List of informally named dinosaurs
This list of informally named dinosaurs is a listing of dinosaurs that have never been given formally published scientific names. This list only includes names that were not properly published and have not since been published under a valid name. The following types of names are present on this list:
- Nomen nudum, Latin for "naked name": A name that has appeared in print but has not yet been formally published by the standards of the International Commission on Zoological Nomenclature. Nomina nuda 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.
- Nicknames or descriptive names given to specimens or taxa by researchers or the press.
A
Airakoraptor
"Airakoraptor" is an informal name given to a genus of dromaeosaurian theropod from the Upper Cretaceous of Mongolia. The nomen nudum was accidentally created by Perle et al. in their 1992 in a citation for a paper called "Morphology Dromaeosaurian dinosaur-Airakoraptor from the upper cretaceous of Mongolia". As the journal and volume of the listed paper contain no such publication, the actual title for the work likely being "New dromaeosaur material from the Late Cretaceous of Mongolia" by the same authors as listed, there is no verifiable publication for this taxon name. The proper publication described three specimens, one of which is not referred to by a specimen number, and most likely corresponds to the material "Airakoraptor" was to be named for. This specimen, IGM 100/981, was found in Khulsan and is referrable to Dromaeosauridae while likely distinct from Velociraptor.Amargastegos
"Amargastegos" is an informally named genus of extinct stegosaurid ornithischian dinosaur known from the La Amarga Formation of Argentina on the basis of MACN N-43. In 2016, Peter Malcolm Galton and Kenneth Carpenter declared it a nomen dubium, establishing it as an indeterminate stegosaur.Andhrasaurus
"Andhrasaurus indicus" is an informal genus of extinct armored ornithischian dinosaur from the Kota Formation of India. Ulansky coined the name for skull elements, about 30 osteoderms, and the extremities of vertebrae and limbs, all preserved in the collections of the GSI and assigned to Ankylosauria by Nath et al.. In 2016, Peter Malcolm Galton and Kenneth Carpenter noted that "Andhrasaurus" did not meet ICZN requirements and therefore declared it a nomen nudum, listing it as Thyreophora indet., while noting that the jawbones described by Nath et al. belonging to crocodylomorphs. The dermal armor informally named "Andhrasaurus" was redescribed by Galton.Angeac ornithomimosaur
The "Angeac ornthomimosaur" is an informal name given to an unnamed orthithomimosaur taxon known from an Early Cretaceous bone bed near Angeac in France. The taxon is toothless and is known from multiple individuals collectively covering much of the skeleton, some remains were described by Allain et al.Angloposeidon
"Angloposeidon" is the informal name given to a sauropod dinosaur from the Early Cretaceous Wessex Formation of the Isle of Wight in southern England. It was a possible brachiosaurid but has not been formally named. Darren Naish, a notable vertebrate palaeontologist, has worked with the specimen and has recommended that this name only be used informally and that it not be published. However, he published it himself in his book Tetrapod Zoology Book One from 2010. The remains consist of a single cervical vertebra, which indicate it was a very large animal, 20 metres or greater in length.Archaeoraptor
"Archaeoraptor" is the informal generic name for an important fossil from China that was later discovered to be a fake. The name was created in an article published in National Geographic magazine in 1999, where the magazine claimed that the fossil was a "missing link" between birds and terrestrial theropod dinosaurs. Even prior to this publication there had been severe doubts about the fossil's authenticity. Further scientific study showed it to be a forgery constructed from rearranged pieces of real fossils from different species. Zhou et al. found that the head and upper body actually belong to a specimen of the primitive fossil bird Yanornis, and another 2002 study found that the tail belongs to a small winged dromaeosaur, Microraptor, named in 2000. The legs and feet belong to an as yet unknown animal.Archbishop
"The Archbishop" is a giant brachiosaurid sauropod dinosaur similar to Brachiosaurus and Giraffatitan. It was long considered a specimen of Brachiosaurus brancai due to being found in the same formation in Tendaguru, Tanzania. However, the "Archbishop" shows significant differences including a unique vertebral morphology and a proportionally longer neck, that indicates it is a different, previously unknown genus and species. It was discovered by Frederick Migeod in 1930. "The Archbishop" is a nickname that functions as a placeholder – the specimen currently has no scientific name. The specimen is currently housed in the Natural History Museum in London, and will eventually be re-described by Dr. Michael P. Taylor of Bristol University. In May 2018, Taylor started to work on describing the Archbishop.B
Balochisaurus
"Balochisaurus" is an informal taxon of titanosaurian sauropod dinosaur from the Late Cretaceous of Pakistan. The proposed species is "B. malkani". The discovery was made near Vitariki by a team of paleontologists from the Geological Survey of Pakistan. Described in 2006 by M.S. Malkani, the genus is based on seven tail vertebrae found in the Maastrichtian-age Vitakri Member of the Pab Formation, with additional vertebrae and a partial skull assigned to it. Balochisaurus was assigned to the family "Balochisauridae" along with "Marisaurus", although the family was used as a synonym of older Saltasauridae.Barnes High Sauropod
