Sauropterygian genera

Edgarosaurus is a genus of polycotylid plesiosaur from the Thermopolis Shale, containing one species, E. muddi. The type specimen was found in Early Cretaceous (late Albian) rocks in the state of Montana in the United States. At the time, this location was covered by part of the Western Interior Seaway. Edgarosaurus was one of the first polycotylids that evolved to become native to the Western Interior Seaway.

Sachicasaurus is an extinct genus of brachauchenine pliosaurid known from the Barremian of the Paja Formation, Altiplano Cundiboyacense in the Colombian Eastern Ranges of the Andes. The type species is S. vitae.

Marmornectes is a genus of pliosaurid known from the Middle Jurassic of Bedfordshire, United Kingdom.

Sulcusuchus is a genus of polycotylid plesiosaur from the Maastrichtian of Argentina.

Callawayasaurus is a genus of plesiosaur from the family Elasmosauridae. When the holotype was first described by Samuel Paul Welles in 1962, it was described as Alzadasaurus colombiensis before being moved into its current genus by Kenneth Carpenter in 1999.

Cryonectes is an extinct genus of pliosaurid plesiosaurian known from the Early Jurassic of Normandy, northern France.

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.

Plesiopterys (“plesio” meaning “near,” and “pterys” meaning “wing” or “pterygoid bone”) is an extinct genus of plesiosaur originating from the Posidonienschiefer of Holzmaden, Germany, and lived during the Early Jurassic period. The type and only species is P. wildi, known from two immature specimens with the subadult measuring long. It possesses a unique combination of both primitive and derived characters, and is currently displayed at the State Museum of Natural History and the Hauff Museum, Germany.

Jucha is an extinct genus of plesiosaur found in the Hauterivian (Early Cretaceous) Klimovka Formation of Russia. The type species, J. squalea, was one of the basalmost and oldest definitive elasmosaurs known to date.

Tricleidus is an extinct genus of cryptoclidid plesiosaur known from only specimen (BMNH R3539) from the middle Jurassic of United Kingdom. It was first named by Andrews in 1909 and the type species is Tricleidus seeleyi. left|thumb|Skeletal diagram

Borealonectes is a genus of rhomaleosaurid pliosauroid, a type of plesiosaur. Its fossils were found in the Callovian-age (Middle Jurassic, about 165-161 million years ago) Hiccles Cove Formation of Melville Island, Canada, one of the islands in the Canadian Arctic Archipelago. It is based on a skull, neck vertebrae, and the right forelimb of one individual. Named in 2008 by Sato and Wu, Borealonectes is one of the few plesiosaurs known from the Jurassic of North America, and the first marine reptile from the Canadian Arctic with a well-preserved skull. The type species is B. russelli.

Opallionectes andamookaensis (meaning "the opal swimmer from Andamooka") is the name given to a 5 m (16 ft) long cryptoclidian plesiosaur, which is thought to have lived during the early Cretaceous period (Lower middle Aptian), 115 million years ago, in shallow seas covering what is now Australia.

Eretmosaurus (meaning "oar lizard") is an extinct genus of plesiosaur from the Early and Middle Jurassic of England and Russia. Two species are known: E. rugosus and E. dubius.

Wapuskanectes is an extinct genus of early elasmosaurid known from Alberta, Canada, in the Albian aged Wabiskaw member of the Clearwater Formation.

Spitrasaurus is an extinct genus of cryptoclidid plesiosauroid plesiosaur known from the uppermost Jurassic of central Spitsbergen, Norway and likely also Kimmeridge, England. It is named after a syllabic abbreviation for Spitsbergen Travel. Two species have been named: Spitrasaurus wensaasi, honouring volunteer Tommy Wensås, and Spitrasaurus larseni honouring volunteer Stig Larsen.

Terminonatator (meaning "last swimmer") is a genus of elasmosaurid plesiosaur from the Late Cretaceous of Saskatchewan, Canada. It is known from a skull and partial skeleton from a young adult, found in the Campanian-age Bearpaw Formation near Notukeu Creek in Ponteix. Terminonatator is currently one of the youngest plesiosaurs from the Western Interior Seaway.

