Editing Allosaurus (section)

==Discovery and history==

===Early discoveries and research===
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| image1            = AMNH Allosaurus.jpg
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| caption1          = Mounted ''A. fragilis'' specimen (AMNH 5753), posed as scavenging an ''[[Apatosaurus]]''
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| caption2          = AMNH 5753 in a [[Charles R. Knight]] life restoration (Outdated)
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The discovery and early study of ''Allosaurus'' is complicated by the multiplicity of names coined during the [[Bone Wars]] of the late 19th century. The first described [[fossil]] in this history was a bone obtained secondhand by [[Ferdinand Vandeveer Hayden]] in [[1869 in paleontology|1869]]. It came from [[Middle Park (Colorado basin)|Middle Park]], near [[Granby, Colorado]], probably from [[Morrison Formation]] rocks. The locals had identified such bones as "petrified horse hoofs". Hayden sent his specimen to [[Joseph Leidy]], who identified it as half of a tail vertebra and tentatively assigned it to the European dinosaur genus ''[[Poekilopleuron]]'' as ''Poicilopleuron''{{sic}} ''valens''.<ref name="JL70">{{cite journal |last=Leidy |first=Joseph |author-link=Joseph Leidy |year=1870 |title=Remarks on ''Poicilopleuron valens'', ''Clidastes intermedius'', ''Leiodon proriger'', ''Baptemys wyomingensis'', and ''Emys stevensonianus'' |journal=Proceedings of the Academy of Natural Sciences of Philadelphia |volume=22 |pages=3–4}}</ref> He later decided it deserved its own genus, ''Antrodemus''.<ref name=JL73>{{cite journal |last=Leidy |first=Joseph |year=1873 |title=Contribution to the extinct vertebrate fauna of the western territories |journal=Report of the U.S. Geological Survey of the Territories I |pages=14–358}}</ref>

''Allosaurus'' itself is [[Holotype|based on]] [[Peabody Museum of Natural History|YPM]] 1930, a small collection of fragmentary bones including parts of three vertebrae, a rib fragment, a tooth, a toe bone, and (most useful for later discussions) the shaft of the right humerus (upper arm). [[Othniel Charles Marsh]] gave these remains the formal name ''Allosaurus fragilis'' in 1877. ''Allosaurus'' comes from the [[Ancient Greek|Greek]] words ''{{lang|grc-Latn|allos}}/{{lang|grc|αλλος}}'', meaning "strange" or "different", and ''{{lang|grc-Latn|sauros}}/{{lang|grc|σαυρος}}'', meaning "lizard" or "reptile".<ref>{{cite book|author=Liddell & Scott|year=1980|title=Greek–English Lexicon, Abridged Edition|publisher=Oxford University Press|location=Oxford|isbn=978-0-19-910207-5|oclc=17396377|url=https://archive.org/details/lexicon00lidd}}</ref> It was named 'different lizard' because its vertebrae were different from those of other dinosaurs known at the time of its discovery.<ref name="OCM77">{{cite journal |last=Marsh |first=Othniel Charles |author-link=Othniel Charles Marsh |year=1877 |title=Notice of new dinosaurian reptiles from the Jurassic formation |url=https://zenodo.org/record/1450040 |journal=American Journal of Science and Arts |volume=14 |issue=84 |pages=514–516 |bibcode=1877AmJS...14..514M |doi=10.2475/ajs.s3-14.84.514 |s2cid=130488291 |archive-date=April 20, 2021 |access-date=August 31, 2020 |archive-url=https://web.archive.org/web/20210420181422/https://zenodo.org/record/1450040 |url-status=live }}</ref><ref name=DMLomnipedia>{{cite web|url=http://www.dinosauria.com/dml/names/dinoa.htm |title=Dinosauria Translation and Pronunciation Guide A |access-date=September 11, 2007 |last=Creisler |first=Ben |date=July 7, 2003 |publisher=Dinosauria On-Line |archive-url=https://web.archive.org/web/20100105101204/http://www.dinosauria.com/dml/names/dinoa.htm |archive-date=January 5, 2010 |url-status=dead}}</ref> The species epithet ''fragilis'' is [[Latin]] for "fragile", referring to lightening features in the vertebrae. The bones were collected from the Morrison Formation of [[Garden Park, Colorado|Garden Park]], north of [[Cañon City, Colorado|Cañon City]].<ref name=OCM77/> O. C. Marsh and [[Edward Drinker Cope]], who were in scientific competition with each other, went on to coin several other genera based on similarly sparse material that would later figure in the taxonomy of ''Allosaurus''. These include Marsh's ''Creosaurus''<ref name=OCM78/> and ''Labrosaurus'',<ref name=OCM79>{{cite journal |last=Marsh |first=Othniel Charles |year=1879 |title=Principal characters of American Jurassic dinosaurs. Part II |journal=American Journal of Science |series=Series 3 |volume=17 |issue=97 |pages=86–92 |doi=10.2475/ajs.s3-17.97.86 |url=https://babel.hathitrust.org/cgi/imgsrv/download/pdf?id=hvd.32044107172876;orient=0;size=100;seq=5;attachment=0 |hdl=2027/hvd.32044107172876 |s2cid=219247096 |hdl-access=free |archive-date=November 9, 2021 |access-date=August 6, 2018 |archive-url=https://web.archive.org/web/20211109005146/https://babel.hathitrust.org/cgi/imgsrv/download/pdf?id=hvd.32044107172876;orient=0;size=100;seq=5;attachment=0 |url-status=live }}</ref> as well as Cope's ''Epanterias''.<ref name=EDC78/>

