Sauropterygian genera

Wunyelfia is a genus of elasmosaurid plesiosaur, a type of long-necked marine reptile, that lived in the oceans of Late Cretaceous Chile. It contains one species, W. maulensis.

Pahasapasaurus is an extinct genus of polycotylid plesiosaurs from Late Cretaceous rocks of the United States. Distinctive features of the taxon include elongate epipodial bones (radius/ulna - tibia/fibula) and the nature of the palate bones (roof of the mouth). The genus contains two species; type species, Pahasapasaurus haasi, was named in 2007 based on remains from the late Cenomanian-aged Greenhorn Limestone of South Dakota, In 2025, a second species was named, Pahasapasaurus gillettei, based on a complete skull and partial skeleton from the early Turonian-aged Tropic Shale of Utah.

Picrocleidus is an extinct genus of plesiosaur from the Middle Jurassic Oxford Clay Formation (Callovian stage) of the United Kingdom.

Kawanectes (meaning "Kawas swimmer") is an extinct genus of elasmosaurid plesiosaur, a type of long-necked marine reptile, that lived in the marginal marine, probably estuarine, environment of Late Cretaceous Patagonia. The genus contains a single species, Kawanectes lafquenianum, described in 2016 by José P. O'Gorman.

Georgiasaurus ("Georgy's lizard"; after V. A. Otschev's father, Georgy Otschev, a geodesist who died shortly before Otschev published the description in 1976) is an extinct genus of plesiosaur from the Late Cretaceous of Russia. Otschev (or Ochev) originally named the specimen Georgia, but that name was preoccupied by the colubrid snake Georgia Baird & Girard, 1853. Originally a complete skeleton, the specimen, holotype POKM 11658 consisting of seven neck vertebrae, vertebral impressions, both scapulae and two limbs, was damaged in preparation of the quarry stone. It was found near the village

Leurospondylus is an extinct genus of plesiosaur from the Horseshoe Canyon Formation of Canada whose family is currently disputed, but is suggested to be Elasmosauridae.

Palatodonta is an extinct genus of neodiapsid reptile known from the early Middle Triassic (early Anisian stage) of the Netherlands. It was initially described in 2013 as a basal placodontiform closely related to a group of marine reptiles called placodonts, characterized by their crushing teeth and shell-like body armor. Under this interpretation, Palatodonta is transitional between placodonts and less specialized reptiles. Like placodonts, it has a row of large teeth on its palate, but while these teeth are thick and blunt in placodonts, Palatodonta has palatal teeth that are thin and pointe

Franconiasaurus (meaning "Franconia reptile") is an extinct genus of basal plesiosauroid plesiosaurs from the Early Jurassic of Germany. The genus contains a single species, F. brevispinus, known from two well-preserved three-dimensional skeletons.

Leivanectes is a genus of plesiosaurs of the family Elasmosauridae known from Late Aptian marine deposits in central Colombia. It contains a single species, L. bernadoi, which was described in 2019.

Nakonanectes bradti is an elasmosaurid plesiosaur of the late Cretaceous found in 2010 the state of Montana in the United States. It is one of the most recently known elasmosaurids to have lived in North America. Unlike other elasmosaurids, it has a relatively short neck.

thumb|left|Restoration

Atychodracon is an extinct genus of rhomaleosaurid plesiosaurian known from the Late Triassic - Early Jurassic boundary (probably early Hettangian stage) of England. It contains a single species, Atychodracon megacephalus, named in 1846 originally as a species of Plesiosaurus. The holotype of "P." megacephalus was destroyed during a World War II air raid in 1940 and was later replaced with a neotype. The species had a very unstable taxonomic history, being referred to four different genera by various authors until a new genus name was created for it in 2015. Apart from the destroyed holotype a

Sthenarosaurus (meaning "strong lizard") is an extinct genus of rhomaleosaurid pliosauroid discovered in the Toarcian-aged 'Main Alum Shale' (Commune subzone of Bifrons zone) in Whitby, England. The type species, Sthenarosaurus dawkinsi, was named and described in 1909 by D. M. S. Watson. The type specimen is MMUM LL 8023, a set of postcrania discovered in Whitby. Other indeterminate specimens are known, including a pectoral girdle (pictured in taxobox) described in 1911. Plesiosaurian fossils were acquired for the Manchester Museum by William Boyd Dawkins who is honoured by the specific name.

Ophthalmothule (meaning "eye of the north"), was a cryptoclidid plesiosaur dating to the latest Volgian (around the Jurassic-Cretaceous boundary), found in the Slottsmøya Member Lagerstätte of the Agardhfjellet Formation in Spitsbergen. The type species is O. cryostea.

