This list of informally named Mesozoic reptiles is a listing of prehistoric

reptiles Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and Amniotic egg, amniotic development. Living traditional reptiles comprise four Order (biology), orders: Testudines, Crocodilia, Squamata, and Rhynchocepha ...

from the

Mesozoic The Mesozoic Era is the Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceous Period (geology), Periods. It is characterized by the dominance of archosaurian r ...

era (excluding

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

s) that have never been given formally published

scientific names In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

. This list only includes names that were not properly published (" unavailable names") and have not since been published under a valid name. The following types of names are present on this list: * ''

Nomen nudum In Taxonomy (biology), taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published ...

'', Latin for "naked name": A name that has appeared in print but has not yet been formally published by the standards of the

International Commission on Zoological Nomenclature The International Commission on Zoological Nomenclature (ICZN) is an organization dedicated to "achieving stability and sense in the scientific naming of animals". Founded in 1895, it currently comprises 26 commissioners from 20 countries. Orga ...

. ''Nomina nuda'' (the plural form) are invalid, and are therefore not italicized as a proper generic name would be. * '' Nomen manuscriptum'', Latin for "manuscript name": A name that appears in manuscript but was not formally published. A ''nomen manuscriptum'' is equivalent to a ''nomen nudum'' for everything except the method of publication, and description. * '' Nomen ex dissertationae'', Latin for "dissertation name": A name that appears in a dissertation but was not formally published. * Nicknames or descriptive names given to specimens or taxa by researchers or the press.

A

Addyman plesiosaur

The "Addyman plesiosaur" is an informal name given to a leptocleidid

plesiosaur The Plesiosauria or plesiosaurs are an Order (biology), order or clade of extinct Mesozoic marine reptiles, belonging to the Sauropterygia. Plesiosaurs first appeared in the latest Triassic Period (geology), Period, possibly in the Rhaetian st ...

specimen (SAM P15980) discovered by the

opal Opal is a hydrated amorphous form of silicon dioxide, silica (SiO2·''n''H2O); its water content may range from 3% to 21% by weight, but is usually between 6% and 10%. Due to the amorphous (chemical) physical structure, it is classified as a ...

miners John and Molly Addyman in 1967 from the Bulldog Shale near

Andamooka, South Australia Andamooka is a town approximately 600 km north of Adelaide in the Far North of South Australia on the lands of the Kokatha people. Andamooka is the largest town administered by the Outback Communities Authority instead of a local governm ...

. Assigned to as cf. '' Leptocleidus'' sp. in 2007, probably a juvenile ''

Umoonasaurus ''Umoonasaurus'' is an extinct genus of plesiosaur belonging to the family Leptocleididae. This genus lived approximately 115 million years ago during the Early Cretaceous period (Aptian-Albian stages), in shallow seas covering parts of what is n ...

'', this 80% complete skeleton measures long and represents one of the most immature and smallest known plesiosaur specimens. Housed in the

South Australian Museum The South Australian Museum is a natural history museum and research institution in Adelaide, South Australia, founded in 1856 and owned by the Government of South Australia. It occupies a complex of buildings on North Terrace in the cultur ...

, the "Addyman plesiosaur" is also dubbed "the finest known opalised skeleton on Earth".

African pterosaur

The "African pterosaur" is an informal name given to a

pterosaur Pterosaurs are an extinct clade of flying reptiles in the order Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 million to 66 million years ago). Pterosaurs are the earli ...

specimen from the

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

of Niger, which was reported by Paul Sereno's team. The specimen is stated to be a partial wing, which is the first known in Africa, and its life-size reconstruction can be seen in the "GIANTS" exhibit in Chicago; although it is unstated which type of pterosaur this specimen belongs to, it is noted to be a

piscivore A piscivore () is a carnivorous animal that primarily eats fish. Fish were the diet of early tetrapod evolution (via water-bound amphibians during the Devonian period); insectivory came next; then in time, the more terrestrially adapted repti ...

(fish-eater) based on associated teeth material and similar to the pterosaurs known from Brazil of South America, with an estimated wingspan of . The specimen was later shown in the 2-hour

National Geographic ''National Geographic'' (formerly ''The National Geographic Magazine'', sometimes branded as ''Nat Geo'') is an American monthly magazine published by National Geographic Partners. The magazine was founded in 1888 as a scholarly journal, nine ...

special program ''Sky Monsters'' (2006), which featured its discovery and life-size reconstruction attempt by Sereno's team. In his update entry of the 2000 Expedition of Niger, Sereno mentioned that his team found evidence of a large pterosaur specimen. In his 2000 interview, David Blackburn who participated in that expedition recounted the pterosaur partial wing discovery. He later discussed about the

Elrhaz Formation The Elrhaz Formation is a geological Formation (geology), formation in Niger, West Africa. Its strata date back to the Early Cretaceous, about 125 to 112 million years ago. Dinosaur remains are among the fossils that have been recovered from the ...

pterosaur specimens in a 2002

conference abstract An abstract is a brief summary of a research article, thesis, review, conference proceeding, or any in-depth analysis of a particular subject and is often used to help the reader quickly ascertain the paper's purpose. When used, an abstract always ...

, stated to be the "only documented pterosaurian appendicular material from Africa", with the left humerus belonging to a tapejaroid and the partial wing belonging to an

anhanguerid Anhangueridae (alternatively called Ornithocheiridae, meaning "bird hands") is a group of pterosaurs within the suborder Pterodactyloidea. These pterosaurs were among the last to possess teeth. Members that belong to this group lived from the ...

Aktisaurus

"Aktisaurus" (meaning coast or shoreline lizard) is a ''nomen ex dissertationae'' created by Hallie Pritchett Street in their PhD thesis as a new genus to contain the species originally named ''

Mosasaurus conodon ''Mosasaurus'' (; "lizard of the Meuse (river), Meuse River") is the type genus (defining example) of the mosasaurs, an extinct group of aquatic Squamata, squamate reptiles. It lived from about 82 to 66 million years ago during the Campanian an ...