In their haste, Cope and Marsh did not always follow up on their discoveries (or, more commonly, those made by their subordinates). For example, after the discovery by [[Benjamin Franklin Mudge|Benjamin Mudge]] of the type specimen of ''Allosaurus'' in Colorado, Marsh elected to concentrate work in [[Wyoming]]. When work resumed at Garden Park in [[1883 in paleontology|1883]], M. P. Felch found an almost complete ''Allosaurus'' and several partial skeletons.<ref name=DBN85/> In addition, one of Cope's collectors, H. F. Hubbell, found a specimen in the [[Como Bluff]] area of Wyoming in [[1879 in paleontology|1879]], but apparently did not mention its completeness and Cope never unpacked it. Upon unpacking it in [[1903 in paleontology|1903]] (several years after Cope had died), it was found to be one of the most complete theropod specimens then known and the skeleton, now cataloged as AMNH 5753, was put on public view in [[1908 in paleontology|1908]].<ref name=NGD95>{{cite book |last1=Norell |first1=Mark A. |last2=Gaffney, Eric S. |last3=Dingus, Lowell |title=Discovering Dinosaurs in the American Museum of Natural History |publisher=Knopf |location=New York |year=1995 |pages=[https://archive.org/details/discoveringdinos00nore_0/page/112 112–113] |isbn=978-0-679-43386-6 |url=https://archive.org/details/discoveringdinos00nore_0/page/112 }}</ref> This is the well-known mount poised over a partial ''[[Apatosaurus]]'' skeleton as if [[Scavenger|scavenging]] it, illustrated as such in a painting by [[Charles R. Knight]]. Although notable as the first free-standing mount of a theropod dinosaur and often illustrated and photographed, it has never been scientifically described.<ref name=BBetal99>{{cite journal |last=Breithaupt |first=Brent H. |year=1999 |title=AMNH 5753: The world's first free-standing theropod skeleton |journal=Journal of Vertebrate Paleontology |volume=19 |issue= |page=33A | doi = 10.1080/02724634.1999.10011202}}</ref>

The multiplicity of early names complicated later research, with the situation compounded by the terse descriptions provided by Marsh and Cope. Even at the time, authors such as [[Samuel Wendell Williston]] suggested that too many names had been coined.<ref name=SWW78>{{cite journal |last=Williston |first=Samuel Wendell |year=1878 |title=American Jurassic dinosaurs |journal=Transactions of the Kansas Academy of Science |volume=6 |pages=42–46 |doi=10.2307/3623553 |jstor=3623553 }}</ref> For example, Williston pointed out in [[1901 in paleontology|1901]] that Marsh had never been able to adequately distinguish ''Allosaurus'' from ''Creosaurus''.<ref name=SWW01>{{cite journal |last=Williston |first=Samuel Wendell |year=1901 |title=The dinosaurian genus ''Creosaurus'', Marsh |journal=American Journal of Science |series=Series 4 |volume=11 |issue=62 |pages=111–114 |doi=10.2475/ajs.s4-11.62.111 |url=https://zenodo.org/record/1450114 |bibcode=1901AmJS...11..111W |archive-date=November 9, 2021 |access-date=June 28, 2019 |archive-url=https://web.archive.org/web/20211109012757/https://zenodo.org/record/1450114 |url-status=live }}</ref> The most influential early attempt to sort out the convoluted situation was produced by [[Charles W. Gilmore]] in [[1920 in paleontology|1920]]. He came to the conclusion that the tail vertebra named ''Antrodemus'' by Leidy was indistinguishable from those of ''Allosaurus'' and that ''Antrodemus'' should be the preferred name because, as the older name, it had priority.<ref name=CWG20/> ''Antrodemus'' became the accepted name for this familiar genus for over 50 years, until [[James Henry Madsen]] published on the Cleveland-Lloyd specimens and concluded that ''Allosaurus'' should be used because ''Antrodemus'' was based on material with poor, if any, diagnostic features and locality information. For example, the [[geological formation]] that the single bone of ''Antrodemus'' came from is unknown.<ref name=JM76/> "''Antrodemus''" has been used informally for convenience when distinguishing between the skull Gilmore restored and the composite skull restored by Madsen.<ref name=DH98>{{cite journal |last=Henderson |first=Donald M. |year=1998 |title=Skull and tooth morphology as indicators of niche partitioning in sympatric Morrison Formation theropods |journal=Gaia |volume=15 |pages=219–266 |url=https://www.researchgate.net/publication/228687281}}</ref>

