List of plesiosaur genera

This list of plesiosaurs is a comprehensive listing of all genera that have ever been included in the order Plesiosauria, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful (nomen dubium), or were not formally published (nomen nudum), as well as junior synonyms of more established names, and genera that are no longer considered plesiosaurs. The list currently includes 208 genera.

Scope and terminology

There is no official, canonical list of plesiosaur genera but one of the most thorough attempts can be found on the Plesiosauria section of Mikko Haaramo's Phylogeny Archive; also pertinent is the Plesiosaur Genera section at Adam Stuart Smith's Plesiosaur Directory.

Naming conventions and terminology follow the International Code of Zoological Nomenclature. Technical terms used include:

• Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the type specimens are later assigned to the same genus, the first to be published (in chronological order) is the senior synonym, and all other instances are junior synonyms. Senior synonyms are generally used, except by special decision of the ICZN, but junior synonyms cannot be used again, even if deprecated. Junior synonymy is often subjective, unless the genera described were both based on the same type specimen.
• Nomen nudum (Latin for "naked name"): A name that has appeared in print but has not yet been formally published by the standards of the ICZN. Nomina nuda (the plural form) are invalid, and are therefore not italicized as a proper generic name would be. If the name is later formally published, that name is no longer a nomen nudum and will be italicized on this list. Often, the formally published name will differ from any nomina nuda that describe the same specimen. In this case, these nomina nuda will be deleted from this list in favor of the published name.
• Preoccupied name: A name that is formally published, but which has already been used for another taxon. This second use is invalid (as are all subsequent uses) and the name must be replaced. As preoccupied names are not valid generic names, they will also go unitalicized on this list.
• Nomen dubium (Latin for "dubious name"): A name describing a fossil with no unique diagnostic features. As this can be an extremely subjective and controversial designation, this term is not used on this list.

