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Eoraptor Temporal range: Late Triassic (Carnian), 231–228 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Reconstructed skeleton, Royal Ontario Museum
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	†Sauropodomorpha
Genus:	†Eoraptor Sereno et al. 1993
Species:	†E. lunensis
Binomial name
†Eoraptor lunensis Sereno et al. 1993

Eoraptor (/ˈiːoʊˌræptər/) is a genus of small, lightly built, basal sauropodomorph dinosaur. One of the earliest-known dinosaurs and one of the earliest sauropodomorphs, it lived approximately 231 to 228 million years ago, during the Late Triassic in Western Gondwana, in the region that is now northwestern Argentina. The type and only species, Eoraptor lunensis, was first described in 1993, and is known from an almost complete and well-preserved skeleton and several fragmentary ones. Eoraptor had multiple tooth shapes, which suggests that it was omnivorous.

History of discovery

The bones of this primitive dinosaur were first discovered in 1991, by University of San Juan paleontologist Ricardo Martínez, during field work conducted by the University of Chicago and the University of San Juan. The holotype specimen PVSJ 512 was discovered in muddy siltstone belonging to the Cancha de Bochas Member of the Ischigualasto Formation in Argentina. The fossils in this formation were deposited in the Carnian stage of the Triassic period, approximately 235 to 228 million years ago. It took almost 12 months to collect the holotype, which was then shipped to the Field Museum of Natural History in Chicago for preparation by William F. Simpson and Bob Masek. The fossil was first put on display in Chicago and was then returned to San Juan, Argentina, where it went on display at the Museum of Natural Sciences.

The genus Eoraptor was described and named by Paul Sereno, Catherine Forster, Raymond R. Rogers, and Alfredo M. Monetta in 1993. The name is derived from the Greek word eós (ἠώς) meaning 'dawn', a reference to its primitive nature, and the Latin word raptor meaning 'plunderer', a reference to its presumed carnivorous nature and its grasping hand. The specific name lunensis is derived from the Latin words luna ('moon') and the suffix -ensis ('inhabitant'), a reference to its place of discovery: the Valle de la Luna ('Valley of the Moon'), so named for its arid, otherworldly appearance evocative of a lunar landscape. The type species Eoraptor lunensis means 'dawn plunderer from the Valley of the Moon'.

Description

Eoraptor was a small dinosaur, with the known specimens measuring 1.2–1.3 m (3.9–4.3 ft) in length, and weighing around or less than 10 kg (22 lb). It had a lightly built skull with a slightly enlarged external naris. As in early sauropodomorphs such as Buriolestes and Pampadromaeus and coelophysoids (which would appear millions of years later), Eoraptor had a kink in its upper jaws, between the maxilla and the premaxilla. Paul Sereno et al. (2013) observed that the lower jaw had a mid-mandibular joint. It ran digitigrade, and upright on its hind legs. The femur of the holotype specimen PVSJ 512 is 152 millimetres (6.0 in), and the tibia is 157 millimetres (6.2 in), suggesting that it was a fast runner. Its forelimbs are only half the length of its hindlimbs, suggesting that it was bipedal. All of its long bones have hollow shafts. Eoraptor had five digits on each 'hand', the three longest of which ended in large claws and were presumably used to handle prey. Scientists have surmised that the fourth and fifth digits were too tiny to be of any use in hunting. The ilium is supported by three sacral vertebrae (atypical of the plesiomorphic two sacrals of basal sauropodomorphs), unlike that of the coeval Herrerasaurus which is supported by only two sacrals, a basal trait. Eoraptor had vertebral centra that are hollow, a feature present in some of its ancestors.

The original describers, Paul Sereno et al. (1993), supported the notion that Eoraptor was an adult specimen based on the closure of sutures in the vertebral column, and the partial fusion of the scapulocoracoid. Bonaparte (1996) interpreted the relatively large orbital opening in the skull as a juvenile trait. Ronald Tykoski agreed (2005) and suggested that certain skull features of the type specimen suggested that it was young, specifically, the skull bones are not completely fused, relatively large orbits, and a short snout. Later Sereno et al. (2013) considered the type specimen as a young adult approaching skeletal maturity, considering that it contained traits of both maturity and immaturity.

According to Sereno et al. (1993), Eoraptor can be distinguished based on the fact that its premaxillary and anterior maxillary teeth are leaf-shaped, the external nares are slightly enlarged, and the premaxilla is observed to have a slender posterolateral process. Max Langer and Michael Benton (2006) noted that Eoraptor can be distinguished based on the fact that the proximal part of its fibula is extremely transversely compressed.