The "Barnes High sauropod" is the informal name given to MIWG-BP001, an undescribed sauropod dinosaur specimen from the Wessex Formation on the Isle of Wight. It was discovered in the cliffs around Barnes High in 1992 and is currently owned by the privately run unaccredited Dinosaur Farm Museum near Brighstone, the ownership situation was described as "complex" and the specimen is currently inaccessible to researchers. It is roughly 40% complete and consists of a "Partial postcranial skeleton, including presacral vertebrae, anterior caudal vertebrae, girdle and limb elements" including a largely complete forelimb. It has been suggested to be a Brachiosaur and is possibly synonymous with the earlier named Eucamerotus due to similarities with the vertebrae.Bayosaurus
"Bayosaurus" is the informal name given to an as yet undescribed genus of dinosaur. The name was coined by paleontologists Rodolfo Coria, Philip J. Currie, and Paulina Carabajal in 2006. It apparently was an abelisauroid from the Turonian Cerro Lisandro Formation of Neuquén, Argentina, around long. The specimen is MCF-PVPH-237, including dorsal and sacral vertebrae, a fragmentary pelvis, and other partial bones. The name was used in a phylogenetic analysis to indicate the position of MCF-PVPH-237. The suggested binomial was "Bayosaurus pubica".Beelemodon
"Beelemodon" is the informal name given to an undescribed theropod genus from the Late Jurassic, possibly belonging to a coelurosaur. The fossils include two teeth found in Wyoming, United States. The name appeared in print in 1997, when paleontologist Robert T. Bakker mentioned it in a symposium for the Academy of Natural Sciences. The teeth are most similar to Compsognathus, but have no unique features and also share similarities with Protarchaeopteryx and dromaeosaurids.Bihariosaurus
"Bihariosaurus" is an invalid genus of iguanodontian dinosaur from Early Cretaceous Romania. The type species, "Bihariosaurus bauxiticus", was named but not described by Marinescu in 1989. It was similar to Camptosaurus, and was an iguanodont. The original publication of the taxon did not include sufficient description, and the illustrations cannot distinguish it from any other ornithopod.Biscoveosaurus
"Biscoveosaurus" is the informal name of an ornithopod dinosaur specimen from the Early Maastrichtian age Snow Hill Island Formation of James Ross Island, Antarctica. It comes from the Cape Lamb Member of the formation, the same member as Morrosaurus, another basal ornithopod. As such, it's been suggested it may be a secondary specimen of that species, but as the holotype of Morrosaurus is fragmentary and doesn't overlap with the material of "Biscoveosaurus", this can't as yet be tested. The specimen consists of dentaries, teeth, a braincase, parts of the maxillae, forelimb elements, assorted vertebrae, and the pectoral girdle; this makes it unique compared to the other James Ross Island ornithopods, which don't presever both cranial and postcranial remains. It has been estimated the animal would've been about in length.C
Capitalsaurus
"Capitalsaurus" is the informal genus name given to the species formerly known as Creosaurus potens and Dryptosaurus potens, a dinosaur from the Arundel Formation of North America. The only known specimen was discovered in Washington, D.C. It was a theropod, and it lived during the Cretaceous. It is a nomen nudum, the name having never been formally published. "Capitalsaurus" was discovered in January 1898 at the intersection of First and F Streets S.E., in the District of Columbia – an intersection now designated as Capitalsaurus Court. It was not uncovered by any paleontological activity, but as a by-product of sewer work. The only known specimen of "Capitalsaurus" consists of part of a single vertebra. Some paleontologists feel that this is insufficient justification for a name that suggests an entire genus, and that "Capitalsaurus" is merely an undetermined theropod. Others note that this is hardly the only dinosaur with a common name that does not helpfully reflect its taxonomy. The "Capitalsaurus" is the official dinosaur of the District of Columbia.Changdusaurus
"Changdusaurus" is the informal name given to a genus of dinosaur from the Late Jurassic Period. It lived in what is now China. "Changdusaurus" is classified as a stegosaurid. The type species was named "Changdusaurus laminoplacodus" by Zhao in 1986, but it has never been formally described, and remains a nomen nudum. One source indicates the fossils have been lost.Comanchesaurus
"Comanchesaurus" is an informal name for fossilized remains from the Late Triassic of New Mexico that were initially interpreted as belonging to a theropod dinosaur. The remains, NMMNH P-4569, consist of a partial skeleton including vertebral centra and hindlimb bones, and came from the Norian-age Upper Triassic Bull Canyon Formation of Guadalupe County. Adrian Hunt, in his unpublished dissertation, proposed the name "Comanchesaurus kuesi" for the specimen, but the name was never adopted, and was first referred to in the scientific literature in a 2007 redescription of Late Triassic North American material thought to belong to dinosaurs. In the redescription, the authors found the material to belong to a "possible indeterminate saurischian".D
Dachongosaurus
"Dachongosaurus" is the informal name given to an undescribed genus of sauropod dinosaur from the Early Jurassic of China. It is known from fossils including at least a partial articulated skeleton from the Dark Red Beds of the Lower Lufeng Series in Yunnan. Possibly a cetiosaur, the "type species" is "Dachongosaurus yunnanensis", coined by Zhao in 1985. An alternate spelling is "Dachungosaurus". As with other informal names coined by Zhao in 1985 and 1983, nothing has since been published, and the remains may have been redescribed under another name.Damalasaurus
"Damalasaurus" is the informal name given to a genus of herbivorous dinosaur from the Early Jurassic. It was a sauropod, though its exact classification within the clade is unknown. Fossils of "Damalasaurus", including a rib, have been found in the Middle Daye Group of Tibet. Species attributed to this genus include "Damalasaurus laticostalis" and "D. magnus".Duranteceratops
"Duranteceratops" is a purported new taxon of chasmosaurine ceratopsid from the Hell Creek Formation. In 2012, a ceratopsid skull reportedly distinguishable from Triceratops was unearthed in South Dakota by an amateur fossil hunter named John Carter. Though it has yet to be published, according to the Prehistoric Times issue no. 121 from Spring 2017, the specimen is to be named "Duranteceratops".E