===Cleveland-Lloyd discoveries===
[[File:Allosaurus atrox Cleveland-Lloyd Quarry.jpg|thumb|''A. fragilis'' at the Cleveland-Lloyd Dinosaur Quarry museum, Utah]]
Although sporadic work at what became known as the [[Cleveland-Lloyd Dinosaur Quarry]] in [[Emery County, Utah|Emery County]], Utah, had taken place as early as [[1927 in paleontology|1927]] and the fossil site itself described by [[William Lee Stokes|William L. Stokes]] in [[1945 in paleontology|1945]],<ref name=WJS45>{{cite journal |last=Stokes |first=William L. |year=1945 |title=A new quarry for Jurassic dinosaurs |journal=Science |volume=101 |issue=2614 |pages=115–117 |doi=10.1126/science.101.2614.115-a |pmid=17799203|bibcode = 1945Sci...101..115S |s2cid=13589884 }}</ref> major operations did not begin there until [[1960 in paleontology|1960]]. Under a cooperative effort involving nearly 40&nbsp;institutions, thousands of bones were recovered between 1960 and [[1965 in paleontology|1965]], led by James Henry Madsen.<ref name="JM76"/> The quarry is notable for the predominance of ''Allosaurus'' remains, the condition of the specimens, and the lack of scientific resolution on how it came to be. The majority of bones belong to the large theropod ''Allosaurus fragilis'' (it is estimated that the remains of at least 46&nbsp;''A. fragilis'' have been found there, out of at a minimum 73&nbsp;dinosaurs) and the fossils found there are disarticulated and well-mixed. Nearly a dozen scientific papers have been written on the [[taphonomy]] of the site, suggesting numerous mutually exclusive explanations for how it may have formed. Suggestions have ranged from animals getting stuck in a bog, becoming trapped in deep mud, falling victim to drought-induced mortality around a waterhole, and getting trapped in a spring-fed pond or seep.<ref name="APHetal06">{{cite book |last1=Hunt |first1=Adrian P |last2=Lucas, Spencer G.|last3= Krainer, Karl|last4= Spielmann, Justin |year=2006 |chapter=The taphonomy of the [[Cleveland-Lloyd Dinosaur Quarry]], Upper Jurassic Morrison Formation, Utah: a re-evaluation |editor=Foster, John R. |editor2=Lucas, Spencer G. |title=Paleontology and Geology of the Upper Jurassic Morrison Formation |series=New Mexico Museum of Natural History and Science Bulletin, '''36''' |publisher=New Mexico Museum of Natural History and Science |location=Albuquerque, New Mexico |pages=57–65}}</ref> Regardless of the actual cause, the great quantity of well-preserved ''Allosaurus'' remains has allowed this genus to be known in great detail, making it among the best-known of all theropods. Skeletal remains from the quarry pertain to individuals of almost all ages and sizes, from less than {{convert|1|m|ft|abbr=off}}<ref name="LSCC03"/> to {{convert|12|m|ft|abbr=off}} long, and the disarticulation is an advantage for describing bones usually found fused.<ref name="JM76"/> Due to being one of Utah's two fossil quarries where numerous ''Allosaurus'' specimens have been discovered, ''Allosaurus'' was designated as the [[state fossil]] of Utah in [[1988 in paleontology|1988]].<ref name=statefossil>{{cite web|url=http://pioneer.utah.gov/research/utah_symbols/fossil.html |title=Utah Symbols&nbsp;– State Fossil |access-date=June 16, 2010 |publisher=Pioneer: Utah's Online Library, State of Utah |archive-url=https://web.archive.org/web/20100108021254/http://pioneer.utah.gov/research/utah_symbols/fossil.html |archive-date=January 8, 2010 |url-status=live}}</ref>