'' (specimen AMNH 1380), which has been of uncertain classification since its naming. The phylogenetic analysis of Street did not recover ''Mosasaurus'' as a

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

, and erected several new genera for species previously assigned to ''Mosasaurus''. "Aktisaurus" was recovered as the

sister taxon In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

of ''

Plotosaurus ''Plotosaurus'' ("swimmer lizard") is an extinct genus of large mosasaurs which lived during the Upper Cretaceous (Maastrichtian) in what is now North America. The taxon was initially described by University of California, Berkeley, Berkeley pale ...

'' as demostrated by the similar morphology of the carinae on their teeth.

Amblyrhynchosaurus

"Amblyrhynchosaurus wiffeni" (meaning blunt-snouted lizard) is a

and

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of ''nomen ex dissertationae'' named by Hallie Pritchett Street in their PhD thesis centered on the taxonomy of ''

Mosasaurus ''Mosasaurus'' (; "lizard of the Meuse (river), Meuse River") is the type genus (defining example) of the mosasaurs, an extinct group of aquatic Squamata, squamate reptiles. It lived from about 82 to 66 million years ago during the Campanian an ...

''. The designated

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

is NZGS CD 535, which is a mostly complete mosasaurine skull that was discovered in the Maungataniwha Sandstone on the

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

. "Amblyrhynchosaurus" has similar skull morphology to the genus ''

Prognathodon ''Prognathodon'' is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Mosasaurinae subfamily, alongside genera like ''Mosasaurus'' and ''Clidastes''. ''Prognathodon'' has been recovered from depos ...

'', but it was recovered as the

of '' Moanasaurus'' and a close relative of ''Mosasaurus''. The species epithet is in honor of

Joan Wiffen Joan Wiffen (née Pederson; 4 February 1922 – 30 June 2009) was a self-taught New Zealand paleontologist known for discovering the first dinosaur fossils in New Zealand. Early life Wiffen was born in 1922 and was brought up in Havelock North, ...

, although the precise spelling is uncertain. It is spelled both as "wiffeni" and "wiffenae" in the text of the thesis.

Antipodenectes

"Antipodenectes" (meaning swimmer from the other side of the world) is a ''nomen ex dissertationae'' erected by Hallie Pritchett Street in their PhD thesis to contain the species ''

mokoroa'', which was named by S.P. Welles and D.R. Gregg in 1971. In their

phylogenetic analysis In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data ...

, Street did not recover ''M. mokora'' as being within a

''Mosasaurus'' genus, so named a new genus to contain this taxon. It was recovered as a close relative of ''

'' as well as " Aktisaurus". The

is CM Zfr-1, which was discovered in the Conway Formation from the

South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North Island and Stewart Island. It is bordered to the north by ...

Aust Colossus

The "Aust Colossus" is an informal name given to the giant

ichthyosaur Ichthyosauria is an order of large extinct marine reptiles sometimes referred to as "ichthyosaurs", although the term is also used for wider clades in which the order resides. Ichthyosaurians thrived during much of the Mesozoic era; based on fo ...

specimens (BRSMG Cb3869, BRSMG Cb3870, BRSMG Cb4063 and BRSUG 7007) discovered from the

Late Triassic The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch a ...

(

Rhaetian The Rhaetian is the latest age (geology), age of the Triassic period (geology), Period (in geochronology) or the uppermost stage (stratigraphy), stage of the Triassic system (stratigraphy), System (in chronostratigraphy). It was preceded by the N ...

)

Westbury Formation The Westbury Formation is a geological Formation (geology), formation in England, one of the Penarth Group. It dates back to the Rhaetian.Weishampel, David B; et al. (2004). "Dinosaur distribution (Late Triassic, Europe)." In: Weishampel, David B. ...

at the Aust Cliff. "Aust Colossus" has been tentatively estimated to be even larger than the long ichthyosaur ''

Ichthyotitan ''Ichthyotitan'' ( ) is an extinct genus of giant ichthyosaur from the Late Triassic (Rhaetian), known from the Westbury Formation, Westbury Mudstone Formation in Somerset, England. It is believed to be a shastasaurid, extending the family's ra ...

'' from the same formation, possibly over long, though the authors acknowledge that this is a very speculative estimate.

B

Batoremys

"Batoremys" is a genus of putative macrobaenid turtle from the Early Cretaceous of Mongolia. The intended type species "Batoremys leptis" was never given formal description, so it remains a ''nomen nudum''.

C

Clidastes moorevillensis

Clidastes ''Clidastes'' is an extinct genus of marine lizard belonging to the mosasaur family. It is classified as part of the Mosasaurinae subfamily, alongside genera like ''Mosasaurus'' and ''Prognathodon''. ''Clidastes'' is known from deposits ranging i ...

'' "moorevillensis" is an informal species of

mosasaur Mosasaurs (from Latin ''Mosa'' meaning the 'Meuse', and Ancient Greek, Greek ' meaning 'lizard') are an extinct group of large aquatic reptiles within the family Mosasauridae that lived during the Late Cretaceous. Their first fossil remains wer ...

from the Late Cretaceous

Mooreville Chalk Formation The Mooreville Chalk is a geological formation in North America, within the U.S. states of Alabama and Mississippi, which were part of the subcontinent of Appalachia. The strata date back to the early Santonian to the early Campanian stage of th ...

of Alabama. First named in a 1975 thesis, it was never given formal description and lacks sufficient diagnostic characters that differentiate it from the dubious ''Clidastes liodontus''.

Cuers ichthyosaur

The "Cuers ichthyosaur" is an informal name given to the giant

specimens (MHNTV PAL-1-10/2012 and MHNTV PAL-2/2010) discovered from the Late Triassic (

) locality in

Cuers Cuers () is a commune in the Var department in the Provence-Alpes-Côte d'Azur region in southeastern France. It has an aerodrome, Cuers-Pierrefeu Aerodrome, shared with nearby Pierrefeu. It was one of the locations of the 1995 Cuers massa ...

, France. It is suggested to be similar to the Autun ichthyosaur specimens (''Ichthyosaurus rheticus'' and ''Ichthyosaurus carinatus'', both of which are ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium,'' it may be impossible to determine whether a ...

'') and ''

''.