EK troodontid
The "EK troodontid" is an unnamed genus of troodontid dinosaur discovered in Mongolia. In the scientific literature it is referred to as the "EK troodontid", after the Early Cretaceous sediments in which it was found. SPS 100/44 was discovered by S.M. Kurzanov during the 1979 Soviet-Mongolian Paleontological Expedition. It was found in deposits of the Barunbayaskaya Svita at the Khamareen Us locality, Dornogov, in the Mongolian People's Republic. SPS 100/44 was described by Rinchen Barsbold and colleagues in 1987.Its fossil remains include an incomplete skeleton consisting of the braincase, posterior parts of the lower mandibles, a maxillary fragment with teeth, parts of five cervical vertebrae, an articulated right manus with partial semilunate, left manus phalanx I-1, distal end of the left femur, and fragmentary left and right pedes. Barsbold pointed out that the specimen was smaller and from older sediments than other known troodontids, but it had some features of the skull that could have made it a juvenile. Barsbold also indicated the high degree of fusion of the bones of the skull and the unusual foot morphology to indicate that it might be an adult of an unknown taxon. Barsbold took the conservative position and did not name this specimen because it was not complete enough to rule out the possibility that it was a juvenile of a known genus of troodontid. Barsbold also noted that the naturally articulated manus of SPS 100/44 showed no signs of an opposable third digit, as was suggested for Troodon by Russell and Seguin in 1982. Turner and colleagues, in 2007, found the EK troodontid to be a distinct basal genus of troodontid, in a polytomy with Jinfengopteryx and a clade of more derived troodontids.
Eoplophysis
"Eoplophysis" is a genus of stegosaur known from the Middle Jurassic Cornbrash Formation, Sharp's Hill Formation, and Chipping Norton Formation of England. It was originally named Omosaurus vetustus by the renowned German paleontologist Friedrich von Huene. The holotype, OUM J.14000, is a right femur of a juvenile individual from the Middle Jurassic Cornbrash Formation of Oxfordshire, England, although it was probably reworked from the slightly older Forest Marble Formation in view of its eroded nature. Because of the renaming of Omosaurus, an occupied name, as Dacentrurus, O. vetustus was renamed into a Dacentrurus vetustus in 1964. In the 1980s, researcher Peter Malcolm Galton reviewed all known stegosaur material from the Bathonian of England and concluded that Omosaurus vetustus was valid and should be tentatively referred to Lexovisaurus. However, the species was later considered a nomen dubium in both reviews of Stegosauria. In their alpha-taxonomic review of stegosaurs, Susannah Maidment and her colleagues noted that OUM J.14000 shares characters present in both sauropods and stegosaurs, but that it lacks synapomorphies exclusive to Stegosauria and assigned it as a Dinosauria indet. Nevertheless, the amateur paleontologist Roman Ulansky coined the new genus "Eoplophysis" for O. vetustus, noting differences with the femora of other stegosaurs.Eugongbusaurus
"Eugongbusaurus" is the informal name proposed for a neornithischian found in the Oxfordian-age Shishugou Formation of Xinjiang, China. The intended type species, "Gongbusaurus" wucaiwanensis, was described by Dong Zhiming in 1989 for two partial skeletons as a second species of the poorly known tooth taxon Gongbusaurus. Fragmentary skeleton IVPP 8302, the type specimen for the new species, included a partial lower jaw, three tail vertebrae, and a partial forelimb. Second specimen IVPP 8303 consisted of two hip vertebrae, eight tail vertebrae, and two complete hind limbs. Dong estimated it as around long, and considered it to be a strong runner. He assigned the genus Gongbusaurus to the Hypsilophodontidae, a paraphyletic grade of small herbivorous bipedal dinosaurs. Because dinosaur teeth are generally not distinctive enough to hold a name, it is unsurprising that other paleontologists have suggested removing "G." wucaiwanensis from Gongbusaurus and giving it its own genus. The possible replacement name "Eugongbusaurus" leaked out accidentally and remains informal.F
Fendusaurus
Fendusaurus is a nomen ex dissertatione proposed by Fedak for FGM998GF13-II, which includes a skull. Other specimens referred to Fendusaurus are FGM998GF13-I, FGM998GF13-III, FGM998GF69, FGM998GF9, and FGM998GF18, all found by a crew from the Princeton University. All the specimens include femora and coracoids, and although they each share slightly different features, the differences are credited to intra-specific variation. Known specimens of Fendusaurus were previously classified as cf. Ammosaurus. The femora and coracoids also help identify different individuals, and Timothy J. Fedak, the described of the specimens, found that each block represented about one individual. Fendusaurus is known from the Early Jurassic McCoy Brook Formation of Wasson Bluff, Nova Scotia. As five specimens of Fendusaurus are from the McCoy Brook Formation, the formation is the richest prosauropod site in North America. The formation is also similar to other formations of North America and Asia, as it lacks any remains presently assigned to Anchisaurus. Fedak places Fendusaurus as a genus of the family Massospondylidae.The specimens of Fendusaurus include mostly crushed vertebrae, along with appendicular elements. They are distinguishable from Anchisaurus by the morphology of both the ilium and sacral vertebrae. However, in some specimens, the morphology of the femora and coracoids are quite different, which led Fedak to speculate that more than one species may have been present. Fendusaurus, according to Fedak, can be distinguished from all closely related sauropodomorphs by the extreme elongation of the cervical vertebrae; a four vertebrae sacrum that includes a dorsosacral and caudosacral; the elongate postacetabular process of the ilium; and an expanded anterior distal process of the tibia.