Classification

In 1993 Paul Sereno and his colleagues described and named Eoraptor, and determined it to be one of the earliest dinosaurs. Its age was determined by several factors, not least because it lacked the specialized features of any of the major groups of later dinosaurs, including its lack of specialized predatory features. In 1995, Sereno posited that Eoraptor is the earliest-recorded theropod, and is closest to "the hypothetical dinosaurian condition than any other dinosaurian subgroup." The precise placement of Eoraptor within Dinosauria has been unstable, with opinion often varying between a basal saurischian and a basal theropod. When it was first described by Sereno and Forster in 1993, it was regarded as a theropod, based on its "functionally tridactyl hand" and other anatomical features. In 2011, a study conducted by Hans-Dieter Sues, Sterling J. Nesbitt, David S. Berman and Amy C. Henrici featuring a description of Daemonosaurus, also concluded that there is now enough fossil evidence to confidently classify Eoraptor as a theropod. The study noted that the "transitional suite of character states" of the recently discovered dinosaurs, Daemonosaurus and Tawa further support that Eoraptor is a basal theropod, and not a basal saurischian or a basal sauropodomorph. On the other hand, several studies from 2012 onward have recovered Eoraptor as an early sauropodomorph, rather than a theropod. The following phylogenetic tree illustrates the relationships of Eoraptor among the major theropod groups based on various studies conducted in the 2010s.

Philip Currie (1997) found Eoraptor anatomically closer to what would be considered the ancestral morphotype of both saurischian and ornithischian dinosaurs. In 2011, Martinez et al. (the team that described Eodromaeus) found Eoraptor to be a basal sauropodomorph, with characteristic features from the group. Michael Benton expressed his hesitation to this, and claimed that it is "quite a shift" to remove Eoraptor from Theropoda and then place it in Sauropodomorpha. A subsequent study by Apaldetti, Martinez, Alcober, and Pol published in 2011 found Eoraptor to be a saurischian close to sauropodomorphs and theropods, though was unable to resolve which of the two branches, if either, it fell within. Sereno et al. (2013) redescribed the holotype skeleton and concluded that Eoraptor was not a theropod but a basal sauropodomorph, consistent with the earlier observation made by Martinez et al. (2011).

A large phylogenetic analysis of early dinosaurs by Matthew Baron, David Norman and Paul Barrett (2017) found Eoraptor to be the earliest diverging member of Theropoda, within the larger clade Ornithoscelida. A phylogenetic analysis published with the description of new Buriolestes remains in 2018, based on Langer et al. (2017) placed Eoraptor in a clade of early sauropodomorphs, alongside Buriolestes, Panphagia, Pampadromaeus, and Saturnalia.

Paleobiology

Eoraptor is thought to have been an omnivore, although its dentition is quite similar to that of Buriolestes, which is considered carnivorous. It was a swift sprinter and, upon catching its prey, it would use claws and teeth to tear the prey apart. Unlike later, carnivorous dinosaurs, it lacked a sliding joint at the articulation of the lower jaw, with which to hold large prey. Furthermore, only some of its teeth were curved and saw-edged, unlike those in the mouths of later theropods. The heterodont dentition of Eoraptor consists of both serrated, recurved teeth in the upper jaw, like the teeth of theropods, and leaf-shaped teeth in the lower jaw, like the teeth of basal sauropodomorphs. Eoraptor had 4 teeth in the premaxilla and 18 teeth in the maxilla, a dental formula not dissimilar to that of Herrerasaurus.

Paleoecology

During the Late Triassic period, the Ischigualasto Formation was a volcanically active floodplain covered by forests, with a warm and humid climate, but subject to seasonal variations including strong rainfall. Vegetation consisted of ferns, horsetails, and giant conifers, which formed highland forests along the banks of rivers. Herrerasaurus remains appear to have been the most common among the carnivores of the Ischigualasto Formation. Sereno (1993) noted that Eoraptor was found in "close association" with therapsids, rauisuchians, archosaurs, Saurosuchus and the dinosaurs Herrerasaurus and Pisanosaurus, all of whom lived in its paleoenvironment. Herbivores were represented by rhynchosaurs such as Hyperodapedon; aetosaurs; cynodonts like Chiniquodon, kannemeyeriid dicynodonts such as Ischigualastia; and traversodontids such as Exaeretodon. These non-dinosaurian herbivores were much more abundant than early dinosaurs. Dinosaur fossils, including those of Eoraptor only represent approximately 6% of the total sample that has been recovered from the Ischigualasto Formation (Rogers et al., 1993), which suggests that dinosaurs were less numerous than other tetrapods.