Cystosaurus

"Cystosaurus" is a genus of putative

teleosaur Teleosauridae is a family of extinct typically marine crocodylomorphs similar to the modern gharial that lived during the Jurassic period. Teleosaurids were thalattosuchians closely related to the fully aquatic metriorhynchoids, but were less ...

from France informally named by

Étienne Geoffroy Saint-Hilaire Étienne Geoffroy Saint-Hilaire (; 15 April 177219 June 1844) was a French naturalist who established the principle of "unity of composition". He was a colleague of Jean-Baptiste Lamarck and expanded and defended Lamarck's evolutionary theorie ...

in 1831. Because it was never given formal description, "Cystosaurus" remains a ''nomen nudum''. ''Cryptodraco'' was used as an unnecessary replacement name for '' Cryptosaurus'' by

Richard Lydekker Richard Lydekker (; 25 July 1849 – 16 April 1915) was a British naturalist, geologist and writer of numerous books on natural history. He was known for his contributions to zoology, paleontology, and biogeography. He worked extensively in cata ...

(1889) who believed the name ''Cryptosaurus'' was already previously in use for "Cystosaurus".

H

Hadongsuchus

"Hadongsuchus" (crocodile of

Hadong County Hadong County () is a county in South Gyeongsang Province, South Korea. It is located on the far-west side of the province, bordering South Jeolla Province. The county office is located at Hadeong-eup. History Hadong was originally called ''Dasach ...

) is an Early Cretaceous (

Aptian The Aptian is an age (geology), age in the geologic timescale or a stage (stratigraphy), stage in the stratigraphic column. It is a subdivision of the Early Cretaceous, Early or Lower Cretaceous epoch (geology), Epoch or series (stratigraphy), S ...

Albian The Albian is both an age (geology), age of the geologic timescale and a stage (stratigraphy), stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early Cretaceous, Early/Lower Cretaceous epoch (geology), Epoch/s ...

)

crocodyliform Crocodyliformes is a clade of Crurotarsi, crurotarsan archosaurs, the group often traditionally referred to as "crocodilians". They are the first members of Crocodylomorpha to possess many of the features that define later relatives. They are the ...

from the

Hasandong Formation The Hasandong Formation () is an Early Cretaceous (Aptian to Albian) geologic Formation (geology), formation in South Korea. It has been dated to the late Aptian and earliest Albian, between 118.0 ± 2.6 Ma and 112.4 ± 1.3 Ma. Dinosaur ...

of South Korea. Known from a long complete skull (KIGAM VP 200401) discovered in 2002, it was informally named as "Hadongsuchus acerdentis" in a 2005 thesis. Certain features of the third

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammals h ...

ry tooth help distinguish it from other related crocodylomorphs. Like other protosuchians, it is believed to have been a fully terrestrial cursorial animal with a semi-erect posture. Lee (2005) suggested that "Hadongsuchus" and three other crocodyliforms (''

Shantungosuchus ''Shantungosuchus'' is an extinct genus of Early Cretaceous crocodyliform found in China. It includes three species: ''Shantungosuchus chuhsienensis'' and ''S. brachycephalus'', which were both described by Yang Zhongjian – usually referre ...

'', ''

Sichuanosuchus ''Sichuanosuchus'' is an extinct genus of crocodyliform from the Late Jurassic and possibly Early Cretaceous of China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a populat ...

'', and ''

Zosuchus ''Zosuchus'' ("Zos anyoncrocodile") is a genus of basal, Late Cretaceous crocodyliform from Mongolia. The type species is ''Z. davidsoni'', after preparator Amy Davidson. The name was amended to ''davidsonae'' in 2004. Discovery It was found i ...

'') comprise a new family which represents a sister taxa to the Protosuchidae, with ''

'' being the closest relative.

Hainosaurus boubker

Hainosaurus ''Tylosaurus'' (; "knob lizard") is a genus of russellosaurine mosasaur (an extinct group of predatory marine lizards) that lived about 92 to 66 million years ago during the Turonian to Maastrichtian stages of the Late Cretaceous. Its fossils h ...

'' "boubker" is an informal species of

from the Sidi Chennane phosphate quarry in

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

. The description of ''H.'' "boubker" was published by a known predatory journal,

Scientific Research Publishing Scientific Research Publishing (SCIRP) is a predatory academic publisher of open-access electronic journals, conference proceedings, and scientific anthologies that are of questionable quality. , it offered 244 English-language open-access journ ...

, which places the validity of the publication and this taxon in questionable status. Some researchers provisionally considered ''H.'' "boubker" as a valid taxon.

Hitachinaka-ryu

"Hitachinaka-ryu" ( ヒタチナカリュウ) is the nickname give to single bone of fossil reptile (INM-4-15300) from

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

Maastrichtian The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (s ...

Nakaminato Group,

Ibaraki Prefecture is a Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Ibaraki Prefecture has a population of 2,828,086 (1 July 2023) and has a geographic area of . Ibaraki Prefecture borders Fukushima Prefecture to the north, ...

, Japan. It was originally identified as a right scapula of a

, but it is later re-identified as the right humerus of a trionychid turtle with estimated carapace length around . It has been renamed as "Hitachinaka-oosuppon" in 2021.

Hobetsu-araki-ryu

"Hobetsu-araki-ryu", or "Hoppy" is the nickname given to an

elasmosaurid Elasmosauridae, often called elasmosaurs or elasmosaurids, is an extinct family of plesiosaurs that lived from the Hauterivian stage of the Early Cretaceous to the Maastrichtian stage of the Late Cretaceous period (c. 130 to 66 mya). The taxo ...

(HMG 1) from early

Yezo Group The Yezo Group is a stratigraphic group in Hokkaido, Japan and Sakhalin, Russia which is primarily Late Cretaceous in age (Aptian to Earliest Paleocene). It is exposed as roughly north–south trending belt extending 1,500 kilometres through centr ...

Hokkaido is the list of islands of Japan by area, second-largest island of Japan and comprises the largest and northernmost prefectures of Japan, prefecture, making up its own list of regions of Japan, region. The Tsugaru Strait separates Hokkaidō fr ...

, Japan. It is known from a considerable number of postcranial materials, although not enough to identify at lower taxonomic levels.

I

Imrankhanuqab

"Imrankhanuqab" is an informal genus of

from the Vitakri Formation of Pakistan, described by M. Sadiq Malkani (2023) in

, a known predatory publisher. The proposed type species is "Imrankhanuqab qaeddiljani" and the proposed holotype GSP/Sangiali-1175 consists of a synsacrum, a pair of ilium, and several bones with cavities.