Ferganastegos
"Ferganastegos" is a dubious genus of stegosaur from the Middle Jurassic Balabansai Formation of Fergana Valley, Kyrgyzstan. The holotype of "Ferganastegos callovicus", IGB 001, consists of four posterior dorsal vertebrae. Although Averianov et al. did not consider the vertebrae diagnostic to genus, the freelance Russian dinosaur enthusiast and amateur paleontologist Roman Ulansky decided that the differences between IGB 001 and other stegosaurs were sufficient to warrant a binomial for IGB 001, "Ferganastegos callovicus", despite the fact he did not examine the material himself. Other researchers still contend that the material is not diagnostic and that the genus is a nomen dubium.Futabasaurus
"Futabasaurus" is an informal name for a genus of theropod dinosaur from the Late Cretaceous of Japan, known only from a partial shin bone discovered in the Coniacian-age Ashizawa Formation of the Futaba Group. It was coined by David Lambert in 1990 as a conversion from the Japanese nickname "Futaba-ryu", for an undescribed theropod. Dong Zhiming and coauthors briefly discussed the fossil shin bone it was based on that same year, publishing a photograph. They considered the bone to belong to an indeterminate tyrannosaurid. If the specimen is eventually described and named, it will require a different name, because the name Futabasaurus has since been used for a genus of plesiosaur.G
Gadolosaurus
"Gadolosaurus" is an informal name given to an undescribed hadrosauroid from the Bayan Shireh Formation of Baishan Tsav, Mongolia. The name "Gadolosaurus" was first used in a 1979 book by Japanese paleontologist Tsunemasa Saito, in a caption for a photo of a juvenile dinosaur skeleton. This small individual was only about a meter long. The skeleton was part of a Soviet exhibition of fossils in Japan. Apparently, the name comes from a Japanese phonetic translation of the Cyrillic word gadrosavr, or hadrosaur, and was never meant by the Russians to establish a new generic name.Despite being merely a mistranslation of gadrosavr, it appeared in many popular dinosaur books, with varying identifications. Donald F. Glut in 1982 reported it as either an iguanodont or hadrosaur, with no crest or boot on the ischium, and suggested it could be the juvenile of a previously named genus like Tanius or Shantungosaurus. David Lambert in 1983 classified it as an iguanodont, but changed his mind by 1990, when it was listed as a synonym of Arstanosaurus without comment. What may be the same animal is mentioned but not named by David B. Norman and Hans-Dieter Sues in a 2000 book on Mesozoic reptiles from Mongolia and the former USSR; this material, from the Soviet-Mongolian expeditions of the 1970s, had been listed as Arstanosaurus in the Russian Academy of Sciences, and was found in the Cenomanian-age Bayan Shireh Formation of Baishin Tsav.
Gallimimus mongoliensis
"Gallimimus mongoliensis" is an informal name Rinchen Barsbold used for a nearly complete skeleton, but since it differs from Gallimimus in some details, Yoshitsugu Kobayashi and Barsbold proposed in 2006 that it probably belongs to a different genus.Gspsaurus
"Gspsaurus" is a titanosaurian sauropod dinosaur from the Late Cretaceous Vitakri Formation of Sulaiman Basin of Pakistan. It has been suggested to be synonymous with the also invalid taxon "Maojandino", also proposed by Malkani.Grusimimus
"Grusimimus" is an informal name for an undescribed genus of ornithomimid from the Early Cretaceous aged Shinekhudag Formation of Mongolia. Known from a skeleton including all regions except the skull, "Grusimimus" was given an invalid name in 1997 by Rinchen Barsbold, who also suggested the species name "tsuru". The specimen was found in 1996 and examined by Barsbold before he suggested the informal name, a nomen nudum. An abstract and poster were presented on the taxon by Kobayashi & Barsbold in 2002, and the former published a thesis paper on the specimen which found the taxon to be close to Harpymimus phylogenetically but possible more derived.H
Hanwulosaurus
"Hanwulosaurus" is the informal name given to an as-yet undescribed genus of dinosaur from the Late Cretaceous. It was an ankylosaur around long, which is long for an ankylosaur. Its fossils were found in Inner Mongolia, China. Much of a skeleton, including a complete skull, vertebrae, ribs, a scapula, an ulna, femorae, bones from the shin, and armor, was discovered; this may be the most complete ankylosaurian skeleton yet found in Asia, according to early reports. Zhao Xijin, who has studied it, suggests that it may belong to its own subgroup within the Ankylosauria. The name first surfaced in news reports in 2001.Heilongjiangosaurus
"Heilongjiangosaurus" is the informal name given to an as-yet undescribed genus of duckbilled dinosaur from the Late Cretaceous. It possibly was a lambeosaurine, and may in fact be the same animal as Charonosaurus. The fossils were found in Maastrichtian-age rocks in Heilongjiang, China. As a nomen nudum, it is unclear what material it was intended to be based on, but might be connected to the nomen nudum "Mandschurosaurus" jiainensis, informally named in a 1983 publication.The "type species" is "H. jiayinensis", and it was coined in 2001 in a faunal list by Li and Jin.
