List of plesiosaur genera

Last updated

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 174 genera.

Contents

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; [1] also pertinent is the Plesiosaur Genera section at Adam Stuart Smith's Plesiosaur Directory. [2]

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

The list

GenusAuthorsYearStatusAgeLocationNotesImages
Abyssosaurus [3] Berezin 2011 Valid Early Cretaceous Flag of Russia.svg Russia Had a uniquely short, triangular skull with extremely large eye sockets Abyssosaurus nataliae.png
Acostasaurus [4] Gómez-Pérez & Noè 2017 Valid Early Cretaceous Flag of Colombia.svg Colombia Noted for its unusually caniniform dentition compared to other pliosaurids Acostasaurus pavachoquensis by duskyvel-dbys3fi.png
Albertonectes [5] Kubo et al. 2012 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada Had the longest neck of any known plesiosaur, made up of seventy-six vertebrae Albertonectes vanderveldei.png
Alexandronectes Otero et al. 2016 Valid Late Cretaceous Flag of New Zealand.svg New Zealand The first aristonectine from which a stapes is known [6] Alexandronectes zealandiensis.png
Alexeyisaurus Sennikov & Arkhangelsky 2010 Dubious Late Triassic Flag of Russia.svg Russia Although originally described as an elasmosaurid plesiosaur, it was suggested to be an undiagnostic sauropterygian taxon by subsequent analyses
Alzadasaurus Welles & Bump 1949 Jr. synonymN/AN/AJunior synonym of Styxosaurus
Anguanax [7] Cau & Fanti 2015 Valid Late Jurassic Flag of Italy.svg Italy Several features of its skull would indicate a diet of soft or small-bodied prey Anguanax skull.jpg
Anningasaura [8] Vincent & Benson 2012 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Known from a partial skeleton belonging to a juvenile animal Hydrorion brachypterygius skull.JPG
Apatomerus Williston 1903 Dubious? Early Cretaceous Flag of the United States.svg United States Originally identified as a crocodilian and later reinterpreted as a pterosaur, although it may very likely be a plesiosaur
Aphrosaurus Welles 1943 Valid Late Cretaceous Flag of the United States.svg United States Distinguished by the presence of a deepened ventral notch along the centra of its cervical vertebrae Aphrosaurus furlongi profile reconstruction.jpg
Apractocleidus Smellie 1915 Jr. synonymN/AN/AJunior synonym of Cryptoclidus
Aptychodon von Reuss 1855 Valid Late Cretaceous Flag of the Czech Republic.svg Czech Republic Some studies suggest this genus may be a potential junior synonym of Polyptychodon Aptychodon teeth 2.png
Archaeonectrus Novozhilov 1964 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Originally mistakenly believed to be a species of Plesiosaurus Archaeonectrus NT.jpg
Aristonectes Cabrera 1941 Valid Late Cretaceous Antarctica
Flag of Argentina.svg Argentina
Flag of Chile.svg Chile
This genus would have migrated regularly between Patagonia and Antarctica as implied by its fossil record Aristonectes parvidens.png
Arminisaurus Sachs & Kear 2017 Valid Early Jurassic Flag of Germany.svg Germany Shares some features of its skeleton with leptocleidian plesiosauroids Arminisaurus.jpg
Attenborosaurus Bakker 1993 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Named in honor of British broadcaster and naturalist David Attenborough Attenborosaurus conybeari life restoration.jpg
Atychodracon Smith 2015 Valid Late Triassic to Early Jurassic Flag of the United Kingdom.svg United Kingdom Has been assigned to four different genera before its formal description Atychodracon DB.jpg
Avalonnectes [9] Benson, Evans & Druckenmiller 2012 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom One of the oldest plesiosaurs known to date Holotype of Avalonnectes arturi NHMUK 14550.png
Bathyspondylus Delair 1982 Valid Late Jurassic Flag of the United Kingdom.svg United Kingdom Possesses an unusual mix of pliosauroid and plesiosauroid features Bathyspondylus.jpg
Bishanopliosaurus Dong 1980 Valid Early Jurassic to Middle Jurassic Flag of the People's Republic of China.svg China Could be distinguished by the bifurcated ribs of its sacrum Bishanopliosaurus.jpg
Borealonectes Sato & Wu 2008 Valid Middle Jurassic Flag of Canada (Pantone).svg Canada One of the few North American plesiosaurs that lived during the Jurassic
Boyacasaurus [10] Benavides-Cabra et al. 2025 Valid Early Cretaceous Flag of Colombia.svg Colombia Known from two specimens found in association with ammonites
Brachauchenius Williston 1903 Valid Late Cretaceous Flag of Morocco.svg Morocco
Flag of the United States.svg United States
Several pliosaurid specimens of same age had been referred to this genus, although they were either renamed as new taxa or considered dubious Brachauchenius lucasi2DB.jpg
Brancasaurus Wegner 1914 Valid Early Cretaceous Flag of Germany.svg Germany Its cervical vertebrae are noted for having shark fin-shaped neural spines Brancasaurus habitat.jpg
Brimosaurus Leidy 1854 Dubious Late Cretaceous Flag of the United States.svg United States May be synonymous with Cimoliasaurus
Callawayasaurus Carpenter 1999 Valid Early Cretaceous Flag of Colombia.svg Colombia Has no pectoral bars, a trait shared with Terminonatator Callawayasaurus colombiensis.png
Cardiocorax [11] Araújo et al. 2015 Valid Late Cretaceous Flag of Angola.svg Angola The morphology of its scapula suggests a relatively unique swimming style for this genus Cardiocorax mukulu.png
Ceraunosaurus Thurmond 1968 Jr. synonymN/AN/AJunior synonym of Trinacromerum
Chubutinectes [12] O'Gorman et al. 2023 Valid Late Cretaceous Flag of Argentina.svg Argentina Larger than the contemporary Kawanectes due to its marine habitat
Cimoliasaurus Leidy 1851 Valid Late Cretaceous Flag of the United States.svg United States Discovered in sediments that superficially resemble the chalk deposits found in the Western Interior Seaway Cimoliasaurus.jpg
Colymbosaurus Seeley 1874 Valid Middle Jurassic to Late Jurassic Flag of Norway.svg Norway
Flag of the United Kingdom.svg United Kingdom
The holotype humerus was originally misidentified as a femur Colymbosaurus megadeirus.png
Crymocetus Cope 1869 Dubious Late Cretaceous Flag of the United Kingdom.svg United Kingdom Today seen as an indeterminate plesiosaur. Only known from a single vertebra Crymocetus.jpg