===Modern study===
The period since Madsen's monograph has been marked by a great expansion in studies dealing with topics concerning ''Allosaurus'' in life ([[paleobiology|paleobiological]] and [[paleoecology|paleoecological]] topics). Such studies have covered topics including skeletal variation,<ref name=DKS98>{{cite journal |doi=10.1080/02724634.1998.10011039 |last=Smith |first=David K. |year=1998 |title=A morphometric analysis of ''Allosaurus'' |journal=Journal of Vertebrate Paleontology |volume=18 |issue=1 |pages=126–142|bibcode=1998JVPal..18..126S }}</ref> growth,<ref name=PBetal06>{{cite journal |last1=Bybee |first1=Paul J. |year=2006 |title=Sizing the Jurassic theropod dinosaur ''Allosaurus'': Assessing growth strategy and evolution of ontogenetic scaling of limbs |journal=Journal of Morphology |volume=267 |issue=3 |pages=347–359 |doi=10.1002/jmor.10406 |pmid=16380967 |last2=Lee |first2=AH |last3=Lamm |first3=ET|s2cid=35111050 }}</ref><ref name=FC06>{{cite book |last1=Foster |first1=John R. |last2=Chure, Daniel J. |year=2006 |chapter=Hindlimb allometry in the Late Jurassic theropod dinosaur ''Allosaurus'', with comments on its abundance and distribution |editor=Foster, John R. |editor2=Lucas, Spencer G. |title=Paleontology and Geology of the Upper Jurassic Morrison Formation |series=New Mexico Museum of Natural History and Science Bulletin, '''36''' |publisher=New Mexico Museum of Natural History and Science |location=Albuquerque, New Mexico |pages=119–122}}</ref> skull construction,<ref name="ERetal01">{{cite journal |last1=Rayfield |first1=Emily J. |last2=Norman |first2=DB |author-link2=David B. Norman |last3=Horner |first3=CC |last4=Horner |first4=JR |author-link4=Jack Horner (paleontologist) |last5=Smith |first5=PM |last6=Thomason |first6=JJ |last7=Upchurch |first7=P |year=2001 |title=Cranial design and function in a large theropod dinosaur |journal=Nature |volume=409 |issue=6823 |pages=1033–1037 |bibcode=2001Natur.409.1033R |doi=10.1038/35059070 |pmid=11234010 |s2cid=4396729}}</ref> hunting methods,<ref name=BB98>{{cite journal |last=Bakker |first=Robert T. |year=1998 |title=Brontosaur killers: Late Jurassic allosaurids as sabre-tooth cat analogues |journal=Gaia |volume=15 |pages=145–158|issn=0871-5424 |url=https://www.researchgate.net/publication/40662858}}</ref> the brain,<ref name=SWR99>{{cite journal |last=Rogers |first=Scott W. |year=1999 |title=''Allosaurus'', crocodiles, and birds: Evolutionary clues from spiral computed tomography of an endocast |journal=The Anatomical Record |volume=257 |issue=5 |pages=163–173 |doi=10.1002/(SICI)1097-0185(19991015)257:5<162::AID-AR5>3.0.CO;2-W | pmid = 10597341|doi-access=free }}</ref> and the possibility of gregarious living and parental care.<ref name=RTB97>{{cite book |last=Bakker |first=Robert T. |year=1997 |editor=Wolberg, Donald L. |editor2=Sump, Edmund |editor3=Rosenberg, Gary D. |chapter=Raptor Family values: Allosaur parents brought giant carcasses into their lair to feed their young |title=Dinofest International, Proceedings of a Symposium Held at Arizona State University |publisher=Academy of Natural Sciences |location=Philadelphia |pages=51–63|isbn=978-0-935868-94-4}}</ref> Reanalysis of old material (particularly of large 'allosaur' specimens),<ref name=GSP88/><ref name=DJC95>{{cite book |last=Chure |first=Daniel J. |year=1995 |chapter=A reassessment of the gigantic theropod ''Saurophagus maximus'' from the Morrison Formation (Upper Jurassic) of Oklahoma, USA |editor=Ailing Sun |editor2=Yuangqing Wang |title=Sixth Symposium on Mesozoic Terrestrial Ecosystems and Biota, Short Papers |publisher=China Ocean Press |location=Beijing |pages=103–106| isbn=978-7-5027-3898-3}}</ref> new discoveries in Portugal,<ref name=PMetal99>{{cite journal|last1=Pérez-Moreno |first1=B.P. |year=1999 |title=On the presence of ''Allosaurus fragilis'' (Theropoda: Carnosauria) in the Upper Jurassic of Portugal: First evidence of an intercontinental dinosaur species |journal=Journal of the Geological Society |volume=156 |issue=3 |pages=449–452 |doi=10.1144/gsjgs.156.3.0449 |url=http://correio.fc.ul.pt/~cmsilva/Artigos/CMS034.pdf |last2=Chure |first2=D. J. |last3=Pires |first3=C. |last4=Marques Da Silva |first4=C. |last5=Dos Santos |first5=V. |last6=Dantas |first6=P. |last7=Povoas |first7=L. |last8=Cachao |first8=M. |last9=Sanz |first9=J. L. |url-status=dead |archive-url=https://web.archive.org/web/20071025123324/http://correio.fc.ul.pt/~cmsilva/Artigos/CMS034.pdf |archive-date=October 25, 2007 |bibcode=1999JGSoc.156..449P |s2cid=130952546 }}</ref> and several very complete new specimens<ref name=DJC00b/><ref name=BB96>{{cite book |last=Breithaupt |first=Brent |year=1996 |chapter=The discovery of a nearly complete ''Allosaurus'' from the Jurassic Morrison Formation, eastern Bighorn Basin, Wyoming |editor=Brown, C.E. |editor2=Kirkwood, S.C. |editor3=Miller, T.S. |title=Forty-Seventh Annual Field Conference Guidebook |pages=309–313 |publisher=Wyoming Geological Association |location=Casper, Wyoming |oclc=36004754}}</ref><ref name=BigAlTwo>{{cite web |url=http://geo-sciences.com/howequarry.htm |archive-url=https://web.archive.org/web/20071203133129/http://geo-sciences.com/howequarry.htm |archive-date=December 3, 2007 |title=Howe Dinosaur Quarry&nbsp;– Wyoming's Jurassic Treasure |access-date=September 27, 2007 |date=July 24, 2007 |publisher=GeoScience Adventures}}</ref> have also contributed to the growing knowledge base.

