The name is derived from the GreekΚιμωλίαkimolia, meaning "white chalk", and σαύροςsauros, meaning "lizard", in reference to the fact that the deposits in which it was found bear a superficial resemblance to the chalk deposits of the Western Interior Seaway.
In his catalogue of plesiosaur and ichthyosaur specimens preserved in the NHM, the British zoologist Richard Lydekker referred several Jurassic and Cretaceous plesiosaur species to Cimoliasaurus, including the new species C. richardsoni (now considered a species of Cryptoclidus) and C. cantabrigiensis, as well as Colymbosaurus and a number of previously described species from the Cambridge Greensand and Chalk Group.[4]
Nowadays, Cimoliasaurus is now recognized as being a derived elasmosaurid, effectively making the family name Cimoliasauridae Delair, 1959 a junior synonym of Elasmosauridae.[5]
Misassigned nominal species
Cimoliasaurus laramiensis Knight, 1900, now Tatenectes
^Lydekker., R., 1889, Catalogue of the fossil Reptilia and Amphibia in the British Museum (Natural History). Part II. Containing the orders Ichthyopterygia and Sauropterygia: London, Printed by Order of the Trustees of the British Museum, p. 307pp.
^F. Robin O'Keefe and Hallie P. Street (2009). "Osteology Of The Cryptoclidoid Plesiosaur Tatenectes laramiensis, With Comments On The Taxonomic Status Of The Cimoliasauridae". Journal of Vertebrate Paleontology 29 (1): 48–57.
^Fritsch, A. (1906). Über neue Saurierfunde in der Kreideformation Böhmens. Sitzungsberichte der Königlich Böhmischen Gesellschaft der Wissenschaften, Classe Mathematisch-Naturwissenschaftliche, 1906(33): 1–6.