Cryonectes [13] Vincent, Bardet & Mattioli 2012 Valid Early Jurassic Flag of France.svg France Possessed a relatively elongated snout Cryonectes neustriacus.jpg
Cryptoclidus Seeley 1892 Valid Middle Jurassic to Late Jurassic Flag of the United Kingdom.svg United Kingdom Would have preyed on small, soft-bodied animals as indicated by the delicate build of its skull and teeth Cryptoclidus NT small.jpg
Discosaurus Leidy 1851 Valid Late Cretaceous Flag of the United States.svg United States Has been argued to be the same taxon as Elasmosaurus Discosaurus.jpg
Djupedalia [14] Knutsen, Druckenmiller & Hurum 2012 Valid Late Jurassic Flag of Norway.svg Norway Named after former Minister of Education and Research Øystein Djupedal Djupedalia engeri.png
Dolichorhynchops Williston 1902 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada
Flag of the United States.svg United States
Described two years after its discovery Dolichorhynchops osborni.png
Dravidosaurus Yadagiri & Ayyasami 1979 Dubious Late Cretaceous Flag of India.svg India Suggested to be either an ornithischian (potentially stegosaurian) dinosaur or a plesiosaur
Eardasaurus Ketchum & Benson 2022 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom Had prominent enamel ridges in its teeth, which would indicate a diet of large prey Eardasaurus full skeleton.jpg
Edgarosaurus Druckenmiller 2002 Valid Early Cretaceous Flag of the United States.svg United States One of the first polycotylids to become native to the Western Interior Seaway Edgarosaurus.jpg
Eiectus Noè & Gómez-Pérez 2021 Valid? Early Cretaceous Flag of Australia (converted).svg Australia Potentially synonymous with Kronosaurus
Elasmosaurus Cope 1868 Valid Late Cretaceous Flag of the United States.svg United States Originally erroneously reconstructed with its skull placed at the end of its tail Elasmosaurus platyurus.png
Embaphias Cope 1894 Dubious Late Cretaceous Flag of the United States.svg United States Based on three cervical vertebrae
Eoplesiosaurus [9] Benson, Evans & Druckenmiller 2012 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom May have been the basalmost known member of the Plesiosauroidea Eoplesiosaurus antiquior.png
Eopolycotylus [15] Albright et al. 2007 Valid Late Cretaceous Flag of the United States.svg United States Known from a single partial skeleton Eopolycotylus rankini.png
Eretmosaurus Seeley 1874 Valid Early Jurassic to Middle Jurassic Flag of Russia.svg Russia
Flag of the United Kingdom.svg United Kingdom
Two species are known Eretmosaurus rugosus.png
Eromangasaurus Kear 2005 Valid Early Cretaceous Flag of Australia (converted).svg Australia The holotype skull is almost complete although badly crushed Eromangasaurus australis.png
Eurycleidus Andrews 1922 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom May have made a powerful forward stroke for fast swimming as suggested by its relatively large shoulder bones
Eurysaurus Gaudry 1878 Valid Early Jurassic Flag of France.svg France Formerly misidentified as a nothosaur
Fluvionectes Campbell et al. 2021 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada The holotype specimen may have died in a log jam as suggested by the pieces of coalified wood found alongside it Fluvionectes sloanae.png
Franconiasaurus [16] Sachs, Eggmaier & Madzia 2024 Valid Early Jurassic Flag of Germany.svg Germany Its cervical and dorsal vertebrae possessed short neural spines Franconiasaurus Life Restoration.jpg
Fresnosaurus Welles 1943 Valid Late Cretaceous Flag of the United States.svg United States Coexisted with at least three other plesiosaurs Fresnosaurus drescheri profile reconstruction.jpg
Futabasaurus Sato, Hasegawa & Manabe 2006 Valid Late Cretaceous Flag of Japan.svg Japan Most of its bones preserve bite marks caused by Cretalamna , indicating it would have been scavenged or hunted by the shark Futabasaurus suzukii.png
Gallardosaurus Gasparini 2009 Valid Late Jurassic Flag of Cuba.svg Cuba The only known individual was discovered in a concretion in dark shale Gallardosaurus Skeletal.svg
"Georgia"Otschev 1976 PreoccupiedN/AN/APreoccupied by a genus of snake, later renamed Georgiasaurus
Georgiasaurus Otschev 1977 Valid Late Cretaceous Flag of Russia.svg Russia The holotype skeleton was damaged during preparation of the quarry stone Georgiasaurus penzensis.png
Goniosaurus Meyer 1860 Valid Late Cretaceous Flag of the Netherlands.svg Netherlands The striations of its tooth meet each other under an angle pointing to the root instead of the apex
Gronausaurus [17] Hampe 2013 Jr. synonymN/AN/AJunior synonym of Brancasaurus
Hastanectes [18] Benson et al. 2012 Valid Early Cretaceous Flag of the United Kingdom.svg United Kingdom Originally named as a species of Cimoliasaurus Hastanectes valdensis.png
Hauffiosaurus O'Keefe 2001 Valid Early Jurassic Flag of Germany.svg Germany
Flag of the United Kingdom.svg United Kingdom
The holotype specimen is preserved lying on its back Hauffiosaurus zanoni.png
Hydralmosaurus Welles 1943 Jr. synonymN/AN/AJunior synonym of Styxosaurus
Hydrorion Großmann 2007 Valid Early Jurassic Flag of Germany.svg Germany Several individuals are known Hydrorion1DB.jpg
Hydrotherosaurus Welles 1943 Valid Late Cretaceous Flag of the United States.svg United States Multiple vertebrae were the first remains to be found. More bones had been unearthed afterwards Hydrotherosaurus NT.jpg
Ischyrodon von Meyer 1838 Dubious Middle Jurassic Flag of Switzerland (Pantone).svg  Switzerland Has been considered a junior synonym of Liopleurodon , but a 2022 revision found some differences that would make it separate from that genus [19] Ischyrodon meriani holotype tooth crown.jpg
Jucha Fischer et al. 2020 Valid Early Cretaceous Flag of Russia.svg Russia One of the earliest known confirmed elasmosaurids Jucha squalea.png
Kaiwhekea Cruickshank & Fordyce 2002 Valid Late Cretaceous Flag of New Zealand.svg New Zealand Preserved inside a large, roughly 6.5 m (21 ft) long concretion Kaiwhekea NT small.jpg
Kawanectes [20] O'Gorman 2016 Valid Late Cretaceous Flag of Argentina.svg Argentina Previously identified as a species of Trinacromerum Kawanectes lafquenianum.png
Kimmerosaurus Brown 1981 Valid Late Jurassic Flag of Norway.svg Norway?