Induszalim

"Induszalim" is an informal genus of

named by M.S. Malkani based on fragmentary remains from the Vitakri Formation of Pakistan. The proposed type species, "Induszalim bala", was named in a 2014 conference abstract, rendering this name a ''nomen nudum''.

K

Kaosaurus

"Kaosaurus" is an informal genus of turtle from

Mt Indamane (Mont In Daman) site in

Niger Niger, officially the Republic of the Niger, is a landlocked country in West Africa. It is a unitary state Geography of Niger#Political geography, bordered by Libya to the Libya–Niger border, north-east, Chad to the Chad–Niger border, east ...

. It is described in Michaut (2002), but it is not considered as valid under ICZN rules. Michaut described a species of '' Stratodus'' ("S. indamanensis") and smaller relative "Ministratodus" from same site, which are also doubtful.

Khuzdarcroco

"Khuzdarcroco" is an informal genus of purported

mesoeucrocodylia Mesoeucrocodylia is the clade that includes Eusuchia and crocodyliforms formerly placed in the paraphyletic group Mesosuchia. The group appeared during the Early Jurassic, and continues to the present day. Diagnosis It was long known that Me ...

ns proposed by M.S. Malkani in a 2015

based on a rib fragment from the Goru Formation of Pakistan. The proposed type species is, "Khuzdarcroco zahri".

Kitadani goniopholidid

The "Kitadani goniopholidid", also called as "Tetori-wani" (テトリワニ, " Tetori crocodile") is a

goniopholidid Goniopholididae is an extinct family of moderate-sized semi-aquatic neosuchian crocodyliformes. Their bodyplan and morphology are convergent on living crocodilians. They lived across Laurasia (Asia, Europe and North America) between the Middle J ...

known from

Kitadani Formation The Kitadani Formation ( ''Kitadani-sō'') is a unit of Lower Cretaceous sedimentary rock which crops out near the city of Katsuyama in Fukui Prefecture, Japan, and it is the primary source of Cretaceous-aged non-marine vertebrate fossils in Jap ...

of Japan. Nearly complete skeleton was discovered in 1982, which is the first vertebrate record from Kitadani Dinosaur Quarry. Partial materials described in 2024 are likely to belong to the same taxon.

M

Macysuchus

"Macysuchus" is an informal genus of

phytosaur Phytosaurs (Φυτόσαυροι in Greek, meaning 'plant lizard') are an extinct group of large, mostly semiaquatic Late Triassic archosauriform or basal archosaurian reptiles. Phytosaurs belong to the order Phytosauria and are sometimes ref ...

from the Late Triassic

Cooper Canyon Formation The Cooper Canyon Formation is a geological formation of Norian age in Texas. It is one of several formations encompassed by the Dockum Group.Weishampel, David B; et al. (2004).Dinosaur distribution (Late Triassic, North America)" In: Weishampel, ...

, Texas, including single proposed species, "Macysuchus brevirostris". It is described in unpublished thesis after articulated specimen include skull and postcranial skeleton (TTUP 9425). This specimen is later referred to ''

Redondasaurus ''Redondasaurus'' is an extinct genus or subgenus of phytosaur from the Late Triassic (late Norian or Rhaetian) of the southwestern United States. It was named by Hunt & Lucas in 1993, and contains two species, ''R. gregorii'' and ''R. bermani''. ...

gregorii'' by Spielmann and Lucas (2012).

Marichimaera

"Marichimaera waiparaensis" (meaning

chimaera Chimaeras are Chondrichthyes, cartilaginous fish in the order (biology), order Chimaeriformes (), known informally as ghost sharks, rat fish (not to be confused with rattails), spookfish, or rabbit fish; the last two names are also applied to B ...

of the sea) is a ''nomen ex dissertationae'' created by Hallie Pritchett Street in their PhD thesis centered on the taxonomy of ''

''. It was given this name because the

(CM Zfr-108) apparently bore a mix of traits that were similar to the genera ''Mosasaurus'' and ''

''. This new genus was erected to contain the previously named species '' Prognathodon waiparaensis''. In Street's

, "Marichimaera" was recovered as being just outside of

Mosasaurini Mosasaurini is an extinct tribe of mosasaurine mosasaurs who lived during the Late Cretaceous and whose fossils have been found in North America, South America, Europe, Africa and Oceania, with questionable occurrences in Asia. They are highly d ...

. The type specimen was discovered in the Ladimore Formation from the

Mithasaraikistan

"Mithasaraikistan" is an informal genus of

named by M.S. Malkani (2021) in

, a known

predatory publisher Predatory publishing, also write-only publishing or deceptive publishing, is an exploitative academic publishing business model, where the journal or publisher prioritizes self-interest at the expense of scholarship. It is characterized by misle ...

. The known material of the intended type species "Mithasaraikistan ikniazi" consists of the proposed holotype snout (GSP/MSM-4-3) and the dentary ramus (GSP/MSM-139-3) from the Vitakri Formation of Pakistan.

Moanasaurus hobetsuensis

"Moanasaurus hobetsuensis" is a ''nomen ex dissertationae'' created by Hallie Pritchett Street in their PhD thesis centered on the taxonomy of ''

''. It is a combination of the existing

'' Moanasaurus'' (which currently contains only one valid species, ''M. mangahouangae'') and the previously named species ''Mosasaurus hobetsuensis'', which was named in 1985. Street's

recovered this specimen (HMG 12) as being within the ''Moanasaurus'' genus but as being distinct from the

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

by the saddle-shape of the glenoid condyle of the

humerus The humerus (; : humeri) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius (bone), radius and ulna, and consists of three sections. The humeral upper extrem ...

and other features of the vertebrae and

radius bone The radius or radial bone (: radii or radiuses) is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The ulna is longer ...

. The only known remains of "M. hobetsuensis" were discovered in the Hakobuchi Group on the island of

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

Moanasaurus longirostris

'' Moanasaurus'' "longirostris" is a ''nomen ex dissertationae'' created by Hallie Pritchett Street in their PhD thesis centered on the taxonomy of ''

''. The species was named as a new species of the existing

''Moanasaurus'' (which currently contains only one valid species, ''M. mangahouangae''). The

is IRSNB 3211, which was discovered in

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

, although the exact locality is not named. ''M''. "longirostris" differs from ''M. mangahouangae'' and "M. hobetsuensis" (section above) in the morphology of the zygapophyses and the

quadrate bone The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids ( reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms up ...