Hironosaurus
"Hironosaurus" is the informal name given to an as-yet undescribed genus of dinosaur from the Late Cretaceous. Found in Hirono, Fukushima, Japan, it was probably a type of hadrosaur, although no subfamily identification has been made. The fossils are quite fragmentary, and consist of teeth and a vertebra, possibly from the tail. Since the fossils have never been fully described in a scientific paper, "Hironosaurus" is considered a nomen nudum. It was first mentioned by Hisa in an obscure 1988 publication and was later brought to a wider audience by David Lambert. Dong Zhiming, Y. Hasegawa, and Y. Azuma regarded the material as belonging to a hadrosaurid, but lacking any characteristics to allow more precise identification.Hisanohamasaurus
"Hisanohamasaurus" is the informal name given to an as yet undescribed genus of dinosaur from the Late Cretaceous. It is a nomen nudum known only from teeth that first appeared in a general-audience dinosaur book by David Lambert in 1990. Although initially identified a diplodocid, it later re-identified as a nemegtosaurid similar to Nemegtosaurus. As its name suggests, its fossils were found in Japan. The location is part of Iwaki, Fukushima.I
Ichabodcraniosaurus
"Ichabodcraniosaurus" is an informal name for theropod fossils were first discovered within the Gobi Desert in China. The remains consist of a partial skeleton without a head, from which its name refers to the fictional character Ichabod Crane, a character in the history of Washington Irving's The Legend of Sleepy Hollow, where he was pursued by a headless horseman. Fossils include a hyoid bone, cervical vertebrae, a supposed skull and a supposed jaw bone. "Ichabodcraniosaurus" was named by Novacek in 1996. This specimen may belong to Velociraptor mongoliensis, but Norell and Makovicky concluded that it was not complete enough to say for sure, and it awaits a formal description.J
Jiangjunmiaosaurus
"Jiangjunmiaosaurus" is an informal name created by an anonymous author in 1987 for a possible chimaera of Monolophosaurus and Sinraptor.Jindipelta
"Jindipelta" is the currently informal name given to an ankylosaur from the Zhumapu Formation in China. It is known from a partial skeleton found in Cenomanian rocks. The name was first announced in the 2019 SVP abstract book, alongside the megalosauroid Yunyangosaurus.Julieraptor
"Julieraptor" is the nickname of a dromaeosaurid fossil found in the Judith River Formation, Montana in 2002. Parts of the same skeleton were illegally excavated and nickamed Sid Vicious in 2006, and the excavator subsequently served jail time for the theft. Bob Bakker therefore also nicknamed the specimen "Kleptoraptor". The skeleton was arranged to be sold to Royal Ontario Museum. It is known from a skeleton consisting of an almost complete skeleton missing most of its skull, most tail vertebra, part of the femur, some spinal and neck vertebra, one claw but it has a well preserved braincase.K
Kagasaurus
"Kagasaurus" is the informal name given to an as yet undescribed genus of dinosaur from the Early Cretaceous. It was a theropod which lived in what is now Japan. The type species was named by Hisa in 1988, but is known from only two teeth. Since "Kagasaurus" has never been formally described, it is considered a nomen nudum. Unlike "Kitadanisaurus" and Katsuyamasaurus, it is unlikely that "Kagasaurus" is synonymous with Fukuiraptor, and may instead be a dromaeosaurid.Katsuyamasaurus
"Katsuyamasaurus" is an informal name for a genus of intermediate theropod known from the Early Cretaceous of the Kitadani Formation, Japan. Known from a single middle caudal vertebra and an ulna, the taxon was informally called "Katsuyama-ryu", until Lambert made it into an invalid genus name, "Katsuyamasaurus". The caudal vertebra was suggested to belong to an ornithopod by Chure, and Olshevsky suggested the material was a synonym of Fukuiraptor. However, the ulna differs from Fukuiraptor, and the large olecranon suggests the taxon falls outside Maniraptoriformes.Kelmayisaurus gigantus
"Kelmayisaurus gigantus" is an informal name for a genus of sauropod known from the Cretaceous. The type species of Kelmayisaurus, K. petrolicus, was first named and described by Chinese paleontologist Dong Zhiming in 1973. A supposed second species, K. "gigantus", was mentioned by Grady in a children book in 1993 as a gigantic vertebral column coming from a 22 m long specimen, but is a nomen nudum and probably does not pertain to Kelmayisaurus. It may be a sauropod instead.Khetranisaurus
"Khetranisaurus" is an informal taxon of titanosaurian sauropod from the Late Cretaceous of Balochistan, western Pakistan. The proposed species is "K. barkhani", described by M. Sadiq Malkani in 2006, and it is based on a tail vertebra, found in the Maastrichtian-age Vitakri Member of the Pab Formation. It was assigned to "Pakisauridae", along with "Pakisaurus" and "Sulaimanisaurus".Koreanosaurus
"Koreanosaurus" is the informal name given to an as-yet undescribed genus of dinosaur from the Early Cretaceous. It was a possible dromaeosaur which lived in what is now Korea, although at times it has been referred to the Tyrannosauridae and Hypsilophodontidae. Based solely on a femur, the name was coined by Kim in 1979, but by 1993 Kim decided that it was a species of Deinonychus, and created the informal name "D." "koreanensis".Kunmingosaurus
