{{Short description|Extinct genus of reptiles}} {{Automatic taxobox | fossil_range = Late Cretaceous, {{fossilrange|Maastrichtian}} | image = Cimoliasaurus.jpg | image_caption = ''Cimoliasaurus magnus'' vertebrae | taxon = Cimoliasaurus | authority = Leidy, 1851 | type_species = {{extinct}}'''''Cimoliasaurus magnus''''' | type_species_authority = Leidy, 1851 }}
'''''Cimoliasaurus''''' was a plesiosaur that lived during the Late Cretaceous (Maastrichtian) of the eastern United States, with fossils known from New Jersey, North Carolina, and Maryland.
==Etymology== The name is derived from the Greek {{lang|grc|Κιμωλία}} {{lang|grc-Latn|kimolia}}, meaning "white chalk", and {{lang|grc|σαύρος}} {{lang|grc-Latn|sauros}}, 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.
==Taxonomic history== thumb|upright|left|A: ''Cimoliasaurus australis'' The name ''Cimoliasaurus magnus'' was coined by Joseph Leidy for '''ANSP 9235''', one anterior and 12 posterior cervical vertebrae collected in Maastrichtian-aged greensand deposits of the New Egypt and Navesink Formations in Burlington County, New Jersey.<ref>Leidy, J. 1851. [Descriptions of a number of fossil reptilian and mammalian remains]. Proc. Acad. Nat. Sci. Phila. 5:325-327.</ref> A specimen is also known from coeval limestone deposits of the Peedee Formation in Pender County, North Carolina.<ref>{{Cite journal |last=Parris |first=David C. |last2=Grandstaff |first2=Barbara Smith |date=2004 |title=A Pterosaur Femur From The Upper Cretaceous of North Carolina |url=https://core.ac.uk/download/pdf/345087521.pdf#page=55 |journal=Southeastern Geology |volume=43 |issue=1 |pages=51-55}}</ref> There is also a tentative record from the Maastrichtian-aged Severn Formation in Maryland when in 1988, Colin McEwen discovered a vertebra of a Cimoliasaurus during a school field trip. The discovery is recorded in the National Geographic November 1988 issue.<ref>{{Cite web |title=PBDB Taxon |url=https://paleobiodb.org/classic/basicTaxonInfo?taxon_no=65125 |access-date=2024-09-24 |website=paleobiodb.org}}</ref>
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.<ref>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.</ref>
Nowadays, ''Cimoliasaurus'' is now recognized as being a derived elasmosaurid, effectively making the family name Cimoliasauridae <small>Delair, 1959</small> a junior synonym of Elasmosauridae.<ref>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.</ref>
===Misassigned nominal species===
* ''Cimoliasaurus laramiensis'' Knight, 1900, now ''Tatenectes'' * ''Cimoliasaurus richardsoni'' Lydekker, 1889, now ''Cryptoclidus richardsoni'' * ''Cimoliasaurus valdensis'' Lydekker, 1889, now ''Hastanectes'' * ''Cimoliasaurus teplicensis'' Fritsch, 1906 (nomen dubium)<ref>[http://www.osel.cz/11084-skutecna-ceska-lochneska.html Czech article about ''C. teplicensis'' with English summary on ''Osel.cz'']</ref><ref>Fritsch, A. (1906). Über neue Saurierfunde in der Kreideformation Böhmens. ''Sitzungsberichte der Königlich Böhmischen Gesellschaft der Wissenschaften, Classe Mathematisch-Naturwissenschaftliche'', '''1906(33)''': 1–6.</ref>
==See also== * List of plesiosaur genera * Timeline of plesiosaur research
== References == {{Reflist}}
==External links== * https://web.archive.org/web/20080414142638/http://www.palaeos.com/Vertebrates/Units/220Lepidosauromorpha/220.820.html#Cimoliasaurus
{{Plesiosauria|Plesiosauroidea}} {{Taxonbar|from=Q5120155}}
Category:Late Cretaceous plesiosaurs of North America Category:Elasmosauridae Category:Fossil taxa described in 1851 Category:Taxa named by Joseph Leidy Category:Fossils of the United States Category:Sauropterygian genera