Pantosaurus ("all lizard") is an extinct genus of plesiosaur from the Late Jurassic (Oxfordian) of what is now Wyoming. It lived in what used to be the Sundance Sea. It was originally named Parasaurus ("near lizard") by Othniel Charles Marsh in reference to Plesiosaurus, but that name was preoccupied, and Marsh changed it. The species Muraenosaurus reedii is in fact a junior synonym of Pantosaurus. The holotype YPM 543 is a partial articulated skeleton, partially prepared to yield a distal humerus, four articulated carpals, a fragment of the coracoid, and several isolated cervical vertebrae fr

Archaeonectrus is an extinct genus of pliosaur from the Early Jurassic (Sinemurian) of what is now southeastern England. The type species is Archaeonectrus (originally "Plesiosaurus") rostratus, first named by Sir Richard Owen in 1865, which was moved to its own genus by N.I. Novozhilov in 1964. It was a relatively small plesiosaur, measuring long. thumb|left|Additional specimen

Paraplacodus broilii is an extinct placodont sauropterygian from the Middle Triassic epoch, from the Anisian until Ladinian stages. The fossils were uncovered in Northern Italy and the species was named in 1931 by Bernhard Peyer. Paraplacodus means "Almost Placodus", in reference to its similarity to Placodus. thumb|left|Restoration thumb|left|Paraplacodus broilii fossil

Fluvionectes (meaning "river swimmer", from both Latin and Greek) is a genus of elasmosaurid plesiosaur found in the Dinosaur Park Formation in Alberta, Canada.

Acostasaurus (meaning "Acosta's lizard") is an extinct genus of possibly Thalassophonean pliosaurid known from the Barremian of the Paja Formation, Colombia. The type specimen, UNDG R-1000, is known from a near complete skull, and postcranial elements including a complete hindlimb and various vertebrae. The specimen has an estimated size of over in length.

Thililua is a genus of polycotylid plesiosaur, containing one species, T. longicollis.

Keichousaurus (meaning "Kweichow lizard") is an extinct genus of pachypleurosaurian marine reptile from the Chialingchiang and Falang Formations of China with two known species attributed to the genus: K. hui and K. yuananensis.

Zarafasaura is an extinct genus of elasmosaurid known from the Ouled Abdoun Basin of Morocco. As a relatively small elasmosaur, it would have measured around long and weighed about .

Lagenanectes is a genus of elasmosaurid plesiosaur from the Lower Cretaceous, found in Lower Saxony, Germany. The only species, Lagenanectes richterae, was first described in 2017, and is regarded as one of the best-preserved plesiosaur fossils from this geological age in Europe. Lagenanectes is one of the earliest elasmosaurids. The holotype is an incomplete skeleton, comprising large parts of the skull, some neck and tail vertebrae as well as ribs and part of the limbs. A length of about 8 meters (26 feet) has been estimated.

Pachycostasaurus (meaning 'thick-ribbed lizard') is an extinct Pliosauroid from the Oxford Clay formation of Peterborough, England.

Stenorhynchosaurus is an extinct genus of pliosaurid plesiosaurs which lived in the Early Cretaceous of South America. The type species and only known is Stenorhynchosaurus munozi.

Yuzhoupliosaurus is an extinct genus of plesiosaur from the Middle Jurassic of China. The genus is known only from a lower jaw, eighteen vertebrae, fragments of a pectoral girdle and parts of the right hindlimb. It is believed this genus lived in fresh water.

Polycotylus is a genus of plesiosaur within the family Polycotylidae. The type species is P. latippinis and was named by American paleontologist Edward Drinker Cope in 1869. Eleven other species have been identified. The name means 'much-cupped vertebrae', referring to the shape of the vertebrae. It lived in the Western Interior Seaway of North America toward the end of the Cretaceous. One fossil preserves an adult with a single large fetus inside of it, indicating that Polycotylus gave live birth, an unusual adaptation among reptiles. ==History==

Maresaurus is an extinct genus of plesiosaur from the Middle Jurassic (Bajocian) Los Molles Formation of Argentina. The type species, Maresaurus coccai, was named by Gasparini in 1997. Recent phylogenetic analysis found Maresaurus to be a rhomaleosaurid.

Cardiocorax is an extinct genus of elasmosaurid known from the Late Cretaceous (early Maastrichtian stage) Mocuio Formation of Namibe Province, southern Angola. It contains a single species, Cardiocorax mukulu.