Monster of Aramberri

The " Monster of Aramberri", also known as the "Aramberri pliosaur", is an informal name given to a large pliosaur specimen (UANL-FCT-R2) discovered from the

Late Jurassic The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen ...

(

Kimmeridgian In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 154.8 ±0.8 Ma and 149.2 ±0.7 Ma (million years ago). The Kimmeridgian follows the Oxfordian ...

) La Caja Formation, Mexico. The body length of the "Aramberri pliosaur" is estimated around .

Mosasaurus glycys

''Mosasaurus'' "glycys" is a ''nomen ex dissertationae'' created by Hallie Pritchett Street in their PhD thesis centered on the taxonomy of ''

''. This new species was erected based on the specimen IRSNB R12, which was discovered in

, although the precise locality from which it was discovered is not known. It was distinguished from all the existing species of ''Mosasaurus'' based on the presence of more teeth in all of the tooth-bearing bones (

maxilla In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxil ...

e, dentaries, and

pterygoid Pterygoid, from the Greek for 'winglike', may refer to: * Pterygoid bone, a bone of the palate of many vertebrates * Pterygoid processes of the sphenoid bone ** Lateral pterygoid plate ** Medial pterygoid plate * Lateral pterygoid muscle * Medial ...

s) than ''Mosasaurus hoffmannii'' but fewer pterygoid and maxillary teeth than ''Mosasaurus lemonnieri''. It also possesses unique morphology of its

jugal bone The jugal is a skull bone found in most reptiles, amphibians and birds. In mammals, the jugal is often called the malar or zygomatic bone, zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by spe ...

, unlike any other species of ''Mosasaurus''. The species epithet "glycys" means "sweet", which is a reference to Belgium's reputation for chocolate production. The skull is similar in size to the holotype of ''Mosasaurus hoffmannii'', measuring about long, and it has been suggested that this specimen is a juvenile.

N

Nakagawa-kubinagaryu

Nakagawa-kubinagaryu (ナカガワクビナガリュウ, "Nakagawa plesiosaur") is the nickname given to an elasmosaurid plesiosaur (NMV 2) from deposit of Maastrichtian

in Nakagawa, Hokkaido. It is known from fragmentary skull and partial postcranial materials, which shares characters with '' Morenosaurus''. Direct comparison with '' Futabasaurus'' is difficult due to poor preservation, though ''Futabasaurus'' does not have a massive humerus which is present in both ''Morenosaurus'' and NMV 2.

Narynsuchus

"Narynsuchus" is an extinct

. Because it has never been formally described, it is currently considered a ''

nomen nudum In Taxonomy (biology), taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published ...

''. The name was first used in 1990 for fossil material found from a formation called the Balabansai Svita, which forms a

lens A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...

in site FTA-30 of the Sarykamyshsai 1 locality in the

Fergana Valley The Fergana Valley (also commonly spelled the Ferghana Valley) in Central Asia crosses eastern Uzbekistan, southern Kyrgyzstan and northern Tajikistan. Encompassing three former Republics of the Soviet Union, Soviet republics, the valley is e ...

Kyrgyzstan Kyrgyzstan, officially the Kyrgyz Republic, is a landlocked country in Central Asia lying in the Tian Shan and Pamir Mountains, Pamir mountain ranges. Bishkek is the Capital city, capital and List of cities in Kyrgyzstan, largest city. Kyrgyz ...

. The formation dates back to the

Callovian In the geologic timescale, the Callovian is an age and stage in the Middle Jurassic, lasting between 165.3 ± 1.1 Ma (million years ago) and 161.5 ± 1.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the ...

stage of the

Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...

. The known material of the intended

"Narynsuchus ferganensis" consists of large and characteristically striated teeth as well as a robust left

tibia The tibia (; : tibiae or tibias), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two Leg bones, bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outsi ...

. "Narynsuchus" is thought to have been larger than ''

Sunosuchus ''Sunosuchus'' is an extinct genus of goniopholidid mesoeucrocodylian. Fossils are known from China, Kyrgyzstan, and Thailand and are Jurassic in age, although some may be Early Cretaceous. Four species are currently assigned to the genus: the t ...

'', another

from Sarykamyshsai 1, due to the greater size of the known elements belonging to the genus. This material was first recognized as belonging to a new crocodyliform in 1989, when it was referred to as an indeterminate species of '' Peipehsuchus''.

O

Oolithorhynchus

"Oolithorhynchus" is an informal genus of

based on numerous humeri referred to '' Rhamphocephalus'' from the

(

Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...

) Eyford Member of the Fuller's Earth Formation. Because the paper proposing "Oolithorhynchus" was not formally published, this name is a ''nomen manuscriptum''.

P

Parirau

"Parirau" is an informal genus of

from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

(

) Maungataniwha Member of the Tahora Formation, New Zealand. The intended type species "Parirau ataroa" is named based on a single left ulna (NZMS CD 467) in a 2019 preprint, which renders this name a ''nomen nudum''. Originally described as an indeterminate pterosaur with possible similarities to '' Santanadactylus'' in a 1988 paper, NZMS CD 467 is classified as an indeterminate

azhdarchid Azhdarchidae (from the Persian word , , a dragon-like creature in Persian mythology) is a family of pterosaurs known primarily from the Late Cretaceous Period, though an isolated vertebra apparently from an azhdarchid is known from the Early Cre ...

in formal literature, contrary to the 2019 preprint which placed it within

Lonchodectidae Lonchodectidae or LonchodraconidaePêgas, R.V., Holgado, B., Leal, M.E.C., 2019. "''Targaryendraco wiedenrothi'' gen. nov. (Pterodactyloidea, Pteranodontoidea, Lanceodontia) and recognition of a new cosmopolitan lineage of Cretaceous toothed pter ...