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External links

• Media related to Eoraptor at Wikimedia Commons
• Data related to Eoraptor at Wikispecies
• Paul Sereno's paleontology website
• Paleobiology Database entry
• Eoraptor lunensis at DigiMorph

v t e Theropoda
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Clade: Avemetatarsalia Clade: Dinosauria Avemetatarsalia see Avemetatarsalia Theropoda see below↓
Theropoda Theropoda Chindesaurus? Daemonosaurus? Eodromaeus? Erythrovenator Guaibasaurus? Nhandumirim? Tawa? Herrerasauria? Neotheropoda Dilophosaurus Dolichosuchus? Dracovenator Gojirasaurus Lepidus Liliensternus Lophostropheus Notatesseraeraptor Sarcosaurus Shuangbaisaurus Sinosaurus Tachiraptor Velocipes? Zupaysaurus Coelophysoidea Dracoraptor? Panguraptor Pendraig Podokesaurus Powellvenator Coelophysidae Camposaurus Coelophysis Lucianovenator Megapnosaurus? Panguraptor? Procompsognathus Pterospondylus? Segisaurus Averostra see below↓ Dubious neotheropods Teinurosaurus Halticosaurus
Averostra Averostra Dornraptor Lophostropheus? Ceratosauria Berberosaurus Fosterovenator? Jubbulpuria Lukousaurus? Saltriovenator Ceratosauridae Ceratosaurus Genyodectes Abelisauroidea Betasuchus? Lametasaurus? Ornithomimoides? Ozraptor? Noasauridae Afromimus? Austrocheirus? Berthasaura Compsosuchus? Dahalokely? Deltadromeus? Genusaurus? Kiyacursor Ligabueino Spinostropheus Elaphrosaurinae Elaphrosaurus Huinculsaurus Limusaurus Noasaurinae Laevisuchus Masiakasaurus Noasaurus Velocisaurus Vespersaurus Abelisauridae Chenanisaurus Dryptosauroides? Eoabelisaurus Indosuchus Kryptops Kurupi Rugops Spectrovenator Tarascosaurus Tralkasaurus Xenotarsosaurus Majungasaurinae Arcovenator Dahalokely? Genusaurus Indosaurus Majungasaurus Rahiolisaurus? Rajasaurus Carnotaurinae Majungasaurinae? Brachyrostra Dahalokely? Ekrixinatosaurus Elemgasem Guemesia Ilokelesia Llukalkan Niebla Rahiolisaurus? Skorpiovenator Thanos Furileusauria Abelisaurus Aucasaurus Caletodraco Carnotaurus Elemgasem? Koleken Pycnonemosaurus Quilmesaurus Viavenator Tetanurae see below↓
Tetanurae Tetanurae Calamospondylus? Chienkosaurus? Chilesaurus? Chuandongocoelurus Cruxicheiros? Cryolophosaurus Kaijiangosaurus Kayentavenator Monolophosaurus Pandoravenator Sinosaurus? Szechuanosaurus Vectaerovenator Orionides Megalosauroidea Yunyangosaurus Piatnitzkysauridae Condorraptor Marshosaurus Piatnitzkysaurus Xuanhanosaurus? Megalosauria Streptospondylus? Megalosauridae Eustreptospondylus Megalosaurinae Duriavenator Megalosaurus Torvosaurus Wiehenvenator Afrovenatorinae Afrovenator Dubreuillosaurus Leshansaurus Magnosaurus Piveteausaurus Poekilopleuron? Spinosauridae Camarillasaurus? Cristatusaurus Iberospinus Ostafrikasaurus? Baryonychinae Baryonyx Protathlitis Riojavenatrix Suchosaurus? Vallibonavenatrix? Ceratosuchopsini Ceratosuchops Riparovenator Suchomimus Spinosaurinae Camarillasaurus? Ichthyovenator Irritator Oxalaia Siamosaurus Spinosaurini Sigilmassasaurus Spinosaurus Avetheropoda see below↓