"Kunmingosaurus" is an informally named primitive sauropod which lived during the Early Jurassic. Its fossils were found in Yunnan Province, China in 1954. The type and only species is "Kunmingosaurus wudingensis", invalidly coined by Zhao in 1985. It is known from fossils found in the Fengjiahe Formation, including pelvic, hind limb, and vertebral material.L
Lancanjiangosaurus
"Lancanjiangosaurus" is the informal name given to an as yet undescribed genus of sauropod dinosaur from the Middle Jurassic. The "type species", "L. cachuensis", was coined by Zhou in 1985, but remains a nomen nudum. It is known from the Dapuka Group of Tibet.Likhoelesaurus
"Likhoelesaurus" is the name given to an as yet undescribed genus of archosauriform, either a dinosaur or rauisuchian, from the Late Triassic of what is now South Africa. The name was coined by Ellenberger in 1970, and the "type species" is "Likhoelesaurus ingens". It is named after the town in Lesotho where the fossils were found. The only fossils recovered have been teeth, from the late Carnian–early Norian-age Lower Elliot Formation. Ellenberger regarded the genus as a giant carnosaur, and Kitching and Raath treated it as possibly referable to Basutodon. Knoll listed "Likhoelesaurus" as a rauisuchian, also he noted that could also be a rauisuchian.M
Magulodon
"Magulodon" is the name given to an as yet undescribed genus of dinosaur from the Early Cretaceous. It was a possible ornithischian, either an ornithopod or basal ceratopsian, which lived in what is now Maryland, in the United States. The type species, "Magulodon muirkirkensis", was coined by Kranz in 1996. It is a tooth taxon, based solely on a single tooth. Since it has not been formally described, it is also a nomen nudum. It was considered to be an indeterminate specimen in a paper which cited the intended type specimen but avoided using the name to prevent taxonomic clutter.Marisaurus
"Marisaurus" is an informal taxon of titanosaurian sauropod from the Late Cretaceous of Balochistan, western Pakistan. The type species is "M. jeffi", described by M. Sadiq Malkani in 2006, and it is based on tail vertebrae, found in the Maastrichtian-age Vitakri Member of the Pab Formation. Much additional material, including a partial skull, many vertebrae, and a few hindlimb bones, was referred to this genus. "Marisaurus" was assigned to "Balochisauridae" with "Sulaimanisaurus", although the family was used as a synonym of Saltasauridae.Megacervixosaurus
"Megacervixosaurus" is the informal name given to an as yet undescribed genus of herbivorous dinosaur from the Late Cretaceous. It was a titanosaur sauropod which lived in what is now China. The type species, "Megacervixosaurus tibetensis", was coined by Chinese paleontologist Zhao Xijin in 1985. "Megacervixosaurus" has never been formally described, and remains a nomen nudum.Merosaurus
"Merosaurus" is the informal name given to an indeterminate genus of dinosaur from the Early Jurassic of Charmouth, Dorset It originates either from the Blue Lias Formation or the Charmouth Mudstone Formation. It was theropod, possibly a tetanuran which lived in what is now England. The type species, "Merosaurus newmani", was coined by paleontologists Samuel Welles, H.P. Powell, and A. Pickering in 1995, and is based solely on some leg bones once thought to belong to Scelidosaurus.Microcephale
"Microcephale" is the informal name of a genus of very small pachycephalosaurid dinosaur, otherwise known as the "North American dwarf species", which lived during the Late Cretaceous. Its fossils were found in the late Campanian-age Dinosaur Park Formation, in Alberta, Canada. Not much is known about this dinosaur, as it has not yet been fully described; it is therefore a nomen nudum. The fossils of "Microcephale", including tiny skull caps, were first mentioned by paleontologist Paul Sereno in 1997, in a list of pachycephalosaurids. These skull caps measure less than 5 cm each. No potential species name was given.Microdontosaurus
"Microdontosaurus" is the name given to an as yet undescribed genus of sauropod dinosaur from China. It was named from fossils from the Middle Jurassic-age Dapuka Group of Xinjiang. The intended type species is "M. dayensis." As with other informal names created by Zhao in 1985 or 1983, it has not been used since then, and may have been redescribed under another name.Mifunesaurus
"Mifunesaurus" is a nomen nudum given to an extinct non-avian theropod dinosaur from Cenomanian rocks of Japan. "Mifunesaurus" is only known from a few bones, among which are a tibia, a phalanx, a metatarsus and a single tooth. The genus was informally coined by Hisa in 1985.Moshisaurus
Hisa used "Moshisaurus" for sauropod remains from the Early Cretaceous Miyako Group of Japan. Dong et al. and Hasegawa et al. referred them to Mamenchisaurus, but Azuma & Tomida and Barrett et al. assigned them to Sauropoda indet.N
Newtonsaurus
"Newtonsaurus" is an informally named genus erected for the theropod dinosaur species Zanclodon cambrensis, which was discovered in the Lilstock Formation in 1898. It was probably a ceratosaur, which lived in what is now the United Kingdom. The taxon was reassigned to Megalosaurus due to the taxonomic difficulties associated with Zanclodon. It is based on a mold of a dentary from Rhaetian-age beds in Wales, and is one of the relatively few dinosaurs known from the time near the Triassic–Jurassic boundary.Paleontologists have avoided using the name "Newtonsaurus" since its appearance in 1999 in private publications, although "Zanclodon" cambrensis or Megalosaurus cambrensis have both been used for this taxon.
