
|C. crassidens holotype, drawn by James Erxleben in 1850|
Coniasaurus has only been described from incomplete specimens, but it is known to have had a relatively elongate skull with specialised teeth. By comparison with Dolichosaurus, it may have had four short limbs and an elongate neck and body. A maximum length of about 0.5 m has been proposed.
- Shimada K. & Bell G.L.Jr (2006). "Coniasaurus Owen, 1850 (Reptilia: Squamata), from the Upper Cretaceous Niobrara Chalk of western Kansas". Journal of Paleontology. 80 (3): 589–593. doi:10.1666/0022-3360(2006)80[589:corsft]2.0.co;2.[permanent dead link]
- Owen, R. (1850). Descriptions of the fossils of the Chalk Formation. Description of the fossil reptiles of the Chalk Formation. The Geology and Fossils of the Tertiary and Cretaceous Formations of Sussex 378-404
- Caldwell M.W. & Cooper J.A. (1999). "Redescription, palaeobiogeography and palaeoecology of Coniasaurus crassidens Owen, 1850 (Squamata) from the Lower Chalk (Cretaceous; Cenomanian) of SE England" (PDF). Zoological Journal of the Linnean Society. 127 (4): 423–452. doi:10.1111/j.1096-3642.1999.tb01380.x.
- Caldwell M.A. (1999). "Squamate phylogeny and the relationships of snakes and mosasauroids" (PDF). Zoological Journal of the Linnean Society. 125 (1): 115–147. doi:10.1111/j.1096-3642.1999.tb00587.x.