Flag of the United Kingdom.svg United Kingdom
Its skull was overall similar to that of the related Cryptoclidus but much broader Kimmerosaurus.png
Kronosaurus Longman 1924 Valid Early Cretaceous Flag of Australia (converted).svg Australia One of the largest pliosaurids ever identified, likely the apex predator of its environment Kronosaurus queenslandicus SW.png
Lagenanectes Sachs, Hornung & Kear 2017 Valid Early Cretaceous Flag of Germany.svg Germany One of the most well-preserved plesiosaurs known from the Early Cretaceous of Europe Lagenanectes skeletal.png
Leivanectes Páramo-Fonseca et al. 2019 Valid Early Cretaceous Flag of Colombia.svg Colombia Differs from the contemporary Callawayasaurus , hence its classification as a separate genus
Leptocleidus Andrews 1922 Valid Early Cretaceous Flag of Australia (converted).svg Australia
Flag of South Africa.svg South Africa
Flag of the United Kingdom.svg United Kingdom
Like other members of its family and unlike most other plesiosaurs, it inhabited freshwater environments Leptocleidus capensis.png
Leurospondylus Brown 1913 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada Its exact taxonomic placement is uncertain Leurospondylus.jpg
Libonectes Carpenter 1997 Valid Late Cretaceous Flag of Morocco.svg Morocco
Flag of the United States.svg United States
Originally referred to as a species of Elasmosaurus , but it was named as a distinct genus due to morphological differences New Libonectes.jpg
Lindwurmia Vincent & Storrs 2019 Valid Early Jurassic Flag of Germany.svg Germany Possessed five pairs of premaxillary teeth Lindwurmia NT.png
Liopleurodon Sauvage 1873 Valid Middle Jurassic to Late Jurassic Flag of France.svg France
Flag of Germany.svg Germany
Flag of Mexico.svg Mexico
Flag of the United Kingdom.svg United Kingdom
Several analyses suggest that this genus may have been an ambush predator Liopleurodon after Tarlo.jpg
Lorrainosaurus [21] Sachs et al. 2023 Valid Middle Jurassic Flag of France.svg France Originally assigned to Simolestes but it has been found to be more derived Lorrainosaurus keileni holotype diagram.webp
Luetkesaurus Kiprijanoff 1883 Dubious Late Cretaceous Flag of Russia.svg Russia No species name has ever been assigned
Luskhan Fischer et al. 2017 Valid Early Cretaceous Flag of Russia.svg Russia Unlike other pliosaurids, it had a slender snout, small teeth, and short tooth rows, convergent with polycotylids Luskhan itilensis.jpg
Lusonectes Smith, Araújo & Mateus 2012 Valid Early Jurassic Flag of Portugal (official).svg Portugal The first plesiosaur named from Portugal Lusonectes.jpg
Macroplata Swinton 1930 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Its neck is comparatively longer than its head Macroplata BW.jpg
Makhaira [22] Fischer et al. 2015 Valid Early Cretaceous Flag of Russia.svg Russia Unusually, its teeth were triangular in cross-section Makhaira rossica.jpg
Manemergus Buchy et al. 2005 Valid Late Cretaceous Flag of Morocco.svg Morocco May have been contemporaneous with Thililua Manemergus anguirostris.png
Marambionectes [23] O'Gorman et al. 2024 Valid Late Cretaceous Antarctica Closely allied to the aristonectines Marambionectes molinai.png
Maresaurus Gasparini 1997 Valid Middle Jurassic Flag of Argentina.svg Argentina The first plesiosaur identified from the Los Molles Formation
Marmornectes Ketchum & Benson 2011 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom Would have been very similar to Peloneustes
Martinectes [24] Clark, O'Keefe & Slack 2023 Valid Late Cretaceous Flag of Russia.svg Russia?