==="Big Al" and "Big Al II"===
[[File:Big Al Allosaurus.jpg|left|thumb|"Big Al" ''A. jimmadseni'' skeleton at the [[Museum of the Rockies]]]]
In [[1991 in paleontology|1991]], "Big Al" ([[Museum of the Rockies|MOR]] 693), a 95%&nbsp;complete, partially articulated specimen of ''Allosaurus'' was discovered, measuring about {{convert|8|m}} long. MOR 693 was excavated near [[Shell, Wyoming]], by a joint [[Museum of the Rockies]] and [[University of Wyoming Geological Museum]] team.<ref name=BBbigal>{{cite web|last=Breithaupt |first=Brent H. |url=http://www2.nature.nps.gov/geology/paleontology/pub/fossil_conference_6/breithaupt.htm |title=The case of "Big Al" the ''Allosaurus'': a study in paleodetective partnerships |access-date=October 3, 2007 |archive-url=https://web.archive.org/web/20100107103137/http://nature.nps.gov/geology/paleontology/pub/fossil_conference_6/breithaupt.htm |archive-date=January 7, 2010 |url-status=dead}}</ref> This skeleton was discovered by a Swiss team, led by Kirby Siber. Chure and Loewen in [[2020 in paleontology|2020]] identified the individual as a representative of the species ''A. jimmadseni''. In [[1996 in paleontology|1996]], the same team discovered a second ''Allosaurus'', "Big Al II". This specimen, the best preserved skeleton of its kind to date, is also referred to ''A. jimmadseni''.<ref name=DJC20/>

The completeness, preservation, and scientific importance of this skeleton gave "Big Al" its name. The individual itself was below the average size for ''Allosaurus fragilis'',<ref name=BBbigal/> as it was a subadult estimated at only 87%&nbsp;grown.<ref name=RRH02>{{cite journal |last=Hanna |first=Rebecca R. |year=2002 |title=Multiple injury and infection in a sub-adult theropod dinosaur (''Allosaurus fragilis'') with comparisons to allosaur pathology in the Cleveland-Lloyd Dinosaur Quarry Collection |journal=Journal of Vertebrate Paleontology |volume=22 |issue=1 |pages=76–90 |doi=10.1671/0272-4634(2002)022[0076:MIAIIA]2.0.CO;2 |issn=0272-4634|title-link=Cleveland-Lloyd Dinosaur Quarry |s2cid=85654858 }}</ref> The specimen was described by Breithaupt in 1996.<ref name=BB96/> Nineteen of its bones were broken or showed signs of serious infection, which may have contributed to "Big Al's" death. [[Paleopathology|Pathologic]] bones included five ribs, five vertebrae, and four bones of the feet. Several of its damaged bones showed signs of [[osteomyelitis]], a severe bone infection. A particular problem for the living animal was infection and trauma to the right foot that probably affected movement and may have also predisposed the other foot to injury because of a change in gait. "Big Al" had an infection on the first phalanx on the third toe that was afflicted by an [[involucrum]]. The infection was long-lived, perhaps up to six months.<ref name=RRH02/><ref>{{Cite journal |journal=PaleorXiv |last=Wilkin |first=Jack |date=November 24, 2019 |title=Review of Pathologies on MOR 693: An Allosaurus from the Late Jurassic of Wyoming and Implications for Understanding Allosaur Immune Systems |url=https://osf.io/f3rh6 |doi=10.31233/osf.io/f3rh6|s2cid=242466868 }}</ref> "Big Al II" is also known to have multiple injuries.<ref>{{cite journal | last1 = Foth | first1 = C. | last2 = Evers | first2 = S. | last3 = Pabst | first3 = B. | last4 = Mateus | first4 = O. | last5 = Flisch | first5 = A. | last6 = Patthey | first6 = M. | last7 = Rauhut | first7 = O. W. M. | year = 2015 | title = New insights into the lifestyle of ''Allosaurus'' (Dinosauria: Theropoda) based on another specimen with multiple pathologies | journal = PeerJ | volume = 3 | page = e824v1 | doi=10.7717/peerj.940| pmid = 26020001 | pmc = 4435507 | doi-access = free }}</ref>

===Portuguese discoveries===

[[File:Cliffs of Lourinhã Formation outcrops.png|thumb|right|Cliffs of [[Lourinhã Formation]] outcrops, Portugal]] 
In 1988, during construction works of a warehouse, a skeleton of a large theropod was discovered near the village of Andrés, [[Leiria District]], [[Portugal]].<ref name="PMetal99"/><ref name=":3">{{Cite journal |last1=Malafaia |first1=E. |last2=Ortega |first2=F. |last3=Escaso |first3=F. |last4=Dantas |first4=P. |last5=Pimentel |first5=N. |last6=Gasulla |first6=J. M. |last7=Ribeiro |first7=B. |last8=Barriga |first8=F. |last9=Sanz |first9=J. L. |date=December 10, 2010 |title=Vertebrate fauna at the Allosaurus fossil-site of Andrés (Upper Jurassic), Pombal, Portugal |url=https://revistas.ucm.es/index.php/JIGE/article/view/JIGE1010220193A |journal=Journal of Iberian Geology |language=es |volume=36 |issue=2 |pages=193–204 |doi=10.5209/rev_JIGE.2010.v36.n2.7 |issn=1886-7995|doi-access=free |bibcode=2010JIbG...36..193M }}</ref> The Andrés quarry is included in the Bombarral Formation ("Grés Superiores"). The lower part of this formation is diachronic with the [[Alcobaça Formation]] in the northen [[Lusitanian Basin]], and is dated to the Early [[Tithonian]]. This specimen was reported in 1999 as the first occurrence of ''Allosaurus fragilis'' outside North America.<ref name="PMetal99"/> The specimen, labeled MNHNUL/AND.001, is deposited in the [[National Museum of Natural History and Science, Lisbon]]. It consists of a partial skeleton, composed of an incomplete right quadrate, several vertebrae and chevrons, several dorsal ribs and gastralia, a partial pelvis, most of the hind limbs and several indeterminate fragments.<ref name="PMetal99"/> In 2003, Miguel Telles Antunes and Octávio Mateus published a review of the dinosaurs from Portugal, where they assigned the Andrés specimen to ''Allosaurus'' sp.<ref name=":4">{{Cite journal |last1=Antunes |first1=Miguel Telles |last2=Mateus |first2=Octávio |date=2003 |title=Dinosaurs of Portugal |journal=Palevol |volume=2 |issue=1 |pages=77–95|doi=10.1016/S1631-0683(03)00003-4 |bibcode=2003CRPal...2...77A }}</ref>