Tatenectes is a genus of cryptoclidid plesiosaur known from the Upper Jurassic of Wyoming. Its remains were recovered from the Redwater Shale Member of the Sundance Formation, and initially described as a new species of Cimoliosaurus by Wilbur Clinton Knight in 1900. It was reassigned to Tricleidus by Maurice G. Mehl in 1912 before being given its own genus by O'Keefe and Wahl in 2003. Tatenectes laramiensis is the type and only species of Tatenectes. While the original specimen was lost, subsequent discoveries have revealed that Tatenectes was a very unusual plesiosaur. Its torso had a flatte

Anningasaura is an extinct genus of basal plesiosaur. It is known from a single type species, A. lymense, discovered in Early Jurassic rocks of Lyme Regis in the United Kingdom.

Morturneria is an extinct genus of plesiosaur from the Late Cretaceous of what is now Antarctica.

Luskhan (meaning "water spirit chief") is an extinct genus of large pliosaurid plesiosaurs from the Lower Cretaceous of western Russia. The only known species is L. itilensis, first described in 2017 from a well-preserved and nearly complete skeleton discovered in the Ulyanovsk region. As an early-diverging brachauchenine, Luskhan consequently exhibits an intermediate combination of traits seen in more basal (less specialized) and more derived (more specialized) pliosaurs. However, Luskhan departs significantly from other pliosaurs in that it exhibits a lack of adaptations in its skull to feed

Eopolycotylus is a genus of polycotylid plesiosaur known from the Cenomanian-age Tropic Shale of Utah.

Anguanax is an extinct genus of basal pliosaurid known from the Late Jurassic (Oxfordian stage) Rosso Ammonitico Veronese Formation of northern Italy. It contains a single species, Anguanax zignoi, known from a partially complete individual, representing the first articulated skeleton of an Italian plesiosaurian.

Djupedalia is an extinct genus of cryptoclidid plesiosauroid plesiosaur known from the uppermost Jurassic of central Spitsbergen, Norway. It is named after Øystein Djupedal, the former Minister of Education and Research who helped fund the fossil excavation with a budget of 1.2 million Norwegian kroner.

Alexandronectes is a genus of elasmosaurid plesiosaur, a type of long-necked marine reptile, that lived in the oceans of Late Cretaceous New Zealand. It contains one species, A. zealandiensis. Fossils of Alexandronectes were found in the Conway Formation of Canterbury, which can be dated to the Early Maastrichtian stage of the Cretaceous. Fossils of it were found around 1872 near the Waipara River, north of Christchurch, New Zealand.

Palmulasaurus is a genus of polycotylid plesiosaur from the Turonian Tropic Shale of Utah. It was originally described as Palmula, but that name was already occupied by a genus of Cretaceous foraminifera first described in 1833.

thumb|left|Size (green) compared to a human Vectocleidus is an extinct genus of leptocleidid plesiosaurian known from the Early Cretaceous Vectis Formation (late Barremian stage) of Isle of Wight, in the United Kingdom. It contains a single species, Vectocleidus pastorum.

Monquirasaurus ("Monquirá lizard") is an extinct genus of giant short-necked pliosaurs who lived during the Early Cretaceous (Aptian) in what is now Colombia. One species is known, M. boyacensis, described in 2021 from an almost complete fossil skeleton, discovered in 1977 in the town of Villa de Leyva, located in Boyacá. Published descriptions of the holotype specimen estimate that it should reach a total size approaching in length and weighing , making Monquirasaurus a large representative of the pliosaurids.

Stratesaurus is an extinct genus of small-bodied basal plesiosaur known from the Early Jurassic period (most likely earliest Hettangian stage) of the United Kingdom. It contains a single species, S. taylori. It was a small plesiosaur, with a skull length of and a body length of .

Arminisaurus (meaning "lizard of Arminius") is a genus of pliosaurid plesiosaur that lived during the Lower Jurassic in present-day Germany. With Westphaliasaurus and Cryonectes, Arminisaurus is only the third plesiosaurian taxon that was described from the Pliensbachian stage. The holotype and only known specimen is a fragmentary skeleton (about 40 percent complete), comprising an incomplete lower jaw, teeth, vertebrae and elements from the pectoral girdle and the paddles. The animal had an estimated body length of .

Westphaliasaurus is an extinct genus of plesiosaur from Lower Jurassic (Pliensbachian stage) deposits of Westphalia, northwestern Germany. It is known from a nearly complete and articulated skeleton missing the skull and about 38% of the upper neck vertebrae.