Flag of the United States.svg United States
Initially named as species of Trinacromerum and then assigned to Dolichorhynchops until its reclassification as a new genus in 2023 Martinectes UMMNH.jpg
Mauisaurus Hector 1874 Dubious Late Cretaceous Flag of New Zealand.svg New Zealand Several specimens had been referred to this genus, but a 2017 review restricts it only to the lectotype [25] Mauisaurus BW.jpg
Mauriciosaurus Frey et al. 2017 Valid Late Cretaceous Flag of Mexico.svg Mexico Similarly to Cryptoclidus , it is noted for the unusual arrangement of gastralia Mauriciosaurus fernandezi life restoration.jpg
Megacephalosaurus [26] Schumacher et al. 2013 Valid Late Cretaceous Flag of the United States.svg United States One of the last known pliosaurids prior to their extinction Megacephalosaurus eulerti MP.png
Megalneusaurus Knight 1898 Valid Late Jurassic Flag of the United States.svg United States One specimen preserves stomach contents, including cephalopods and fish Megalneusaurus027.jpg
Meyerasaurus Smith & Vincent 2010 Valid Early Jurassic Flag of Germany.svg Germany Represented by a complete, articulated skeleton Rhomaleosaurus victor.jpg
Microcleidus Watson 1909 Valid Early Jurassic Flag of Germany.svg Germany
Flag of Luxembourg.svg Luxembourg
Flag of the United Kingdom.svg United Kingdom
Possessed at least forty vertebrae in its neck Microcleidus homalospondylus.png
Monquirasaurus Noè & Gómez-Pérez 2021 Valid Early Cretaceous Flag of Colombia.svg Colombia Originally known as a South American species of Kronosaurus Kronosaurus bojacens1DB.jpg
Morenosaurus Welles 1943 Valid Late Cretaceous Flag of the United States.svg United States The only described specimen is nearly complete, missing only the skull and some parts of the neck and paddles Morenosaurus stocki.png
Morturneria Chatterjee & Creisler 1994 Valid Late Cretaceous Antarctica Once considered to be a juvenile Aristonectes , but a 2017 study found it to be distinct enough to warrant recognition as separate [27] Morturneria seymourensis.png
Muraenosaurus Seeley 1874 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom May have possessed an increased muscle attachment towards its neck as indicated by its elongated cervical vertebrae with broad neural spines Muraenosaurus l2.jpg
Nakonanectes Serratos et al. 2017 Valid Late Cretaceous Flag of the United States.svg United States Its overall morphology was exceptionally similar to that of aristonectines despite being less derived Nakonanectes bradti.png
Nichollssaura [28] Druckenmiller & Russell 2009 Valid Early Cretaceous Flag of Canada (Pantone).svg Canada Fills a temporal gap of approximately 40 million years in the fossil record of North American plesiosaurs Nichollssaura BW.jpg
"Nichollsia"Druckenmiller & Russell 2008 PreoccupiedN/AN/APreoccupied by a genus of isopod, renamed Nichollssaura
Occitanosaurus Bardet et al. 1999 Jr. synonymN/AN/AJunior synonym of Microcleidus
Ogmodirus Williston & Moodie 1913 Dubious Late Cretaceous Flag of the United States.svg United States May be an elasmosaurid Ogdomirus holotype.jpg
Oligosimus Leidy 1872 Jr. synonymN/AN/AJunior synonym of Cimoliasaurus
Opallionectes Kear 2006 Valid Early Cretaceous Flag of Australia (converted).svg Australia Hypothesized to live on a cold habitat Opallionectes andamookaensis.png
Ophthalmothule Roberts et al. 2020 Valid Late Jurassic to Early Cretaceous Flag of Norway.svg Norway May have possibly hunted at night in deep waters as suggested by its relatively large eye sockets Ophthalmothule cryostea.png
Orophosaurus Cope 1851 Dubious Late Cretaceous Flag of the United States.svg United States Named based only on portions of three neck vertebrae
Pachycostasaurus Cruickshank et al. 1996 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom Its skeleton bears several unique features in most of the bones Pachycostasaurus recon.png
Pahasapasaurus Schumacher 2007 Valid Late Cretaceous Flag of the United States.svg United States Distinguishable by characters of its epipodial and palate bones Pahasapasaurus haasi.png
"Palmula" [15] Albright et al. 2007 PreoccupiedN/AN/APreoccupied by a genus of foraminifer, renamed Palmulasaurus
Palmulasaurus Albright et al. 2007 Valid Late Cretaceous Flag of the United States.svg United States Shared its environment with three other polycotylids Palmulasaurus quadratus.png
Pantosaurus Marsh 1893 Valid Late Jurassic Flag of the United States.svg United States One fossil preserves a partially digested ichthyosaur embryo within its stomach cavity Pantosaurus striatus.png
Peloneustes Lydekker 1889 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom Multiple specimens are known, including fairly complete material, which make it one of the most well-known pliosaurids Peloneustes SW.png
Peyerus Stromer 1935 Jr. synonymN/AN/AJunior synonym of Leptocleidus
Picrocleidus Andrews 1910 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom Previously synonymized with the coeval Muraenosaurus , but this has been cast into doubt Picrocleidus beloclis.png
Piptomerus Cope 1887 Jr. synonymN/AN/AJunior synonym of Cimoliasaurus
Piratosaurus Leidy 1865 Dubious Late Cretaceous Flag of Canada (Pantone).svg Canada Solely known from a single tooth which may have come from a polycotylid Piratosaurus holotype.jpg
Plesioelasmosaurus Schumacher & Everhart 2022 Valid Late Cretaceous Flag of the United States.svg United States Would have been relatively basal for an elasmosaurid Plesioelasmosaurus holotype elements.png
Plesionectes Sachs & Madzia 2025 Valid Early Jurassic Flag of Germany.svg Germany Preserved patches of soft tissue impressions that may indicate a dark coloration for this taxon Plesionectes (holotype, SMNS 51945).png
Plesiopharos Puértolas-Pascual et al. 2021 Valid Early Jurassic Flag of Portugal (official).svg Portugal The holotype was discovered next to a lighthouse Plesiopharos moelensis.png
Plesiopleurodon Carpenter 1996 Valid Late Cretaceous Flag of the United States.svg United States Initially believed to be a member of the Pliosauroidea Plesiopleurodon2DB.jpg
Plesiopterys O'Keefe 2004 Valid Early Jurassic Flag of Germany.svg Germany Displays an unusual combination of primitive and derived traits Plesiopterys wildi.png
Plesiosaurus De la Beche & Conybeare 1821 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom The first plesiosaur genus scientifically named and described. May be the most commonly found member in the Lias Group Plesiosaurus 3DB.jpg
Pliosaurus Owen 1841 Valid Late Jurassic to Early Cretaceous Flag of Norway.svg Norway
Flag of Russia.svg Russia
Flag of Ukraine.svg Ukraine
Flag of the United Kingdom.svg United Kingdom
The second specimen of P. funkei has been nicknamed "Predator X" Pliosaurus funkei21DB.jpg
Polycotylus Cope 1869 Valid Late Cretaceous Flag of Russia.svg Russia
Flag of the United States.svg United States
One particular specimen preserves a fetus inside of it, suggesting it gave live birth Polycotylus NT.jpg
Polyptychodon Owen 1841 Dubious Late Cretaceous Flag of Argentina.svg Argentina?