Ngexisaurus
"Ngexisaurus" is the informal name given to an as yet undescribed genus of theropod dinosaur from the Middle Jurassic Dapuka Group of Tibet, China. The type species, "Ngexisaurus dapukaensis", was coined by Zhao in 1983.Nicksaurus
"Nicksaurus" is an informally named Titanosaurian sauropod dinosaur from the Late Cretaceous red muds of the Vitakri Formation of Sulaiman Basin, Pakistan. The dinosaur shared a habitat with other sauropod dinosaurs including Khetranisaurus, Sulaimanisaurus, Pakisaurus, Gspsaurus, Saraikimasoom, and Maojandino.Nurosaurus
"Nurosaurus" is the informal name for a genus of sauropod dinosaur. It is known from a partial, large skeleton, that was presented as soon-to-be-described by Zhiming Dong in 1992, where he gave the proposed binomial "Nurosaurus qaganensis". It was discovered in the Qagannur Formation of Inner Mongolia, southeast of Erenhot. The deposit is younger than the Psittacosaurus-bearing Guyang Group, but is still Early Cretaceous. It was found alongside the plates and scapula of a stegosaur.The foot of "Nurosaurus" is notable for a stress fracture present on the first of the fourth digit of the left foot, which was the first identified fracture of its kind, and have since been identified on the phalanges and metatarsals of Apatosaurus, Barosaurus, Brachiosaurus, Camarasaurus, and Diplodocus.
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Orcomimus
"Orcomimus" is the name given to an as yet undescribed genus of dinosaur from the Late Cretaceous period 66 million years ago. The dinosaur was an ornithomimid which lived in what is now South Dakota, in the United States. The type was coined by Michael Triebold in 1997, but has never been formally described and is currently a nomen nudum. "Orcomimus" was a bipedal theropod, but the dinosaur is known from only a pelvis and a hindlimb. "Orcomimus" is thought to be relatively advanced for other ornithomimids at the time, although this is hard to tell from the limited amount of specimens found of the dinosaur. It may be referable to one of the ornithomimosaur species currently known from the Hell Creek Formation.Oshanosaurus
"Oshanosaurus" is the informal name given to an as yet undescribed genus of sauropod dinosaur from the Early Jurassic period of Yunnan, China. Its fossils were found in the Lower Lufeng Series. The intended "type species", "Oshanosaurus youngi", was coined by Zhao in 1985. It has sometimes been associated with heterodontosaurids, which appears to be due to the juxtaposition of a species of Dianchungosaurus in the text of Zhao.P
Pakisaurus
"Pakisaurus" is an informal taxon of titanosaurian sauropod from the Late Cretaceous of Balochistan, western Pakistan. The proposed species is "P. balochistani", and it was validly named by M. Sadiq Malkani in 2006, based on four tail vertebrae, found in the Maastrichtian-age Vitakri Member of the Pab Formation. Three additional tail vertebrae have been assigned to it. The author erected the family "Pakisauridae", using it synonymously with older Titanosauridae. "Pakisaurus" was decided to be closely related to "Sulaimanisaurus" and "Khetranisaurus", both from Pakistan as well.Podischion
"Podischion" is an informal genus of hadrosaurid dinosaur known from a skeleton discovered in 1911 on the Red Deer River in Alberta by a crew led by Barnum Brown. Skeleton was tentatively named "Podischion", which was not mentioned in published literature until Dingus & Norell. It is possible that the skeleton represents an individual of Hypacrosaurus.R
Ronaldoraptor
"Ronaldoraptor", also known as the “Mitrata” Oviraptorid, is an undescribed oviraptorid from Mongolia and has been listed as "Oviraptor sp." The name was first used by Luis Rey in 2003, in his book A Field Guide to Dinosaurs: The Essential Handbook for Travelers in the Mesozoic, where he drew an illustration, captioning it "Ronaldoraptor". "Ronaldoraptor" may have been closely related to Citipati osmolskae.Rutellum
"Rutellum" is the pre-Linnaean name given to a dinosaur specimen from the Middle Jurassic. It was a sauropod, possibly a cetiosaurid, which lived in what is now England. The specimen, called "Rutellum impicatum", was described in 1699 by Edward Lhuyd, and is notable as the earliest named entity that is recognizable as a dinosaur. It was based on a tooth collected from Caswell, near Witney, Oxfordshire.Because "Rutellum impicatum" was named before 1758, it is not considered a part of modern biological nomenclature.