Serpentisuchops (meaning "snaky crocodile-face") is a genus of polycotylid plesiosaur from the late Cretaceous Pierre Shale of Wyoming, United States. The genus contains a single species, S. pfisterae, known from a partial skeleton.

Vinialesaurus is a genus of plesiosaur from the Late Jurassic (Oxfordian) Jagua Formation of Pinar del Río, Cuba. The combinatio nova of the type species is Vinialesaurus caroli, first described as the subspecies Cryptocleidus? cuervoi caroli by Ricardo De la Torre and Luis Rojas in 1949 under the holotype MNHNCu P 3008, and redescribed by Zulma Gasparini, Bardet and Iturralde in 2002. The authors of the 2002 paper considered Vinialesaurus distinct enough from Cryptocleidus to warrant its own genus, but it was a cryptoclidid.

Avalonnectes is an extinct genus of small-bodied rhomaleosaurid known from the Early Jurassic period (most likely earliest Hettangian stage) of the United Kingdom. It contains a single species, A. arturi.

thumb|left|Skull thumb|left|Life restoration Manemergus is a genus of polycotylid plesiosaur from the Late Cretaceous (Turonian) of Morocco. Manemergus was described in 2005 and contains only one species, M. anguirostris. The type specimen was discovered close to the town of Goulmima (Tizi-n-Imnayen) in Morocco's High Atlas mountains, in the same locality as another polycotylid, Thililua, was discovered.

Hastanectes is an extinct genus of a plesiosaurian with possible pliosaurid affinities known from the Early Cretaceous Wadhurst Clay Formation (Valanginian stage) of the United Kingdom. It contains a single species, Hastanectes valdensis, which was originally thought to be a species of Cimoliasaurus.

Bathyspondylus is an extinct genus of plesiosaur from the Kimmeridge Clay Formation of Swindon, England. Because it is known only from its fossil vertebrae (and so few of those have been recovered), paleontologists are not entirely sure of the taxonomy of Bathyspondylus; the family it belongs to is not currently known. The type, and only known, species is B. swindoniensis, which was described from the same material as its genus.

Seeleyosaurus is an extinct genus of plesiosaur from Germany and possibly also Russia.

thumb|left|Several Neusticosaurus pusillus at the Museum für Naturkunde, Berlin thumb|left|Neusticosaurus edwardsii

Augustasaurus is an extinct genus of sauropterygians that lived during the Anisian stage of the Middle Triassic in what is now North America. Only one species is known, A. hagdorni, described in 1997 from fossils discovered in the Favret Formation, Nevada, USA.

Eoplesiosaurus is an extinct genus of basal plesiosaur known from the Early Jurassic period (most likely earliest Hettangian stage) of the United Kingdom. It contains a single species, E. antiquior.

Vegasaurus is an extinct genus of elasmosaurid plesiosaur known from the Late Cretaceous (early Maastrichtian stage) Snow Hill Island Formation of Vega Island, Antarctic Peninsula. It contains a single species, Vegasaurus molyi.

Lusonectes (meaning "Portuguese swimmer") is an extinct genus of microcleidid plesiosaur from the Early Jurassic (Toarcian) São Gião Formation of Portugal.

species of reptile (fossil)

Mauriciosaurus (meaning "Mauricio [Fernández Garza's] reptile") is a genus of polycotylid plesiosaur from the Late Cretaceous of Mexico. It contains a single species, M. fernandezi (also named after Fernández Garza), described in 2017 by Eberhard Frey and colleagues from a single well-preserved juvenile specimen about long. Morphologically, it is overall most similar to the polycotyline polycotylids Trinacromerum and Dolichorhynchops. However, several features separate Mauriciosaurus from all other polycotylids, warranting the naming of a new genus. These include the sophisticated pattern of r

Goniosaurus is an extinct genus of plesiosaur from the Late Cretaceous (Maastrichtian age) of the Nekum Chalk, in the Netherlands. The only species so far described, G. binkhorsti is represented only by an isolated, compressed and slender tooth described by Christian Erich Hermann von Meyer and a referred tooth and possibly two cervical vertebrae that shows that it was an elasmosaurid, as many other Late Cretaceous plesiosaurs from Europe. The generic name is derived from the Greek gonia, "angle", referring to the fact that the striations meets each other under an angle pointing to below, i.e.