Flag of France.svg France?
Flag of the United Kingdom.svg United Kingdom
The sauropod dinosaur Dinodocus had been mistakenly attributed to this genus Polyptychodon interr2DB.jpg
"Raptocleidus"Evans 2012 Nomen nudum Early Jurassic Flag of the United Kingdom.svg United Kingdom Two species have been named, albeit informally
Rhaeticosaurus [29] Wintrich et al. 2017 Valid Late Triassic Flag of Germany.svg Germany One of the few plesiosaurs known from the Triassic
Rhomaleosaurus Seeley 1874 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom One of the largest early predatory marine reptiles. Four species are known Rhomaleosaurus crampt12DB.jpg
Sachicasaurus Páramo-Fonseca et al. 2018 Valid Early Cretaceous Flag of Colombia.svg Colombia One of the most completely known pliosaurids yet described Sachicasaurus Scale.svg
Scalamagnus [24] Clark, O'Keefe & Slack 2023 Valid Late Cretaceous Flag of the United States.svg United States Once believed to be a species of Dolichorhynchops Scalamagnus tropicensis.jpg
Scanisaurus Persson 1959 Dubious Late Cretaceous Flag of Russia.svg Russia
Flag of Sweden.svg Sweden
Although it is now considered dubious, this genus continues to be used in practice Scanisaurus Scale.svg
Seeleyosaurus White 1940 Valid Early Jurassic Flag of Germany.svg Germany
Flag of Russia.svg Russia?
Remains originally identified as Plesiosaurus SeeleysaurusDB.jpg
Serpentisuchops Persons, Street & Kelley 2022 Valid Late Cretaceous Flag of the United States.svg United States Had an exceptionally long neck, a unique trait among polycotylids Serpentisuchops pfisterae.png
Simolestes Andrews 1909 Valid Middle Jurassic to Late Jurassic Flag of India.svg India?
Flag of the United Kingdom.svg United Kingdom
Possessed an unusually short, high skull Simolestes1DB.jpg
Sinopliosaurus Young 1944 Dubious Early Cretaceous Flag of the People's Republic of China.svg China Based only on a tooth and three vertebrae
Spitrasaurus [30] Knutsen, Druckenmiller & Hurum 2012 Valid Late Jurassic Flag of Norway.svg Norway
Flag of the United Kingdom.svg United Kingdom?
Two species have been named Spitrasaurus wensaasi.png
Spondylosaurus Fischer 1845 Jr. synonymN/AN/AJunior synonym of Pliosaurus
Stenorhynchosaurus Páramo-Fonseca et al. 2016 Valid Early Cretaceous Flag of Colombia.svg Colombia Originally identified as a specimen of Brachauchenius Stenorhynchosaurus holotype skull.jpg
"Stereosaurus"Seeley 1869 Nomen nudum Late Cretaceous Flag of the United Kingdom.svg United Kingdom An informally named plesiosaur
Sthenarosaurus Watson 1909 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Its pelvis was relatively broad and strong Sthenarosaurus sp 2.JPG
Stratesaurus [9] Benson, Evans & Druckenmiller 2012 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Possibly the basalmost known rhomaleosaurid Holotype of Stratesaurus taylori OUMNH J.10337.png
Stretosaurus Tarlo 1959 Jr. synonymN/AN/AJunior synonym of Pliosaurus
Strongylokrotaphus Novozhilov 1964 Jr. synonymN/AN/AJunior synonym of Pliosaurus
Styxosaurus Welles 1943 Valid Late Cretaceous Flag of the United States.svg United States Closely related to Elasmosaurus , but can be differentiated from it based on morphological features Styxosaurus snowii.png
Sulcusuchus Gasparini & Spalletti 1990 Valid Late Cretaceous Flag of Argentina.svg Argentina Originally mistakenly believed to be a pseudosuchian Sulcusuchus erraini.png
Taphrosaurus Cope 1870 Dubious Late Cretaceous Flag of the United States.svg United States Poorly known
Tatenectes [31] O'Keefe & Wahl 2003 Valid Late Jurassic Flag of the United States.svg United States Its unusual body shape and pachyostotic gastralia would have made it more suitable to turbulence Tatenectes SW.png
Terminonatator Sato 2003 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada One of the youngest plesiosaurs known from the Western Interior Seaway Terminonatator ponteixensis.png
Thalassiodracon Storrs & Taylor 1996 Valid Late Triassic to Early Jurassic Flag of the United Kingdom.svg United Kingdom Its maxillae had heterodont dentition Thalassiodracon BW.jpg
Thalassiosaurus Welles 1953 Jr. synonymN/AN/AJunior synonym of Styxosaurus
Thalassomedon Welles 1943 Valid Late Cretaceous Flag of the United States.svg United States The type specimen has stones preserved in its stomach cavity Thalassomedon haningtoni.jpg
Thalassonomosaurus Welles 1943 Jr. synonymN/AN/AJunior synonym of Styxosaurus
Thaumatodracon Smith & Araújo 2017 Valid Early Jurassic Flag of the United Kingdom.svg United Kingdom Relatively large for a rhomaleosaurid
Thaumatosaurus von Meyer 1841 Jr. synonymN/AN/AThe holotype is dubious and not diagnostic, as it can be referred to as an indeterminate pliosauroid. The specimens that were assigned to this genus now belong to different taxa
Thililua Bardet, Suberbiola & Jalil 2003 Valid Late Cretaceous Flag of Morocco.svg Morocco The first polycotylid plesiosaur named from Africa Thililua longicollis.png