The [[Guimarota]] coal mine in [[Leiria District|Leiria]], [[Portugal]], produced plenty of remains of micro-vertebrates while it was being explored.<ref>Martin, T. & Krebs, B. 2000 ''Guimarota. A Jurassic ecosystem.'' Munich: Dr Friedrich Pfeil.</ref> The Guimarota beds belong to the [[Alcobaça Formation]], and are dated of the Late [[Kimmeridgian]]. In 2005, Oliver Rauhut and Regina Fechner describe the right maxilla of a juvenile theropod (IPFUB Gui Th 4) from the [[Guimarota]] mine, that was stored in the collections of the Institute of Geological Sciences of the [[Free University of Berlin]]. They attribute the maxilla to ''Allosaurus'' sp. based on the large maxillary fenestra and coeval presence of the other ''Allosaurus'' specimens.<ref name=":5">{{Cite journal |last1=Rauhut |first1=Oliver W. M |last2=Fechner |first2=Regina |date=June 7, 2005 |title=Early development of the facial region in a non-avian theropod dinosaur |journal=Proceedings of the Royal Society B: Biological Sciences |language=en |volume=272 |issue=1568 |pages=1179–1183 |doi=10.1098/rspb.2005.3071 |issn=0962-8452 |pmc=1559819 |pmid=16024380}}</ref> This specimen allowed the authors to conclude that the development of paranasal pneumacity in theropods is [[Heterochrony|heterochronic]], with juveniles having more pronouced pneumaticity than adults.<ref name=":5"/>

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|footer = ''A. europaeus'' holotype skull with diagram showing preserved elements
}}

In 2006, a new species of ''Allosaurus'', ''A. europaeus'', was reported based a specimen found in a beach near Vale Frades, [[Lourinhã]], [[Portugal]].<ref name="OMetal06">{{cite book |last1=Mateus |first1=Octávio |title=Paleontology and Geology of the Upper Jurassic Morrison Formation |last2=Walen, Aart |last3=Antunes, Miguel Telles |publisher=New Mexico Museum of Natural History and Science |year=2006 |editor=Foster, John R. |series=New Mexico Museum of Natural History and Science Bulletin, '''36''' |location=Albuquerque, New Mexico |pages=123–129 |chapter=The large theropod fauna of the Lourinha Formation (Portugal) and its similarity to that of the Morrison Formation, with a description of a new species of ''Allosaurus'' |editor2=Lucas, Spencer G.}}</ref> The specimen, labeled ML415, is deposited in the [https://museulourinha.org/ Lourinhã Museum], and consists of a partial skull, three cervical vertebrae and cervical ribs. It was found in rocks of the Praia Azul Member of the [[Lourinhã Formation]], which in that sector is dated to the Early [[Tithonian]].<ref>{{Cite journal |last1=Mateus |first1=O. |last2=Dinis |first2=J. |last3=Cunha |first3=P. P. |date=September 30, 2017 |title=The Lourinhã Formation: the Upper Jurassic to lower most Cretaceous of the Lusitanian Basin, Portugal – landscapes where dinosaurs walked |url=http://cienciasdaterra.novaidfct.pt/index.php/ct-esj/article/view/355 |journal=Ciências da Terra - Earth Sciences Journal |volume=19 |issue=1 |pages=75–97 |doi=10.21695/cterra/esj.v19i1.355|hdl=10316/79879 |hdl-access=free }}</ref>

In 2005, the Andrés quarry was reactivated for further prospection, which yielded remains of a diverse vertebrate fauna and new ''Allosaurus'' remains.<ref name="MDOE07">{{cite journal |last1=Malafaia |first1=Elisabete |last2=Dantas, Pedro |last3=Ortega, Francisco |last4=Escaso, Fernando |year=2007 |title=Nuevos restos de ''Allosaurus fragilis'' (Theropoda: Carnosauria) del yacimiento de Andrés (Jurásico Superior; centro-oeste de Portugal) |trans-title=New remains of ''Allosaurus fragilis'' (Theropoda: Carnosauria) of the Andrés deposit (Upper Jurassic; central-west Portugal) |url=http://www.dfmf.uned.es/~fortega/uned_fo_pdf/2007_Malafaia_etal_EJIP07.pdf |url-status=live |journal=Cantera Paleontológica |language=es, en |pages=255–271 |archive-url=https://ghostarchive.org/archive/20221009/http://www.dfmf.uned.es/~fortega/uned_fo_pdf/2007_Malafaia_etal_EJIP07.pdf |archive-date=October 9, 2022}}</ref><ref name=":3"/> These new remains (such as a partial right frontal, MNHNUL/AND.001/062), along with further preparation of the original Andrés specimen, allowed for a more detailed comparison with other ''Allosaurus'' species.<ref name="MDOE07"/> The authors concluded that the Andrés specimen is compatible with the diagnosis of ''A. fragilis'', and also disputed the attribution of the Vale Frades specimen to a new species, claiming that the autapomorphies proposed in the diagnosis of ''A. europaeus'' can be explained by individual variation.<ref name="MDOE07"/> In 2010, new ''Allosaurus'' elements from the Andrés quarry are reported, including new cranial remains such as a right quadrate-quadratojudal, two lacrimals, a right dentary, a right frontal, the posterior end of the right mandible and a complete braincase. A second complete left ilium suggests the presence of a second ''Allosaurus'' individual in the quarry, larger than the first.<ref name=":3"/> The authors once again claim that ''A. europaeus'' should be considered a ''[[nomen dubium]]'' until a more detailed description of the Vale Frades specimen is published.<ref name=":3"/>