Plesioelasmosaurus is an extinct genus of elasmosaurid plesiosaur from the Late Cretaceous (middle Cenomanian) Greenhorn Limestone of Kansas, United States. The genus contains a single species, P. walkeri, known from a partial skeleton.

Rhaeticosaurus (meaning 'Rhaetian lizard') is an extinct genus of basal pliosauroid from the Late Triassic (Rhaetian) rocks of the Exter Formation. The type and only species, R. mertensi, was named by Wintrich et al. in 2017. It is known from a partial articulated skeleton.

Martinectes is an extinct genus of polycotylid plesiosaur from the Late Cretaceous (Campanian stage) of North America and possibly European Russia. The genus contains a single species M. bonneri, known from multiple skeletons and skulls. Martinectes was historically considered to represent a species of the genus Trinacromerum and later Dolichorhynchops before it was moved to its own genus. It was a large polycotylid measuring around long.

Ogmodirus is an extinct genus of plesiosaur found in the Cenomanian-Turonian (Late Cretaceous) Greenhorn Limestone of Kansas. The type species, Ogmodirus martini, was named by Samuel Wendell Williston and Roy Lee Moodie in 1913.

Yunguisaurus is an extinct genus of pistosaur known from the Guizhou Province of China.

Bobosaurus is an extinct genus of sauropterygian reptile related to plesiosaurs. It is based on the holotype MFSN 27285, a partial skeleton found in early Carnian-aged rocks (early Late Triassic) of the Rio del Lago Formation, northeastern Italy. Bobosaurus was named in 2006 by Fabio M. Dalla Vecchia and the type species is B. forojuliensis. It may be a pistosaurid, or closer to Plesiosauria. A recent cladistic analysis found it to be a more basal pistosaur. It was a relatively large animal, with more than in length.

Orophosaurus is an dubious genus of elasmosaurid plesiosaur from the Late Cretaceous of New Mexico.

Unktaheela is an extinct genus of polycotylid plesiosaur from the Late Cretaceous Sharon Springs Formation of the United States. The genus contains a single species, U. , known from two skulls and partial skeletons. Unktaheela represents the smallest known polycotylid.

Anarosaurus is an extinct genus of pachypleurosaurs that lived in the Middle Triassic period (Anisian) and has been found in the Jena Formation and the Karlstadt Formation of Germany and the Winterswijk Quarry (Lower Muschelkalk) of The Netherlands. Two species are known: A. pumilio (the type species) and A. heterodontus. The holotype of A. pumilio was originally housed at the Institut und Museum fur Geologie und Palaontologie, Georg-August-Universitat, Gottingen, but can no longer be located today because it was lost or destroyed during World War II. Anarosaurus was a small reptile with an es

Alexeyisaurus is an extinct genus of possible plesiosaur known from the upper Triassic (lower-middle Norian age) of Wilczek Formation, Wilczek Land, of Franz Josef Land, Russia. It was first named by A. G. Sennikov and M. S. Arkhangelsky in 2010 and the type species is Alexeyisaurus karnoushenkoi. While considered an elasmosaur in the initial publication, it has been described as a "partial, poorly preserved, and undiagnostic sauropterygian skeleton" in subsequent publications.

Plesiopharos (derived from the Greek words πλησίος (plesios), "close" and φάρος (pharos), "lighthouse", because its holotype was found in the vicinity of a lighthouse + [from São Pedro de] Moel) is an extinct genus of plesiosaur from the Early Jurassic Coimbra Formation of Portugal. Specifically, it was discovered in São Pedro de Moel, Marinha Grande, from which the type species' binomial name, Plesiopharos moelensis, derives from.

Scalamagnus is an extinct genus of polycotylid plesiosaur from the Late Cretaceous Tropic Shale Formation of the United States. The genus contains a single species S. tropicensis, known from a skull and two partial skeletons. Scalamagnus was historically considered to represent a species of the genus Dolichorhynchops before it was moved to its own genus.

Cymatosaurus is an extinct genus of pistosauroid or nothosauriform sauropterygian. It is known to have been alive from the Early Triassic to the Middle Triassic period (latest Olenekian to Anisian stages) of Germany and they seem to originate from the Netherlands. It was small to medium-sized for an eosauropterygian, measuring long. thumb|left|Cymatosaurus and pachypleurosaur humeri

Thaumatodracon is a genus of rhomaleosaurid pliosaur from the early Jurassic found in the United Kingdom. It contains a single species, named by Adam Smith and Ricardo Araújo in 2017.

Dianopachysaurus is an extinct genus of pachypleurosaur known from the lower Middle Triassic (Anisian age) of Yunnan Province, southwestern China. It was found in the Middle Triassic Lagerstätte of the Guanling Formation. It was first named by Jun Liu, Olivier Rieppel, Da-Yong Jiang, Jonathan C. Aitchison, Ryosuke Motani, Qi-Yue Zhang, Chang-Yong Zhou and Yuan-Yuan Sun in 2011 and the type species is Dianopachysaurus dingi, thanking a Professor Ding for his help.