Traskasaura [32] O'Keefe et al. 2025 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada Before its formal scientific description, it has been variously referred to as the "Courtenay elasmosaur", "Puntledge elasmosaur", or "Haslam elasmosaur". Officially recognized as the Provincial Fossil of British Columbia Traskasaura sandrae.jpg
Tremamesacleis White 1940 Jr. synonymN/AN/AJunior synonym of Muraenosaurus
Trematospondylus Quenstedt 1858 Dubious Middle Jurassic Flag of Germany.svg Germany One of the first described plesiosaurs. Known only from seven large vertebrae
Tricleidus Andrews 1909 Valid Middle Jurassic Flag of the United Kingdom.svg United Kingdom One referred species has been later found to belong to Colymbosaurus [33] Tricleidus skeletal.jpg
Trinacromerum Cragin 1888 Valid Late Cretaceous Flag of Canada (Pantone).svg Canada
Flag of the United States.svg United States
May have preyed on small fish as suggested by its dentition Trinacromerum BW.jpg
Tuarangisaurus Wiffen, Wiffen & Moisley 1986 Valid Late Cretaceous Flag of New Zealand.svg New Zealand Possesses two features in its skeleton that are otherwise unknown in other elasmosaurids Tuarangisaurus keyesi.png
"Turneria"Chatterjee & Small 1989 PreoccupiedN/AN/APreoccupied by a genus of ant, renamed Morturneria
Umoonasaurus Kear, Schroeder & Lee 2006 Valid Early Cretaceous Flag of Australia (converted).svg Australia Uniquely for a plesiosaur, its skull features three crest-ridges that were likely covered in keratin Umoonasaurus demoscyllus.png
Unktaheela [24] Clark, O'Keefe & Slack 2023 Valid Late Cretaceous Flag of the United States.svg United States The smallest adult polycotylid yet known Unktaheela Skull Diagram.svg
Uronautes [34] Cope 1876 Dubious Late Cretaceous Flag of the United States.svg United States Described as a rhomaleosaurid but its extremely late age casts doubt into this
Vectocleidus [18] Benson et al. 2012 Valid Early Cretaceous Flag of the United Kingdom.svg United Kingdom Previously thought to belong to its relative Leptocleidus Leptocleidus1DB.jpg
Vegasaurus [35] O'Gorman et al. 2015 Valid Late Cretaceous Antarctica May be closely related to Morenosaurus Vegasaurus molyi.png
Vinialesaurus [36] Gasparini et al. 2002 Valid Late Jurassic Flag of Cuba.svg Cuba Originally referred to as a species of Cryptoclidus , but it was distinct enough from that genus to be named as its own taxon Vinialesaurus caroli.png
Westphaliasaurus Schwermann & Sander 2011 Valid Early Jurassic Flag of Germany.svg Germany Known from an articulated, almost complete skeleton Westphaliasaurus simonsensii.png
Woolungasaurus Persson 1960 Dubious Early Cretaceous Flag of Australia (converted).svg Australia Today considered an indeterminate elasmosaurid Woolungasaurus glendowerensis.png
Wunyelfia Otero et al. 2021 Valid Late Cretaceous Flag of Chile.svg Chile One of the few Patagonian plesiosaurs described from outside Argentina Wunyelfia maulensis profile reconstruction.jpg
Yuzhoupliosaurus [37] Zhang 1985 Valid Middle Jurassic Flag of the People's Republic of China.svg China Distinguishable by its long coracoids and well-developed clavicles
Zarafasaura Vincent et al. 2011 Valid Late Cretaceous Flag of Morocco.svg Morocco Unlike other elasmosaurids, its skull was unusually short Zarafasaura oceanis.png

See also

Footnotes

  1. See Haaramo, Plesiosauria.
  2. See Smith, Plesiosaur Genera.
  3. A. Yu. Berezin (2011). "A new plesiosaur of the family Aristonectidae from the early cretaceous of the center of the Russian platform". Paleontological Journal. 45 (6): 648–660. Bibcode:2011PalJ...45..648B. doi:10.1134/S0031030111060037. S2CID   129045087.
  4. Marcela Gómez-Pérez; Leslie F. Noè (2017). "Cranial anatomy of a new pliosaurid Acostasaurus pavachoquensis from the Lower Cretaceous of Colombia, South America". Palaeontographica Abteilung A. 310 (1–2): 5–42. Bibcode:2017PalAA.310....5G. doi:10.1127/pala/2017/0068.
  5. Tai Kubo; Mark T. Mitchell & Donald M. Henderson (2012). "Albertonectes vanderveldei, a new elasmosaur (Reptilia, Sauropterygia) from the Upper Cretaceous of Alberta". Journal of Vertebrate Paleontology. 32 (3): 557–572. Bibcode:2012JVPal..32..557K. doi:10.1080/02724634.2012.658124. S2CID   129500470.
  6. O'Gorman, Jose P.; Otero, Rodrigo A.; Hiller, Norton; O'Keefe, Robin F.; Scofield, R. Paul; Fordyce, Ewan (2021-03-04). "CT-scan description of Alexandronectes zealandiensis (Elasmosauridae, Aristonectinae), with comments on the elasmosaurid internal cranial features" . Journal of Vertebrate Paleontology. 41 (2). Bibcode:2021JVPal..41E3310O. doi:10.1080/02724634.2021.1923310. ISSN   0272-4634. S2CID   237518012.
  7. Andrea Cau & Federico Fanti (2015). "High evolutionary rates and the origin of the Rosso Ammonitico Veronese Formation (Middle-Upper Jurassic of Italy) reptiles". Historical Biology: An International Journal of Paleobiology. 28 (7): 952–962. doi:10.1080/08912963.2015.1073726. S2CID   86528030.