A detailed description of the remains of the Andrés specimen was published on the doctoral thesis of Elisabete Malafaia.<ref name=":6">Malafaia, E. (2017). ''Phylogenetic analysis, paleoenvironmental and paleobiogeographic interpretation of theropod dinosaurs from the Upper Jurassic of the Lusitanian Basin'' [Doctoral Thesis, Universidade de Lisboa]. <nowiki>https://repositorio.ulisboa.pt/handle/10451/35031</nowiki></ref> The remains, catalogued as MNHN/UL.AND.#, were collected between 1988 and 2010, and include cranial elements (such as the maxilla, nasal, lacrimals, prefrontal, postorbitals, frontals, palatines, quadrate, quadratojugal, squamosal, vomer, braincase, articular, surangulars, prearticular, angulars, supradentary and coronoid, isolated mesial and lateral teeth) and postcranial elements (intercentrum of the atlas, dorsal, sacral and caudal vertebrae, cervical and dorsal ribs, chevrons, coracoid, ilium, pubes, femora, tibiae, fibulae, astragalus and calcaneum, distal tarsal III, second, third, and fourth metatarsals, and several phalanges).<ref name=":6"/> Duplicate elements reported in the thesis include the previously mentioned left ilium, a fragmentary pubic peduncle in articulation with the pubes, and a right frontal, caudal vertebra, and pedal phalanges of a third much smaller individual. The author claims that the Andrés specimens present noticeable differences with both ''A. fragilis'' and the type specimen of ''A. europaeus'', but tentatively assigns it to ''Allosaurus'' cf. ''europaeus'', pending the discovery of more specimens that allow the comparison between the two.<ref name=":6"/>

In 2024, Burigo and Mateus publish a redescription and revised diagnosis of the Vale Frades specimen.<ref name=":2"/> The authors report new elements, such as the atlas-axis, coronoid, new teeth and rib fragments, and confirm the validity of the species. A specimen-level phylogenetic analysis using scored cranial characters was performed. The authors claim that the Andrés specimen is attributable to ''A. europaeus'', and that ''A. europaeus'' is more closely related to ''A. jimmadsenni'' than to ''A. fragilis''.<ref name=":2"/>

In 2025, Malafaia and colleagues publish a detailed description of the cranial elements of the Andrés specimen in a scientific journal and suggest that ''A. europaeus'' is synonymous with ''A. fragilis''.<ref name=Malafaia2025>{{Cite journal |last=Malafaia |first=Elisabete |last2=Dantas |first2=Pedro |last3=Escaso |first3=Fernando |last4=Mocho |first4=Pedro |last5=Ortega |first5=Francisco |date=2025-05-01 |title=Cranial osteology of a new specimen of Allosaurus Marsh, 1877 (Theropoda: Allosauridae) from the Upper Jurassic of Portugal and a specimen-level phylogenetic analysis of Allosaurus |url=https://doi.org/10.1093/zoolinnean/zlaf029 |journal=Zoological Journal of the Linnean Society |volume=204 |issue=1 |pages=zlaf029 |doi=10.1093/zoolinnean/zlaf029 |issn=0024-4082}}</ref> 