Avetheropoda Avetheropoda Gasosaurus? Lourinhanosaurus? Carnosauria Altispinax Monolophosaurus? Megalosauridae? Spinosauridae? Allosauroidea Asfaltovenator Erectopus Xuanhanosaurus? Piatnitzkysauridae? Metriacanthosauridae Xuanhanosaurus? Yangchuanosaurus Metriacanthosaurinae Alpkarakush Metriacanthosaurus Shidaisaurus Siamotyrannus Sinraptor Allosauria Allosauridae Allosaurus Antrodemus? Epanterias? Saurophaganax? Carcharodontosauria Datanglong Lusovenator Siamraptor Siats? Ulughbegsaurus? Veterupristisaurus Neovenatoridae Chilantaisaurus? Gualicho? Neovenator Siats? Megaraptora? Carcharodontosauridae Acrocanthosaurus Altispinax? Concavenator Eocarcharia Kelmayisaurus Lajasvenator Sauroniops Shaochilong Ulughbegsaurus? Veterupristisaurus Carcharodontosaurinae Carcharodontosaurus Giganotosaurini Giganotosaurus Mapusaurus Meraxes Taurovenator Tyrannotitan Megaraptora? Aoniraptor Bahariasaurus? Deltadromeus? Fukuiraptor Phuwiangvenator Rapator Siats? Chilantaisaurus? Megaraptoridae Aerosteon Australovenator Maip Megaraptor Murusraptor Orkoraptor Tratayenia Coelurosauria see below↓
Coelurosauria Coelurosauria Aratasaurus Asiamericana Bahariasaurus? Bicentenaria Chilantaisaurus? Gualicho? Richardoestesia Sciurumimus? Vayuraptor Xinjiangovenator Zuolong Tyrannoraptora Tyrannosauroidea Chingkankousaurus Labocania? Coeluridae? Coelurus Tanycolagreus? Proceratosauridae Guanlong Kileskus Proceratosaurus Sinotyrannus Yutyrannus Pantyrannosauria Alectrosaurus Aviatyrannis Bagaraatan? Dilong Eotyrannus Jinbeisaurus Juratyrant Moros Santanaraptor Stokesosaurus Suskityrannus Timimus? Timurlengia Xiongguanlong Megaraptora? Eutyrannosauria Appalachiosaurus Bistahieversor? Dryptosaurus Tyrannosauridae Albertosaurinae Albertosaurus Gorgosaurus Tyrannosaurinae Asiatyrannus Nanuqsaurus Alioramini Alioramus Qianzhousaurus Daspletosaurini Daspletosaurus Thanatotheristes Teratophoneini Bistahieversor? Dynamoterror Labocania? Lythronax Teratophoneus Tyrannosaurini Tarbosaurus Tyrannosaurus Zhuchengtyrannus Maniraptoromorpha see below↓ Dubious coelurosaurs Iliosuchus Kakuru Phaedrolosaurus Shanyangosaurus
Maniraptoromorpha Maniraptoromorpha Coelurus? Juravenator Ornitholestes Neocoelurosauria Aniksosaurus Compsognathidae Aniksosaurus? Aristosuchus Beipiaognathus? Compsognathus Huaxiagnathus Mirischia Scipionyx? Sinocalliopteryx Sinosauropteryx Xunmenglong Maniraptoriformes Compsognathidae? Ornithomimosauria Arkansaurus Aviatyrannis? Calamosaurus? Hexing Kinnareemimus Nedcolbertia Nqwebasaurus Thecocoelurus? Valdoraptor Macrocheiriformes Harpymimus Pelecanimimus Shenzhousaurus Deinocheiridae Beishanlong Deinocheirus Garudimimus Harpymimus? Paraxenisaurus? Tyrannomimus Ornithomimidae Aepyornithomimus Anserimimus Archaeornithomimus "Coelosaurus" Dromiceiomimus Gallimimus Ornithomimus Qiupalong Rativates Sinornithomimus Struthiomimus Tototlmimus Maniraptora see Maniraptora includes birds