  8. Peggy Vincent & Roger B. J. Benson (2012). "Anningasaura, a basal plesiosaurian (Reptilia, Plesiosauria) from the Lower Jurassic of Lyme Regis, United Kingdom". Journal of Vertebrate Paleontology. 32 (5): 1049–1063. Bibcode:2012JVPal..32.1049V. doi:10.1080/02724634.2012.686467. S2CID   86547069.
  9. 1 2 3 Roger B. J. Benson; Mark Evans & Patrick S. Druckenmiller (2012). "High Diversity, Low Disparity and Small Body Size in Plesiosaurs (Reptilia, Sauropterygia) from the Triassic–Jurassic Boundary". PLOS ONE. 7 (3) e31838. Bibcode:2012PLoSO...731838B. doi: 10.1371/journal.pone.0031838 . PMC   3306369 . PMID   22438869.
  10. Benavides-Cabra, Cristian D.; Garavito-Camacho, Renzo A.; Páramo-Fonseca, María E.; Pomar, Daniel Eduardo (November 3, 2025). "A new brachaucheniine pliosaurid (Plesiosauria, Pliosauridae) from the upper Aptian of Villa de Leyva, Boyacá, Colombia". Historical Biology : 1–27. doi:10.1080/08912963.2025.2580967. ISSN   0891-2963.
  11. R. Araújo; M.J. Polcyn; A.S. Schulp; O. Mateus; L.L. Jacobs; A. Olímpio Gonçalves & M.-L. Morais (2015). "A new elasmosaurid from the early Maastrichtian of Angola and the implications of girdle morphology on swimming style in plesiosaurs". Netherlands Journal of Geosciences. 94 (1): 109–120. Bibcode:2015NJGeo..94..109A. doi: 10.1017/njg.2014.44 . S2CID   86616531.
  12. O'Gorman, José P.; Carignano, Ana Paula; Calvo-Marcilese, Lydia; Pérez Panera, Juan Pablo (2023-08-10). "A new elasmosaurid (Sauropterygia, Plesiosauria) from the upper levels of the La Colonia Formation (upper Maastrichtian), Chubut Province, Argentina". Cretaceous Research. 152 105674. Bibcode:2023CrRes.15205674O. doi:10.1016/j.cretres.2023.105674. ISSN   0195-6671. S2CID   260830333.
  13. Peggy Vincent; Nathalie Bardet & Emanuela Mattioli (2012). "A new pliosaurid from the Pliensbachian (Early Jurassic) of Normandy (Northern France)". Acta Palaeontologica Polonica. in press. doi: 10.4202/app.2011.0113 .
  14. Espen M. Knutsen; Patrick S. Druckenmiller & Jørn H. Hurum (2012). "A new plesiosauroid (Reptilia: Sauropterygia) from the Agardhfjellet Formation (Middle Volgian) of central Spitsbergen, Norway" (PDF). Norwegian Journal of Geology. 92 (2–3): 213–234. Archived from the original (PDF) on August 7, 2020.
  15. 1 2 PLESIOSAURS FROM THE UPPER CRETACEOUS (CENOMANIAN–TURONIAN) TROPIC SHALE OF SOUTHERN UTAH, PART 2: POLYCOTYLIDAE L. Barry Albright Iii, David D. Gillette, and Alan L. Titus, Journal of Vertebrate Paleontology, 2007, 27(1):41-58
  16. Sachs, Sven; Eggmaier, Stefan; Madzia, Daniel (2024-02-16). "Exquisite skeletons of a new transitional plesiosaur fill gap in the evolutionary history of plesiosauroids". Frontiers in Earth Science. 12. Bibcode:2024FrEaS..1241470S. doi: 10.3389/feart.2024.1341470 .
  17. Oliver Hampe (2013). "The forgotten remains of a leptocleidid plesiosaur (Sauropterygia: Plesiosauroidea) from the Early Cretaceous of Gronau (Münsterland, Westphalia, Germany)". Paläontologische Zeitschrift. 87 (4): 473–491. Bibcode:2013PalZ...87..473H. doi:10.1007/s12542-013-0175-3. S2CID   129834688.
  18. 1 2 Roger B. J. Benson; Hilary F. Ketchum; Darren Naish & Langan E. Turner (2013). "A new leptocleidid (Sauropterygia, Plesiosauria) from the Vectis Formation (Early Barremian–early Aptian; Early Cretaceous) of the Isle of Wight and the evolution of Leptocleididae, a controversial clade". Journal of Systematic Palaeontology. 11 (2): 233–250. Bibcode:2013JSPal..11..233B. doi:10.1080/14772019.2011.634444. S2CID   18562271.
  19. Madzia, D.; Sachs, S.; Klug, C. (2022). "Historical significance and taxonomic status of Ischyrodon meriani (Pliosauridae) from the Middle Jurassic of Switzerland". PeerJ. 10 e13244. doi: 10.7717/peerj.13244 . PMC   8995022 . PMID   35415018.
  20. José P. O'Gorman (2016). "A small body sized non-aristonectine elasmosaurid (Sauropterygia, Plesiosauria) from the Late Cretaceous of Patagonia with comments on the relationships of the Patagonian and Antarctic elasmosaurids". Ameghiniana. 53 (3): 245–268. doi:10.5710/AMGH.29.11.2015.2928. hdl: 11336/54311 . S2CID   133139689.
  21. Sachs, S.; Madzia, D.; Thuy, B.; Kear, B.P. (October 16, 2023). "The rise of macropredatory pliosaurids near the Early-Middle Jurassic transition". Scientific Reports. 13 (17558): 17558. Bibcode:2023NatSR..1317558S. doi: 10.1038/s41598-023-43015-y . PMC   10579310 . PMID   37845269.
  22. Valentin Fischer; Maxim S. Arkhangelsky; Ilya M. Stenshin; Gleb N. Uspensky; Nikolay G. Zverkov & Roger B. J. Benson (2015). "Peculiar macrophagous adaptations in a new Cretaceous pliosaurid". Royal Society Open Science. 2 (12) 150552. Bibcode:2015RSOS....250552F. doi:10.1098/rsos.150552. PMC   4807462 . PMID   27019740.