Platychelone

"Platychelone" is an informal genus of

sea turtle Sea turtles (superfamily Chelonioidea), sometimes called marine turtles, are reptiles of the order Testudines and of the suborder Cryptodira. The seven existing species of sea turtles are the flatback, green, hawksbill, leatherback, loggerh ...

from the

type area of Netherlands. Named by

Louis Dollo Louis Antoine Marie Joseph Dollo (; 7 December 1857 – 19 April 1931) was a Belgian palaeontologist, known for his work on dinosaurs. He also posited that evolution is not reversible, known as Dollo's law. Together with the Austrian Othenio Ab ...

in 1909, the intended type species "Platychelone emarginata" is considered a ''nomen nudum'' as the taxon was based on an undescribed, large carapace with no illustrations.

Pricesaurus

"Pricesaurus megalodon" ("

Llewellyn Ivor Price Llewellyn Ivor Price (October 9, 1905 – June 9, 1980) was one of the first Brazilian paleontologists. His work contributed not only to the development of Brazilian but also to global paleontology. He collected ''Staurikosaurus'' in 1936, th ...

lizard") is a ''nomen nudum'' based on remains currently assigned to '' Anhanguera''. The remains were first brought up in a lecture by Rafael Gioia Martins-Neto in 1986. He notes several distinct features, but further research proved that all noted features are non-diagnostic and the taxon was ruled invalid due to improper naming conventions.

Procoelosaurus

"Procoelosaurus" is an informal genus of purported pterosauromorph from the Late Triassic

of Texas. Named in a 2002 thesis, the intended type species "Procoelosaurus brevicollis" was classified as an

ornithodira Avemetatarsalia (meaning "bird metatarsals") is a clade of diapsid reptiles containing all archosaurs more closely related to birds than to crocodilians. The two most successful groups of avemetatarsalians were the dinosaurs and pterosaurs. Di ...

n close to pterosaurs based on its hindlimb morphology. Other potential specimens identified as cf. "Procoelosaurus" were noted in a 2008 thesis. In 2012, this taxon was informally referred to as "procoelous vertebrate taxon A".

Pteromimus

"Pteromimus" is an informal genus of purported pterosauromorph from the Late Triassic

of Texas. Named in a 2002 thesis, the intended type species "Pteromimus longicollis" was classified as an

n close to pterosaurs based on its hindlimb morphology. A cervical vertebra identified as cf. "Pteromimus" was noted in a 2008 thesis. In 2012, this taxon was informally referred to as "procoelous vertebrate taxon B".

R

Raptocleidus

"Raptocleidus" is a

from the

Early Jurassic The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic� ...

(

Pliensbachian The Pliensbachian is an age of the geologic timescale and stage in the stratigraphic column. It is part of the Early or Lower Jurassic Epoch or Series and spans the time between 192.9 ±0.3 Ma and 184.2 ±0.3 Ma (million years ago). The Plie ...

) deposits of

Lyme Regis Lyme Regis ( ) is a town in west Dorset, England, west of Dorchester, Dorset, Dorchester and east of Exeter. Sometimes dubbed the "Pearl of Dorset", it lies by the English Channel at the Dorset–Devon border. It has noted fossils in cliffs and ...

, southern

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

. The genus contained two species, "Raptocleidus blakei" (LEICT G1.2002, one of the "Blockley plesiosaur" specimens) and "Raptocleidus bondi" (NHMUK R16330), both of which were informally named in a 2012 thesis. In the same thesis, the other two "Blockley plesiosaur" specimens (BHI 126445 and GLRCM specimen) and the other plesiosaur specimen from Dorset (BRSMG Ce17972a-o) are classified as "Raptocleidus" sp. It was likely a small plesiosaur, with an estimated body length of .

Rhamphodactylus

"Rhamphodactylus" is a nickname given to fossils of what is likely a basally-branching

pterodactyloid Pterodactyloidea ( ; derived from the Greek words ''πτερόν'' (''pterón'', for usual ''ptéryx'') "wing", and ''δάκτυλος'' (''dáktylos'') "finger") is one of the two traditional suborders of pterosaurs ("wing lizards"), and contai ...

from the

Mörnsheim Formation The Mörnsheim Formation is a geologic formation in Germany, near Daiting and Mörnsheim, Bavaria. It preserves fossils dating back to the Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigra ...

by Oliver Rauhut in 2012. The name references the mosaic of features that seem to recall both

Rhamphorhynchoidea The Rhamphorhynchoidea forms one of the two suborders of pterosaurs and represents an evolutionary grade of primitive members of flying reptiles. This suborder is paraphyletic unlike the Pterodactyloidea, which arose from within the Rhamphorhync ...

and

Pterodactyloidea Pterodactyloidea ( ; derived from the Greek words ''πτερόν'' (''pterón'', for usual ''ptéryx'') "wing", and ''δάκτυλος'' (''dáktylos'') "finger") is one of the two traditional suborders of pterosaurs ("wing lizards"), and contai ...

. The preserved skull bones are especially similar to ''

Pterodactylus ''Pterodactylus'' (from ) is a genus of extinct pterosaurs. It is thought to contain only a single species, ''Pterodactylus antiquus'', which was the first pterosaur to be named and identified as a flying reptile and one of the first prehis ...

'', the tail is similar to rhamphorhynchoids but also ''

Darwinopterus ''Darwinopterus'' (meaning "Darwin's wing") is a genus of pterosaur, discovered in China and named after biologist Charles Darwin. Between 30 and 40 fossil specimens have been identified, all collected from the Tiaojishan Formation, which dates t ...

'', the shoulder and arm bones are similar to ''

Rhamphorhynchus ''Rhamphorhynchus'' (, from Ancient Greek ''rhamphos'' meaning "beak" and ''rhynchus'' meaning "snout") is a genus of long-tailed pterosaurs in the Jurassic period. Less specialized than contemporary, short-tailed pterodactyloid pterosaurs such ...

'', and the metacarpal is almost exactly intermediate the two major clades. While the fossil material has been recognized as likely belonging to a new taxon, a proper

description Description is any type of communication that aims to make vivid a place, object, person, group, or other physical entity. It is one of four rhetorical modes (also known as ''modes of discourse''), along with exposition, argumentation, and narr ...

has not been published. Some publications have used the nickname "Rhamphodactylus" in reference to this important fossil, even including it in

phylogenetic analyses In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as Computational phylogenetics, phylogenetic inference. It infers the relationship among organ ...