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Sabinosaurus
"Sabinosaurus" or "Sabinosaurio" is a name used for a partial skeleton from the Sabinas Basin in Mexico. It was initially described as Kritosaurus sp. by Jim Kirkland and colleagues, but considered an indeterminate saurolophine by Prieto-Márquez. This skeleton is about 20% larger than other known specimens, around 11 meters long, and with a distinctively curved ischium, and represents the largest known well-documented North American saurolophine. Unfortunately, the nasal bones are also incomplete in the skull remains from this material.Saldamosaurus
"Saldamosaurus" is an informal genus of stegosaurid dinosaur known from a complete braincase discovered in the Early Cretaceous Saldam Formation of Siberia, Russia. The type species, "Saldamosaurus tuvensis", was named in 2014 but according to Galton and Carpenter it did not meet the requirements of the International Code of Zoological Nomenclature and is hence a nomen nudum,.Saltillomimus
"Saltillomimus" is an informal name for an ornithomimid theropod from the Late Cretaceous of the Cerro del Pueblo Formation in Mexico. It is known from a partial tail, most of a hindlimb, and forelimb bones that was given the name "Saltillomimus rapidus" by Martinez in 2010. Named in his thesis, the taxon name is an invalid nomen ex dissertatione.Sanchusaurus
"Sanchusaurus" is an informal name for an ornithomimosaur dinosaur from the Early Cretaceous period of Asia. It is only known by a partial tail vertebra, found in Nakasato, Japan. Dong considered it synonymous with Gallimimus but the large discrepancy in both age and location between the two species renders this opinion untenable. The genus has not been formally described and is considered a nomen nudum. It was first mentioned by Hisa in 1985.Saraikimasoom
"Saraikimasoom" is an invalid species of titanosaur dinosaur from the Vitakri Formation in Pakistan. The type species, Saraikimasoom vitakri, was described by Sadiq Malkhani in 2015, in a paper describing multiple Pakistani dinosaurs, such as Gspsaurus, "Nicksaurus" and "Maojandino". Saraikimasoom is currently recognised as a nomen manuscriptum.Shake-N-Bake theropod
The "Shake-N-Bake theropod" is an undescribed species of coelophysoid from the Kayenta Formation.Siamodracon
"Siamodracon" is an extinct genus of invalid stegosaurid dinosaur known from a single dorsal vertebra found in Thailand's Phu Kradung Formation. According to Galton and Carpenter it did not meet the requirements of the International Code of Zoological Nomenclature. "Siamodracon" was the first thyreophoran dinosaur discovered in South East Asia.Sidormimus
"Sidormimus" is an informal genus of noasaurid discovered in the Elrhaz Formation in Niger. It was discovered in 2000 by Chris Sidor and it was immediately described by Lyon on the Project Exploration website, with a photograph of the holotype. During the same year, on the National Geographic website, the same photograph of the holotype was labelled "Dongosaurus". In 2005, Sidor himself confirmed that "Sidormimus" was the Elrhaz noasaurid. "Sidormimus" has been mentioned by Paul Sereno three times. "Sidormimus" is known from a partial post cranial skeleton. Its neck and ribs were exposed when the holotype was discovered.Sinopeltosaurus
"Sinopeltosaurus" is a dubious genus of extinct scelidosaurid ornithischian dinosaur described by Roman Ulansky. The type and only species is "S. minimus" of the lower Jurassic Lufeng Formation of Yunnan China, based on an articulated set of ankle bones. In 2016, Peter Malcolm Galton and Kenneth Carpenter identified it as a nomen dubium, and listed it as Ornithischia indet., possible Thyreophora indet. Ulansky variously referred to it as "Sinopeltosaurus minimus" or "Sinopelta minima"; Galton and Carpenter, as the first revisers under ICZN, made the former official.Suciasaurus
A fossil theropod nicknamed "Suciasaurus rex" was discovered in 2012 at Sucia Island State Park in San Juan County of the U.S. State of Washington. It was the first dinosaur discovered in Washington state. The finding was announced when Burke Museum paleontologists published a discovery paper in PLoS ONE. Prompted by a petition from students at an elementary school at Parkland, near Tacoma, the Washington State Legislature introduced a bill in 2019 to make it the official state dinosaur.Sugiyamasaurus
"Sugiyamasaurus" is the informal name given to a few spatulate teeth belonging to a titanosauriform, possibly Fukuititan, which lived in Japan during the Early Cretaceous. The name was first printed by David Lambert in 1990 in the Dinosaur Data Book, and also appears in Lambert's Ultimate Dinosaur Book and in many on-line lists of dinosaurs. Since it has not been formally described, "Sugiyamasaurus" is a nomen nudum. Remains were found near Katsuyama City and were initially referred to Camarasauridae, but might belong to Fukutitan because they were unearthed in the same quarry as the Fukuititan material.Sulaimanisaurus
"Sulaimanisaurus" is an informal taxon of titanosaurian sauropod from the Late Cretaceous of Balochistan, western Pakistan. The proposed species is "S. gingerichi", described by M. Sadiq Malkani in 2006, and it is based on seven tail vertebra, found in the Maastrichtian-age Vitakri Member of the Pab Formation. Four additional tail vertebrae have been assigned to it. It was considered to be related to "Pakisaurus" and "Khetranisaurus" in the family "Pakisauridae".T
Teihivenator
"Teihivenator" is an improperly named taxon of tyrannosauroid coelurosaur from the Navesink Formation of New Jersey. It was suggested to contain the species, "T." macropus, originally classified as a species of Dryptosaurus. It was suggested as a separate genus in 2017 by Chan-gyu Yun. The name "Teihivenator" is invalid because the publication naming it is online-only, which means that a registration with ZooBank is required to be present in the article when published. However, the ZooBank registry was only added in after initial publication, meaning that it fails the requirement to be a validly published taxon.In 2017, a preprint paper by Chase Brownstein concluded that the remains of L. macropus are a mixture of tyrannosauroid and ornithomimid elements with no distinguishing characteristics, rendering the species a chimera and a nomen dubium. In 2018, Brownstein stated that a tibia of L. macropus catalogued as specimen AMNH FARB 2550 represents a tyrannosauroid that probably was distinct from Dryptosaurus, but not sufficiently to base a taxon on.