  23. O'Gorman, Jose P.; Canale, Juan I.; Bona, Paula; Tineo, David E.; Reguero, Marcelo; Cárdenas, Magalí (2024-12-31). "A new elasmosaurid (Plesiosauria: Sauropterygia) from the López de Bertodano Formation: new data on the evolution of the aristonectine morphology". Journal of Systematic Palaeontology . 22 (1). Bibcode:2024JSPal..2212302O. doi:10.1080/14772019.2024.2312302. ISSN   1477-2019.
  24. 1 2 3 Clark, Robert O.; O'Keefe, F. Robin; Slack, Sara E. (2023-12-24). "A new genus of small polycotylid plesiosaur from the Upper Cretaceous of the Western Interior Seaway and a clarification of the genus Dolichorhynchops" . Cretaceous Research . 157 105812. doi:10.1016/j.cretres.2023.105812. ISSN   0195-6671. S2CID   266546582.
  25. Hiller, Norton; O’Gorman, José P.; Otero, Rodrigo A.; Mannering, Al A. (2017). "A reappraisal of the Late Cretaceous Weddellian plesiosaur genus Mauisaurus Hector, 1874". New Zealand Journal of Geology and Geophysics. 60 (2): 112–128. Bibcode:2017NZJGG..60..112H. doi:10.1080/00288306.2017.1281317. S2CID   132037930.
  26. Bruce A. Schumacher; Kenneth Carpenter & Michael J. Everhart (2013). "A new Cretaceous Pliosaurid (Reptilia, Plesiosauria) from the Carlile Shale (middle Turonian) of Russell County, Kansas". Journal of Vertebrate Paleontology. 33 (3): 613–628. Bibcode:2013JVPal..33..613S. doi:10.1080/02724634.2013.722576. S2CID   130165209.
  27. O'Keefe, F. R.; Otero, R. A.; Soto-Acuña, S.; O'Gorman, J. P.; Godfrey, S. J.; Chatterjee, S. (2017). "Cranial anatomy of Morturneria seymourensis from Antarctica, and the evolution of filter feeding in plesiosaurs of the Austral Late Cretaceous". Journal of Vertebrate Paleontology. 37 (4) e1347570. Bibcode:2017JVPal..37E7570O. doi:10.1080/02724634.2017.1347570. hdl: 11336/75235 . S2CID   91144814.
  28. Druckenmiller, Patrick S.; Russell, Anthony P. (2009). "The new plesiosaurian genus Nichollssaura from Alberta, Canada: replacement name for the preoccupied genus Nichollsia". Journal of Vertebrate Paleontology. 29 (1): 276. Bibcode:2009JVPal..29..276D. doi:10.1080/02724634.2009.10010379. S2CID   83847722.
  29. Tanja Wintrich; Shoji Hayashi; Alexandra Houssaye; Yasuhisa Nakajima; P. Martin Sander (2017). "A Triassic plesiosaurian skeleton and bone histology inform on evolution of a unique body plan". Science Advances. 3 (12) e1701144. Bibcode:2017SciA....3E1144W. doi:10.1126/sciadv.1701144. PMC   5729018 . PMID   29242826.
  30. Espen M. Knutsen; Patrick S. Druckenmiller & Jørn H. Hurum (2012). "Two new species of long-necked plesiosaurians (Reptilia: Sauropterygia) from the Upper Jurassic (Middle Volgian) Agardhfjellet Formation of central Spitsbergen" (PDF). Norwegian Journal of Geology. 92 (2–3): 187–212. Archived from the original (PDF) on August 7, 2020.
  31. O'Keefe, F.R. & Street, H.P. 2009; "Osteology of the Cryptocleidoid Plesiosaur Tatenectes laramiensis, with Comments on the Taxonomic Status of the Cimoliasauridae" Journal of Vertebrate Paleontology29(1):48–57
  32. O'Keefe, F. Robin; Armour Smith, Elliott; Clark, Robert O.; Otero, Rodrigo A.; Perella, Anna; Trask, Patrick (2025-12-31). "A name for the Provincial Fossil of British Columbia: a strange new elasmosaur taxon from the Santonian of Vancouver Island". Journal of Systematic Palaeontology . 23 (1). doi:10.1080/14772019.2025.2489938. ISSN   1477-2019.
  33. Knutsen, E. M.; Druckenmiller, P. S.; Hurum, J. (2012). "Redescription and taxonomic clarification of 'Tricleidus' svalbardensis based on new material from the Agardhfjellet Formation (Middle Volgian)" (PDF). Norwegian Journal of Geology. 92: 175–186.
  34. E. D. Cope. 1876. On some extinct reptiles and Batrachia from the Judith River and Fox Hills Beds of Montana. Proceedings of the Academy of Natural Sciences of Philadelphia 28:340-359
  35. José P. O'Gorman; Leonardo Salgado; Eduardo B. Olivero & Sergio A. Marenssi (2015). "Vegasaurus molyi, gen. et sp. nov. (Plesiosauria, Elasmosauridae), from the Cape Lamb Member (lower Maastrichtian) of the Snow Hill Island Formation, Vega Island, Antarctica, and remarks on Wedellian Elasmosauridae". Journal of Vertebrate Paleontology. 35 (3) e931285. Bibcode:2015JVPal..35E1285O. doi:10.1080/02724634.2014.931285. hdl: 11336/53416 . S2CID   128965534.
  36. Gasparini, Z., Bardet, N., and Iturralde-Vinent, M. (2002). "A new cryptoclidid plesiosaur from the Oxfordian (Late Jurassic) of Cuba Archived 2010-07-02 at the Wayback Machine ". Geobios 35(2): 201-211.
  37. Zhang, Y (1985). A new plesiosaur from Middle Jurassic of Sichuan Basin. Vertebrata PalAsiatica 23: 235-240.

References