Chubutinectes (meaning "Chubut swimmer") is an extinct genus of elasmosaurid plesiosaur from the Late Cretaceous La Colonia Formation of Argentina. The genus contains a single species, C. carmeloi, known from a partial skeleton and associated gastroliths.

Traskasaura (meaning "Trask lizard") is an extinct genus of basal elasmosaurid plesiosaurs from the Late Cretaceous (Santonian age) Haslam Formation of British Columbia, Canada. The genus contains a single species, Traskasaura sandrae, known from three partial skeletons. It is the first elasmosaurid discovered in and named from British Columbia.

Brimosaurus (meaning "strong lizard") is an extinct genus of plesiosaur from the Late Cretaceous of what is now Arkansas. The type species is Brimosaurus grandis, first named by Joseph Leidy in 1854. The name Brimosaurus is a nomen dubium: the fossils consist of only a few isolated vertebrae, and in 1952 Welles proposed that Brimosaurus was actually synonymous with Cimoliasaurus (which itself is based on dubious material).

Eardasaurus is a genus of thalassophonean pliosaurid from the middle Jurassic Oxford Clay Formation. The animal would have measured over long (the tail was not fully preserved) and possessed a high amount of teeth relative to other pliosaurs. Its teeth show distinct ridges formed by the tooth enamel, some of which are very pronounced and similar to carinae, giving the teeth a cutting edge.

Marambionectes (meaning "Marambio Island swimmer") is an extinct genus of weddellonectian elasmosaurid plesiosaur from the Late Cretaceous López de Bertodano Formation of Antarctica. The genus contains a single species, M. molinai, known from a partial skeleton.

Eiectus is a potentially valid genus of extinct short-necked pliosaur that lived in the Early Cretaceous period. Fossil material has been recovered from the Wallumbilla Formation (Aptian) of Queensland was initially classified under the related genus Kronosaurus until 2021.

Serpianosaurus (meaning "Serpiano lizard") is an extinct genus of pachypleurosaurs known from the Middle Triassic (late Anisian and early Ladinian stages) deposits of Switzerland and Germany. It was a small reptile, with the type specimen of S. mirigiolensis measuring long.

Hanosaurus is an extinct genus of marine reptiles that existed during the Triassic period in what is now China. The type species is Hanosaurus hupehensis. It was a small animal, with specimens measuring long in total body length, which likely fed on soft-bodied prey.

Plesionectes (meaning "near swimmer") is an extinct genus of basal plesiosauroid plesiosaurs known from the Early Jurassic (Toarcian age) Posidonia Shale of Germany. The genus contains a single species, Plesionectes longicollum, known from a well-preserved, nearly complete skeleton.

Corosaurus is an extinct genus of pistosauroid known from Wyoming of the United States. The holotype measured about long, while larger specimens would have belonged to individuals measuring more than long.

thumb|left|Skull Odoiporosaurus is an extinct genus of pachypleurosaur known from the Middle Triassic (middle Anisian stage) Besano Formation (Grenzbitumenzone) of northern Italy. It contains a single species, Odoiporosaurus teruzzii. Odoiporosaurus is the sister taxon of the group formed by Serpianosaurus and Neusticosaurus, and together with the older and more primitive Dactylosaurus plus Anarosaurus clade, they form a monophyletic group of European pachypleurosaurids.

Dactylosaurus is a genus of nothosaur in the family Pachypleurosauridae. Along with Anarosaurus, Dactylosaurus was one of the earliest known pachypleurosaurs to come from Europe.

Simosaurus is an extinct genus of marine reptile within the superorder Sauropterygia from the Middle Triassic of central Europe. Fossils have been found in deposits in France and Germany that are roughly 230 million years old. It is usually classified as a nothosaur, but has also been considered a pachypleurosaur or a more primitive sauropterygian.

Pararcus is an extinct genus of placodont marine reptile from the Middle Triassic of the Netherlands. The genus is monotypic and the type species is Pararcus diepenbroeki. Pararcus is known from a holotype skeleton about long from the Lower Muschelkalk of Winterswijk.

Parahenodus (meaning "near Henodus", with Henodus meaning "single tooth") is an extinct genus of henodontid placodont only known from a skull, discovered between 2008 and 2015 and described in 2018. It lived during the Late Triassic (Carnian–Norian). The skull, named and described as Parahenodus atancensis, was discovered in Keuper Facies of the Castilian Branche of the Iberian Range in the reservoir of El Atance (Sigüenza, Spain). It was the sister taxon to Henodus.