The list

Genus Authors Year Status Age Location Notes Abyssosaurus Berezin 2011 Valid eK Europe Acostasaurus Gómez-Pérez Noè 2017 Valid eK South America Albertonectes Kubo Mitchell Henderson 2012 Valid lK North America Alexandronectes Otero et al. 2016 Valid lK Australasia Alexeyisaurus Sennikov Arkhangelsky 2010 Valid lT Europe "Alzadasaurus" Welles 1943 Anguanax Cau Fanti 2015 Valid lJ Europe Anningasaura Vincent Benson 2012 Valid eJ Europe Apatomerus Williston 1903 Valid eK Aphrosaurus Welles 1943 Valid lK "Apractocleidus" Smellie 1916 Jr. synonym Junior synonym of Cryptoclidus. Aptychodon Reuss 1855 Valid lK Archaeonectrus Owen 1865 Valid eJ Europe Arminisaurus Sachs Kear 2018 Valid eJ Europe Aristonectes Cabrera 1941 Valid lK South America, Antarctica Attenborosaurus Bakker 1993 Valid eJ Europe Atychodracon Smith 2015 Valid Europe Avalonnectes Benson Evans Druckenmiller 2012 Valid eJ Europe Bathyspondylus Delair 1982 Valid lJ Bishanopliosaurus Dong 1980 Valid eJ Bobosaurus Dalla Vecchia 2006 Valid lT Borealonectes Sato Wu 1980 Valid mJ Brachauchenius Williston 1903 Valid eK to lK Brancasaurus Wegner 1914 Valid eK Brimosaurus Leidy 1855 Valid lK Callawayasaurus Carpenter 1999 Valid eK Cardiocorax Araújo et al. 2015 Valid lK Africa Ceraunosaurus Thurmond 1968 Jr. synonym Junior synonym of Trinacromerum. Chubutinectes O'Gorman et al. 2023 Valid lK South America Cimoliasaurus Leidy 1851 Valid lK Colymbosaurus Seeley 1874 Valid lJ Crymocetus Cope 1869 Valid eK Cryonectes Vincent Bardet Mattioli 2013 Valid eJ Europe Cryptoclidus Seeley 1892 Valid mJ Europe Discosaurus Leidy 1851 Valid Djupedalia Knutsen Druckenmiller Hurum 2012 Valid lJ Europe Dolichorhynchops Williston 1903 Valid North America Dravidosaurus Yadagiri Ayyasami 1979 Nomen dubium lK Asia Possibly a stegosaurian dinosaur Eardasaurus Ketchum Benson 2022 Valid mJ Europe Edgarosaurus Druckenmiller 2002 Valid eK North America Eiectus Noè Gómez-Pérez 2021 Valid eK Australia Elasmosaurus Cope 1868 Valid North America Asia Embaphias Cope 1894 Nomen dubium lK North America Eoplesiosaurus Benson Evans Druckenmiller 2012 Valid eJ Europe Eopolycotylus Albright Gillette Titus 2007 Valid Eretmosaurus Seeley 1874 Valid Eromangasaurus Kear 2005 Valid Eurycleidus Andrews 1922 Valid Eurysaurus Gaudry 1878 Valid Fluvionectes Campbell et al. 2021 Valid lK North America Franconiasaurus Sachs Eggmaier Madzia 2024 Valid eJ Europe Fresnosaurus Welles 1943 Valid Futabasaurus Sato Hasegawa Manabe 2006 Valid lK Asia Also a theropod nomen nudum ("Futabasaurus"). Gallardosaurus Gasparini 2009 Valid "Georgia" Otschev 1976 Preoccupied Preoccupied by a genus of mollusk, renamed Georgiasaurus. Georgiasaurus Otschev 1978 Valid Goniosaurus Meyer 1860 Valid Gronausaurus Hampe 2013 Valid eK Europe Hastanectes Benson et al. 2012 Valid eK Europe Hauffiosaurus O'Keefe 2001 Valid Hydralmosaurus Welles 1943 Valid Hydrorion Grobmann 2006 Valid Hydrotherosaurus Welles 1943 Valid lK North America Ischyrodon von Meyer 1838 Jr. synonym Junior synonym of Liopleurodon. Jucha Fischer et al. 2020 Valid eK Europe Kaiwhekea Cruickshank Fordyce 2002 Valid lJ Europe Kawanectes O'Gorman 2016 Valid lK South America Kimmerosaurus Brown 1981 Valid Kronosaurus Longman 1924 Valid Australia, South America Lagenanectes Sachs Hornung Kear 2017 Valid eK Europe Leivanectes Páramo-Fonseca O'Gorman Gasparini Padilla Parra Ruge 2019 Valid eK South America Leptocleidus Andrews 1922 Valid eK Europe, Africa, Australia Leurospondylus Brown 1913 Valid Libonectes Carpenter 1997 Valid Lindwurmia Vincent Storrs 2019 Valid eJ Europe Liopleurodon Sauvage 1873 Valid Lorrainosaurus Sachs et al. 2023 Valid mJ Europe Originally assigned to Simolestes. Luetkesaurus Kiprijanoff 1883 Valid Luskhan Fischer et al. 2017 Valid eK Europe Lusonectes Smith Araújo Mateus 2011 Valid eJ Europe Macroplata Swinton 1930 Valid eJ Europe Makhaira Fischer et al. 2015 Valid eK Manemergus Buchy Metayer Frey 2005 Valid Marambionectes O'Gorman et al. 2024 Valid lK Antarctica Maresaurus Gasparini 1997 Valid Marmornectes Ketchum Benson 2011 Valid mJ Europe Martinectes Clark O’Keefe Slack 2024 Valid lK North America Mauisaurus Hector 1874 Valid Mauriciosaurus Frey et al. 2017 Valid lK North America Megacephalosaurus Schumacher Carpenter Everhart 2013 Valid lK North America Megalneusaurus Knight 1898 Valid Meyerasaurus Smith Vincent 2010 Valid eJ Europe Microcleidus Watson 1911 Valid eJ Monquirasaurus Noè Gómez-Pérez 2021 Valid eK South America Morenosaurus Welles 1943 Valid Morturneria Chatterjee Creisler 1994 Jr. synonym Junior synonym of Aristonectes. Muraenosaurus Seeley 1874 Valid mJ Europe Nakonanectes Serratos Druckenmiller Benson 2017 Valid lK North America Nichollssaura Druckenmiller Russell 2009 Valid eK North America "Nichollsia" Druckenmiller Russell 2008 Preoccupied Preoccupied by a genus of isopod, renamed Nichollssaura. Occitanosaurus Bardet Fernandez Garcia-Ramos Superbiola Pinuela Ruiz-Omenaca Vincent 2008 Valid Ogmodirus Williston Moodie 1917 Valid Oligosimus Leidy 1872 Nomen dubium lK North America Opallionectes Kear 2006 Valid Ophthalmothule Roberts et al. 2020 Valid lJ-eK Europe Orophosaurus Cope 1851 Valid Pachycostasaurus Cruickshank Martill 1996 Valid Pahasapasaurus Schumacher 2007 Valid "Palmula" Albright Gillette Titus 2007 Preoccupied Preoccupied by a genus of foraminifer, renamed Palmulasaurus. Palmulasaurus Albright Gillete Titus 2007 Valid Pantosaurus Marsh 1893 Valid Peloneustes Lydekker 1889 Valid mJ Europe Peyerus Stromer 1935 Jr. synonym Junior synonym of Leptocleidus. Picrocleidus Andrews 1909 Jr. synonym Junior synonym of Muraenosaurus. Piptomerus Cope 1887 Valid Piratosaurus Leidy 1865 Valid Plesioelasmosaurus Schumacher Everhart 2022 Valid lK North America Plesiopharos Puértolas-Pascual et al. 2021 Valid eJ Europe Plesiopleurodon Carpenter 1996 Valid Plesiopterys O'Keefe 2004 Valid Plesiosaurus Conybeare 1821 Valid eJ Europe Pliosaurus Owen 1841 Valid Polycotylus Cope 1869 Valid Polyptychodon Owen 1841 Valid Rhaeticosaurus Wintrich et al. 2017 Valid lT Europe Rhomaleosaurus Seeley 1871 Valid eJ Europe Sachicasaurus Páramo-Fonseca Benavides-Cabra Gutiérrez 2018 Valid eK South America Scalamagnus Clark O’Keefe Slack 2024 Valid lK North America Scanisaurus Persson 1959 Valid Seeleyosaurus White 1940 Valid eJ Europe Serpentisuchops Persons Street Kelley 2022 Valid lK North America Simolestes Andrews 1909 Valid Sinopliosaurus Young 1944 Valid eK Spitrasaurus Knutsen Druckenmiller Hurum 2012 Valid lJ Europe Spondylosaurus Fisher 1845 Jr. synonym Junior synonym of Pliosaurus. Stratesaurus Benson Evans Druckenmiller 2012 Valid eJ Europe Sulcusuchus Gasparini Spalletti 1992 Valid lK South America Stenorhynchosaurus Páramo et al. 2016 Valid eK South America Stereosaurus Seeley 1869 Valid Sthenarosaurus Watson 1911 Valid eJ "Stretosaurus" Tarlo 1959 InValid Type specimen is undiagnostic and should be assigned to Thalassophonea indeterminate. Strongylokrotaphus Novozhilov 1964 Jr. synonym Junior synonym of Pliosaurus. Styxosaurus Welles 1952 Valid lK North America Taphrosaurus Cope 1870 Valid lK "Tatenectes" Knight 1900 Valid Terminonatator Sato 2003 Valid lK Thalassiodracon Storrs Taylor 1996 Valid lT-eJ Europe Thalassiosaurus Welles 1953 Jr. synonym Junior synonym of Styxosaurus. Thalassomedon Welles 1943 Valid lK North America Thalassonomosaurus Welles 1943 Jr. synonym Junior synonym of Styxosaurus. Thaumatodracon Smith Araújo 2017 Valid lK Europe "Thaumatosaurus" Meyer 1841 InValid Holotype is not diagnostic and can be referred to Pliosauroidea indet at best. Thililua Bardet Suberbiola Jalil 2003 Valid lK "Tremamesacleis" White 1940 Jr. synonym Junior synonym of Muraenosaurus. Trematospondylus Quenstedt 1858 Nomen dubium mJ Europe Tricleidus Andrews 1909 Valid Trinacromerum Cragin 1888 Valid lK North America Tuarangisaurus Wiffen Moisley 1986 Valid lK "Turneria" Chatterjee Small 1989 Preoccupied Preoccupied by a genus of ant, renamed Morturneria which is now recognised as a junior synonym of Aristonectes. Umoonasaurus Kear Schroeder Lee 2006 Valid eK Australia Unktaheela Clark O’Keefe Slack 2024 Valid lK North America Uronautes Cope 1870 Valid lK Vectocleidus Benson et al. 2012 Valid eK Europe Vegasaurus O'Gorman Salgado Olivero Marenssi 2015 Valid lK Antarctica Vinialesaurus Gasparini Bardet Vinent Iturralde 2002 Valid lJ Westphaliasaurus Schwermann Sander 2011 Valid eJ Europe Woolungasaurus Persson 1960 Valid eK Wunyelfia Otero Soto-Acuña 2020 Valid lK South America Yuzhoupliosaurus Zhang 1985 Valid mJ "Zahrisaurus" Malkani 2019 Dubious lK Asia Zarafasaura Vincent Pereda-Suberbiola Bouya Amaghzaz Meslouh 2011 Valid lK Africa		Aristonectes Attenborosaurus Atychodracon Cryptoclidus Dolichorhynchops Edgarosaurus Elasmosaurus Franconiasaurus Futabasaurus Hydrotherosaurus Kaiwhekea Kronosaurus Leptocleidus Liopleurodon Macroplata Martinectes Microcleidus Muraenosaurus Nichollssaura Peloneustes Plesiopleurodon Plesiosaurus Pliosaurus Polyptychodon Rhomaleosaurus Scalamagnus Seeleyosaurus Simolestes Styxosaurus Thalassiodracon Thalassomedon Trinacromerum Umoonasaurus

See also

• Sauropterygia
  • Plesiosaur
• List of dinosaurs
• List of ichthyosaurs
• List of mosasaurs
• List of pterosaurs

References

• Haaramo, Mikko (15 November 2005). "Plesiosauria". Mikko's Phylogeny Archive. Archived from the original on 2 September 2006. Retrieved 4 November 2023.
• Smith, Adam Stuart. "Plesiosaur Genera". The Plesiosaur Directory. Archived from the original on 21 March 2006. Retrieved 4 November 2023.