v t e Sauropodomorpha
Kingdom: Animalia Phylum: Chordata Class: Sauropsida Clade: Avemetatarsalia Clade: Dinosauria Avemetatarsalia see Avemetatarsalia Sauropodomorpha see below↓
Sauropodomorpha Sauropodomorpha Buriolestes Eoraptor Gigantoscelus Guaibasaurus Mbiresaurus Pampadromaeus Panphagia Saturnaliidae Buriolestes? Eoraptor? Chromogisaurus Nhandumirim Pampadromaeus? Panphagia? Saturnalia Bagualosauria Arcusaurus Asylosaurus Bagualosaurus Efraasia Nambalia Pantydraco Thecodontosaurus Unaysauridae Jaklapallisaurus Macrocollum Unaysaurus Plateosauria Plateosauravus Ruehleia Xixiposaurus Plateosauridae Euskelosaurus Gresslyosaurus Issi Pachysauriscus Plateosaurus Yimenosaurus Massopoda Gryponyx Gyposaurus Ignavusaurus Kholumolumo Musankwa Sarahsaurus Tuebingosaurus Riojasauridae Eucnemesaurus Riojasaurus Massospondylidae Adeopapposaurus Coloradisaurus Glacialisaurus Ignavusaurus? Leyesaurus Lufengosaurus Massospondylus Ngwevu Pradhania Sarahsaurus Xingxiulong? Sauropodiformes Chuxiongosaurus? Jingshanosaurus Lishulong Qianlong Seitaad Xingxiulong? Yizhousaurus Yunnanosaurus Anchisauria Aardonyx Anchisaurus Camelotia Irisosaurus Lamplughsaura Leonerasaurus Melanorosaurus Meroktenos Mussaurus Pulanesaura Sefapanosaurus Sauropoda see below↓
Sauropoda Sauropoda Amygdalodon Blikanasaurus Chinshakiangosaurus Gongxianosaurus Isanosaurus Leonerasaurus? Pulanesaura? Protognathosaurus Schleitheimia Tuebingosaurus? Lessemsauridae Antetonitrus Ingentia Ledumahadi Lessemsaurus Gravisauria Archaeodontosaurus? Kotasaurus Ohmdenosaurus Rhoetosaurus Sanpasaurus? Zizhongosaurus? Vulcanodontidae Tazoudasaurus Vulcanodon Eusauropoda Algoasaurus Asiatosaurus Bagualia Barapasaurus Bellusaurus Cetiosauriscus Dashanpusaurus Dystrophaeus Janenschia Jobaria Nebulasaurus Perijasaurus Shunosaurus Spinophorosaurus Tehuelchesaurus Volkheimeria Cetiosauridae Cetiosaurus Chebsaurus Ferganasaurus? Lapparentosaurus? Patagosaurus? Mamenchisauridae Analong Anhuilong Cetiosauriscus? Chuanjiesaurus Datousaurus? Eomamenchisaurus Huangshanlong Hudiesaurus Jingiella Klamelisaurus? Mamenchisaurus Omeisaurus Qijianglong Rhomaleopakhus Tienshanosaurus Tonganosaurus Wamweracaudia Xinjiangtitan Yuanmousaurus Zigongosaurus Turiasauria Amanzia Bellusaurus? Haestasaurus? Janenschia? Losillasaurus Mierasaurus Moabosaurus Narindasaurus Oplosaurus? Tehuelchesaurus? Tendaguria Turiasaurus Zby Neosauropoda Diplodocoidea (see below ↓ ) Macronaria (see below ↓ ) Dubious sauropods Bothriospondylus Cardiodon Dinodocus Gigantosaurus Neosodon Qinlingosaurus Ultrasaurus
Diplodocoidea Diplodocoidea Haplocanthosaurus Diplodocimorpha Rebbachisauridae Agustinia Amazonsaurus Campananeyen Comahuesaurus Dzharatitanis? Histriasaurus Lavocatisaurus Maraapunisaurus? Nopcsaspondylus Sidersaura Xenoposeidon Zapalasaurus Khebbashia Limaysaurinae Cathartesaura Limaysaurus Rayososaurus? Rebbachisaurinae Demandasaurus Itapeuasaurus Katepensaurus Nigersaurus Rebbachisaurus Tataouinea Flagellicaudata Dicraeosauridae Amargasaurus Amargatitanis Bajadasaurus Brachytrachelopan Dicraeosaurus Dyslocosaurus? Kaatedocus Lingwulong Pilmatueia Smitanosaurus Suuwassea Tharosaurus Diplodocidae Apatosaurinae Amphicoelias? Apatosaurus Atlantosaurus? Brontosaurus Diplodocinae Ardetosaurus Barosaurus Dinheirosaurus Diplodocus Galeamopus Kaatedocus? Leinkupal Supersaurus Tornieria