, which have recovered it as a basal pterodactyloid within

Monofenestrata Monofenestrata is a clade of pterosaurs. It includes the pterosaurs in which the nasal and antorbital fenestra (openings/holes) in the skull are merged into a single fenestra. The clade includes the pterodactyloids and their close relatives. C ...

. A similar fossil, also with mosaic "transitional" features is discovered from the Painten Formation of Germany, which is now known as ''

Propterodactylus ''Propterodactylus'' (meaning "before ''Pterodactylus''") is an extinct genus of Transitional fossil, transitional monofenestratan pterosaurs from the Late Jurassic Painten Formation of Germany. The genus contains a Monotypic taxon, single specie ...

''.

Richmond pliosaur

The "Richmond pliosaur", also known as "Penny", is an informal name given to a complete

polycotylid Polycotylidae is a family of plesiosaurs from the Cretaceous, a sister group to Leptocleididae. They are known as false pliosaurs. Polycotylids first appeared during the Albian stage of the Early Cretaceous, before becoming abundant and widesprea ...

specimen (QM F18041) from the Early Cretaceous (

) Allaru Formation, Australia. Discovered in October 1989, this complete articulated specimen is measured around long. Within the family Polycotylidae, it is classified as a member of the clade Occultonectia, which also includes ''

Plesiopleurodon ''Plesiopleurodon'' (/ˌpliːsiəˈplʊərədɒn/; , meaning “near to”, ''pleuro'', meaning “side”, and ''don'', meaning “tooth”) is an extinct genus of Mesozoic marine reptiles, belonging to the Sauropterygia, known from the Late Cre ...

'' and '' Sulcusuchus''.

S

Satsuma-mukashi-umigame

"Satsuma-mukashi-umigame" ( サツマムカシウミガメ, "Satsuma (old name of Kagoshima) ancient sea turtle" is the nickname given to presumed chelonioidean sea turtle from

Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...

Goshoura Group, Shishijima Island,

Kagoshima Prefecture is a Prefectures of Japan, prefecture of Japan located on the island of Kyushu and the Ryukyu Islands. Kagoshima Prefecture has a population of 1,527,019 (1 February 2025) and has a geographic area of 9,187 Square kilometre, km2 (3,547 Square m ...

in Japan. Known from partial plastron and single cervical vertebra which shares characters with modern cheloniids, '' Corsochelys'' and ''

Toxochelys ''Toxochelys'' () is an extinct genus of marine turtle from the Late Cretaceous period. It is the most commonly found fossilized turtle species in the Smoky Hill Chalk, in western Kansas. Description ''Toxochelys'' had carapace about in leng ...

'', it is the oldest known marine turtle fossil from Japan. Carapace length is estimated to be around long.

Satsuma-utsunomiya-ryu

"Satsuma-utsunomiya-ryu" ( サツマウツノミヤリュウ) is the nickname given to an

from Cenomanian Goshoura Group, Shishijima Island, Kagoshima Prefecture in Japan. It is the oldest known elasmosaurid from East Asia, dating back to approximately 100 million years ago. The known material includes the

mandible In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone i ...

hyoid The hyoid-bone (lingual-bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid-cartilage. At rest, it lies between the base of the mandible and the third cervical verte ...

, fragments of the

skull The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate. In the human, the skull comprises two prominent ...

, 40

cervical vertebrae In tetrapods, cervical vertebrae (: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae. In saurop ...

, and a limb bone, possibly belonging to a juvenile individual. Features of the tooth surface ornamentation cervical vertebrae, suggest Satsuma-unomiya-ryu may represent a new species. The name references the former province name of the discovery site and the discoverer, Satoshi Utsunomiya. In 2021, Ustunomiya and Yasuhisa Nakajima reported the presence of a regurgitated " pellet" around its throat region.

Satsuma-yokuryu

"Satsuma-yokuryu" ( 薩摩翼竜, "Satsuma pterosaur") is a nickname given to fossil of partial limb bone of

described from Cenomanian Goshoura Group, Shishijima Island, Kagoshima Prefecture in Japan. This specimen was first discovered by Satoshi Utsunomiya during a TV program, he and Yasuhisa Nakajima analyzed material and found to be a part of limb bone. Its wingspan would be around .

Sinuiju pterosaur

The "Sinuiju pterosaur" is an informal name given to the

anurognathid Anurognathidae is a family (biology), family of small, short-tailed pterosaurs that lived in Europe, Asia, and possibly North America during the Jurassic and Cretaceous periods. Eight genera are definitively known: ''Anurognathus'', from the Late ...

specimen (CKGP 19960828, formerly PS198922) discovered from the Sinuiju Formation of North Korea. This specimen has been tentatively assigned to ''

Jeholopterus ''Jeholopterus'' was a small anurognathid pterosaur known from the Middle to Late Jurassic Daohugou Beds of the Tiaojishan Formation of Inner Mongolia, China, and possibly the Early Cretaceous Sinuiju Formation of North Korea. Naming The gen ...

'' cf. ''ningchengensis'', and another pterosaur specimen (PS199921) is also known from the same formation.

Speeton Clay plesiosaurian

The "Speeton Clay plesiosaurian" is an informal name given to the

specimens (NHMUK PV R8623 and SCARB 200751) from the Early Cretaceous (

Hauterivian The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous Epoch or a stage in the Lower Cretaceous Series. It spans the time between 132.6 ± 2 Ma and 125.77 (million years ago). The Hauterivian is preceded by the Valangi ...

)

Speeton Clay Formation The Speeton Clay Formation (SpC)Speeton Clay Formation
- metriorhynchid Metriorhynchidae is an extinct family of specialized, aquatic metriorhynchoid crocodyliforms from the Middle Jurassic to the Early Cretaceous period (Bajocian to early Aptian) of Europe, North America and South America. The name Metriorhynchidae ...

mandible specimen (MGP-PD 26552) from the Late Jurassic (possibly Oxfordian) of northern Italy. Estimated around in total body length, Andrea Cau tentatively referred this specimen to '' Neptunidraco'', but other researchers argued that it likely belongs to a separate, indeterminate metriorhynchid.