Macronaria Macronaria Abrosaurus Aragosaurus Bashunosaurus? Daanosaurus Dashanpusaurus? Europasaurus Haestasaurus? Yuzhoulong Camarasauridae Camarasaurus Lourinhasaurus Titanosauriformes Astrodon Duriatitan Eucamerotus Fushanosaurus Fusuisaurus Ornithopsis Pelorosaurus Rugocaudia? Brachiosauridae Abydosaurus Atlasaurus Brachiosaurus Cedarosaurus Galvesaurus? Giraffatitan Lusotitan Sonorasaurus Soriatitan Venenosaurus Vouivria Somphospondyli Angolatitan Arkharavia Astrophocaudia Austrosaurus Brohisaurus Brontomerus Chubutisaurus Dongbeititan Europatitan Fukuititan Garumbatitan Jiangxititan? Jiutaisaurus Liaoningotitan Ligabuesaurus? Liubangosaurus Oceanotitan Padillasaurus Pukyongosaurus Ruixinia Sauroposeidon Sibirotitan Tastavinsaurus Triunfosaurus Euhelopodidae Australodocus? Chiayusaurus? Erketu Euhelopus Gannansaurus Gobititan Huabeisaurus Huanghetitan Jiangshanosaurus? Phuwiangosaurus Qiaowanlong Silutitan Tambatitanis Tangvayosaurus Yongjinglong Yunmenglong Diamantinasauria Australotitan Diamantinasaurus Sarmientosaurus Savannasaurus Wintonotitan? Titanosauria see below↓
Titanosauria Titanosauria Abdarainurus Aegyptosaurus? Andesaurus Angolatitan? Arackar Argyrosaurus Atacamatitan Austroposeidon Baotianmansaurus Barrosasaurus Baurutitan? Bonatitan? Borealosaurus Brasilotitan Choconsaurus Daxiatitan Dongyangosaurus Dreadnoughtus? Elaltitan Epachthosaurus? Gandititan Hamititan Huabeisaurus Jiangshanosaurus? Kaijutitan Karongasaurus Laplatasaurus Ligabuesaurus? Magyarosaurus Malarguesaurus? Malawisaurus Mnyamawamtuka Narambuenatitan Ninjatitan Normanniasaurus Nullotitan Pellegrinisaurus? Petrobrasaurus Pitekunsaurus Rapetosaurus Rukwatitan Ruyangosaurus Tastavinsaurus? Tengrisaurus? Tiamat Traukutitan Trigonosaurus Sonidosaurus Uberabatitan Volgatitan Xianshanosaurus Diamantinasauria? Lirainosaurinae Ampelosaurus Atsinganosaurus Garrigatitan Lirainosaurus Lohuecotitan Mansourasaurus Paludititan Eutitanosauria Inawentu Menucocelsior Colossosauria Antarctosaurus Baalsaurus Bonitasaura Chucarosaurus Epachthosaurus? Jainosaurus Quetecsaurus Tengrisaurus? Vahiny Rinconsauria Adamantisaurus Maxakalisaurus? Muyelensaurus Overosaurus Panamericansaurus Rinconsaurus Aeolosaurini Aeolosaurus Arrudatitan Bravasaurus Caieiria Gondwanatitan Punatitan Shingopana Lognkosauria Argentinosaurus Drusilasaura Dzharatitanis? Futalognkosaurus Jiangxititan? Mendozasaurus Notocolossus Patagotitan Puertasaurus Saltasauroidea Bustingorrytitan Titanomachya Udelartitan Nemegtosauridae Nemegtosaurus Quaesitosaurus? Tapuiasaurus? Saltasauridae Igai Isisaurus? Qingxiusaurus Quaesitosaurus? Opisthocoelicaudiinae Abditosaurus? Alamosaurus Baurutitan? Dreadnoughtus? Opisthocoelicaudia Pellegrinisaurus? Qunkasaura Zhuchengtitan? Saltasaurinae Abditosaurus? Bonatitan? Ibirania Maxakalisaurus? Neuquensaurus Paralititan Rocasaurus Saltasaurus Yamanasaurus Dubious titanosaurs Bruhathkayosaurus? Campylodoniscus Clasmodosaurus Hypselosaurus Iuticosaurus Loricosaurus Macrurosaurus? Microcoelus Mongolosaurus? Titanosaurus
Topics in sauropodomorph research Sauropod neck posture Sauropod hiatus List of sauropod species

• Argentina
• Dinosaurs
• Paleontology

• Sauropodomorphs of South America
• Dinosaur genera
• Carnian genera
• Late Triassic dinosaurs of South America
• Fossils of Argentina
• Ischigualasto Formation
• Fossil taxa described in 1993
• Taxa named by Paul Sereno
• Late Triassic sauropodomorphs
• Monotypic sauropodomorph genera