Stereosaurus

"Stereosaurus" is a

from the

Cambridge Greensand The Cambridge Greensand is a geological unit in England whose strata are earliest Cenomanian in age. It lies above the erosive contact between the Gault Formation and the Chalk Group in the vicinity of Cambridgeshire, and technically forms the l ...

(

). The genus contains three species, "Stereosaurus platyomus", "S. cratynotus" and "S. stenomus", all of which were informally coined in 1869 by British

paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

Harry Seeley Harry Govier Seeley (18 February 1839 – 8 January 1909) was a British paleontologist. Early life Seeley was born in London on 18 February 1839, the second son of Richard Hovill Seeley, a goldsmith, and his second wife Mary Govier. When his fa ...

, who considered them to be plesiosaurian.Seeley, H.G. (1869). ''Index to the fossil remains of Aves, Ornithosauria and Reptilia, from the Secondary system of strata arranged in the Woodwardian Museum of the University of Cambridge''. Cambridge, 143 pp.

Sulaimanisuchus

"Sulaimanisuchus" is an informal genus of purported mesoeucrocodylians from the Cretaceous Vitakri Formation of Pakistan, mentioned by M. Sadiq Malkani in 2010. The proposed holotype is a partial mandibular symphysis. The intended type species is "Sulaimanisuchus kinwai."

T

Tylosaurus borealis

Tylosaurus ''Tylosaurus'' (; "knob lizard") is a genus of Russellosaurina, russellosaurine mosasaur (an extinct group of predatory marine Squamata, lizards) that lived about 92 to 66 million years ago during the Turonian to Maastrichtian stages of the Late ...

'' "borealis" is an informal species of

, with the known specimen discovered from approximately northeast of

Grande Prairie Grande Prairie is a city in Northern Alberta, northwestern Alberta, Canada, within the southern portion of an area known as Peace River Country. It is located at the intersection of Alberta Highway 43, Highway 43 (part of the CANAMEX Corridor) ...

. It was named in a 2020 thesis by Samuel Garvey who described a partial skull of ''Tylosaurus'' catalogued as

TMP TMP may refer to: Arts and media * Tickle Me Pink, a rock band from Colorado, US (2005–2011) * Tiny Moving Parts, an emo band from Minnesota, US * Tom Malone Prize, an Australian glass art prize * Tsukuyomi -Moon Phase-, a 2000–2008 anime ...

2014.011.0001, which makes the specimen the northernmost known occurrence of this genus.

U

Umikosaurus

"Umikosaurus" (meaning lizard child of the sea) is a ''nomen ex dissertationae'' created by Hallie Pritchett Street in their PhD thesis centered on the taxonomy of ''

''. It was named to contain the existing species ''Mosasaurus prismaticus'', which was named by K. Sakurari and colleagues in 1999. Street's

did not recover ''M. prismaticus'' within a

''Mosasaurus'' genus, but rather found that "Umikosaurus" was a close relative of ''

'' and ''Mosasaurus conodon'' (which they renamed " Aktisaurus conodon"), which is reflected in the morphology of the carinae on its teeth. The

, HMG 1065, was discovered in the Hakobuchi Group on the island of

W

Wadanaang

"Wadanaang" is an informal genus of madtsoiid snake named by M.S. Malkani (2021) in

, a known

. The known material of the intended type species "Wadanaang kohsulaimani" consists of fragmentary teeth and vertebra from the Vitakri Formation of Pakistan.

Wyomingopteryx

The name "Wyomingopteryx" appears in a painting of Morrison prehistoric animals by

Robert Bakker Robert Thomas Bakker (born March 24, 1945) is an American paleontologist who helped reshape modern theories about dinosaurs, particularly by adding support to the theory that some dinosaurs were endothermic (warm-blooded). Along with his mentor ...

. However, this binomen is a ''

'', and it is possible that Bakker may have intended to coin "Wyomingopteryx" for the ''Istiodactylus''-like specimen TATE 5999 because that specimen is found in Wyoming.Bakker, R.T. (1998). "Dinosaur mid-life crisis: the Jurassic-Cretaceous transition in Wyoming and Colorado". In Lucas, Spencer G.; Kirkland, James I.; Estep, J.W. Lower and Middle Cretaceous Terrestrial Ecosystems 14. New Mexico Museum of Natural History and Science Bulletin. pp. 67–77.

Z

Zahrisaurus

"Zahrisaurus" is an informal genus of purported plesiosaurs from the ?Jurassic Sulaiman Group of

Balochistan Balochistan ( ; , ), also spelled as Baluchistan or Baluchestan, is a historical region in West and South Asia, located in the Iranian plateau's far southeast and bordering the Indian Plate and the Arabian Sea coastline. This arid region o ...

, described by M. Sadiq Malkani (2019) in

, a known

. The proposed holotype is allegedly a portion of the trunk with associated ribs. The intended type species is "Zahrisaurus kilmoolai."

References

{{Reflist Lists of prehistoric reptiles Lists of prehistoric animal genera (alphabetic) Mesozoic reptiles Nomina nuda

A

Addyman plesiosaur

African pterosaur

Aktisaurus

Amblyrhynchosaurus

Antipodenectes

Aust Colossus

B

Batoremys

C

Clidastes moorevillensis

Cuers ichthyosaur

Cystosaurus

H

Hadongsuchus

Hainosaurus boubker

Hitachinaka-ryu

Hobetsu-araki-ryu

I

Imrankhanuqab

Induszalim

K

Kaosaurus

Khuzdarcroco

Kitadani goniopholidid

M

Macysuchus

Marichimaera

Mithasaraikistan

Moanasaurus hobetsuensis

Moanasaurus longirostris

Monster of Aramberri

Mosasaurus glycys

N

Nakagawa-kubinagaryu

Narynsuchus

O

Oolithorhynchus

P

Parirau

Platychelone

Pricesaurus

Procoelosaurus

Pteromimus

R

Raptocleidus

Rhamphodactylus

Richmond pliosaur

S

Satsuma-mukashi-umigame

Satsuma-utsunomiya-ryu

Satsuma-yokuryu

Sinuiju pterosaur

Speeton Clay plesiosaurian

Stereosaurus

Sulaimanisuchus

T

Tylosaurus borealis

U

Umikosaurus

W

Wadanaang

Wyomingopteryx

Z

Zahrisaurus

See also

References