===Species===
[[File:Skulls of Allosaurus species.png|thumb|upright|Diagram comparing skulls of three recognized species; ''A. fragilis'' (A), ''A. jimmadseni'' (B), ''A. europaeus'' (C)]]
Seven species of ''Allosaurus'' have been named: ''A. anax'',<ref name="DEA24"/> ''A. amplus'',<ref>{{cite journal | last1 = Galton | first1 = Peter M. | last2 = Carpenter | first2 = Kenneth | last3 = Dalman | first3 = Sebastian G. | year = 2015 | title = The holotype pes of the Morrison dinosaur ''Camptonotus amplus'' Marsh, 1879 (Upper Jurassic, western USA) – is it ''Camptosaurus'', Sauropoda or ''Allosaurus''? | journal = Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen | volume = 275 | issue = 3| pages = 317–335 | doi = 10.1127/njgpa/2015/0467 |doi-access=free| bibcode = 2015NJGPA.275..317G }}</ref> ''A. atrox'',<ref name=DJC00/> ''A. europaeus'',<ref name=OMetal06/> the [[type species]] ''A. fragilis'',<ref name=HMC04/> ''A. jimmadseni''<ref name=DJC20>{{cite journal |last1=Chure |first1=D.J. |last2=Loewen |first2=M.A. |year=2020 |title=Cranial anatomy of ''Allosaurus jimmadseni'', a new species from the lower part of the Morrison Formation (Upper Jurassic) of Western North America |journal=PeerJ |volume=8 |page=e7803 |doi=10.7717/peerj.7803|pmid=32002317 |pmc=6984342 |doi-access=free }}</ref><ref name=DJC00/> and ''A. lucasi''.<ref>{{cite journal | last1 = Dalman | first1 = Sebastian G. | year = 2014 | title = Osteology of a large allosauroid theropod from the Upper Jurassic (Tithonian) Morrison Formation of Colorado, USA | url = https://vjs.pgi.gov.pl/article/view/26617 | journal = Volumina Jurassica | volume = 12 | issue = 2 | pages = 159–180 | doi = <!-- none --> | archive-date = November 9, 2021 | access-date = September 30, 2020 | archive-url = https://web.archive.org/web/20211109005352/https://vjs.pgi.gov.pl/article/view/26617 | url-status = live }}</ref> Among these (excluding ''A. anax'', which was named in 2024), Daniel Chure and Mark Loewen in 2020 only recognized the species ''A. fragilis'', ''A. europaeus'', and the newly-named ''A. jimmadseni'' as being valid species.<ref name=DJC20/> Some studies have suggested that ''A. europaeus'' does not show any unique characters compared to the North American species,<ref name="MDOE07"/><ref>{{Cite journal |last1=Evers |first1=Serjoscha W. |last2=Foth |first2=Christian |last3=Rauhut |first3=Oliver W.M. |date=February 7, 2020 |title=Notes on the cheek region of the Late Jurassic theropod dinosaur ''Allosaurus'' |journal=PeerJ |volume=8 |pages=e8493 |doi=10.7717/peerj.8493 |issn=2167-8359 |pmc=7008823 |pmid=32076581 |doi-access=free }}</ref><ref name=Malafaia2025/> though other authors have suggested that the species is valid and has a number of distinguishing characters.<ref name=":2">{{Cite journal |last1=Burigo |first1=André |last2=Mateus |first2=Octávio |date=January 2025 |title=''Allosaurus europaeus'' (Theropoda: Allosauroidea) Revisited and Taxonomy of the Genus |journal=Diversity |language=en |volume=17 |issue=1 |pages=29 |doi=10.3390/d17010029 |doi-access=free |issn=1424-2818}}</ref>

''A. fragilis'' is the type species and was named by Marsh in 1877.<ref name=OCM77/> It is known from the remains of at least 60 individuals, all found in the [[Kimmeridgian]]–[[Tithonian]] [[Upper Jurassic]]-age Morrison Formation of the United States, spread across [[Colorado]], [[Montana]], [[New Mexico]], [[Oklahoma]], [[South Dakota]], Utah, and Wyoming.<ref name=HMC04/> Details of the [[humerus]] (upper arm) of ''A. fragilis'' have been used as diagnostic among Morrison theropods,<ref name=JM76/> but ''A. jimmadseni'' indicates that this is no longer the case at the species level.<ref name=DJC00/>

''A. jimmadseni'' has been scientifically described based on two nearly complete skeletons. The first specimen to wear the identification was unearthed in Dinosaur National Monument in northeastern Utah, with the original "Big Al" individual subsequently recognized as belonging to the same species.<ref name=DJC20/><ref name=DJC00/><ref name=DFG03>{{cite book |last=Glut |first=Donald F. |title=Dinosaurs: The Encyclopedia. 3rd Supplement |year=2003 |publisher=McFarland & Co. |location=Jefferson, North Carolina |isbn=978-0-7864-1166-5 |pages=[https://archive.org/details/dinosaursencyclo00glut_2/page/221 221–233] |chapter=Allosaurus |chapter-url=https://archive.org/details/dinosaursencyclo00glut_2 |url=https://archive.org/details/dinosaursencyclo00glut_2/page/221 }}</ref><ref>{{Cite web|url=https://phys.org/news/2020-01-species-allosaurus-utah.html|title=New species of Allosaurus discovered in Utah|website=phys.org|access-date=January 24, 2020|archive-date=November 9, 2021|archive-url=https://web.archive.org/web/20211109005406/https://phys.org/news/2020-01-species-allosaurus-utah.html|url-status=live}}</ref> This species differs from ''A. fragilis'' in several anatomical details, including a [[jugal]] (cheekbone) with a straight lower margin. Fossils are confined to the Salt Wash Member of the Morrison Formation, with ''A. fragilis'' only found in the higher Brushy Basin Member.<ref name=LSCC03>{{cite journal |last1=Loewen |first1=Mark A. |last2=Sampson, Scott D. |last3=Carrano, Matthew T. |last4= Chure, Daniel J. |year=2003 |title=Morphology, taxonomy, and stratigraphy of ''Allosaurus'' from the Upper Jurassic Morrison Formation |journal=Journal of Vertebrate Paleontology |volume=23 |issue=3|page=72A | doi = 10.1080/02724634.2003.10010538 |s2cid=220410105 }}</ref> However, stratigraphic work done by Suzannah Maidment found that both species were actually coeval and were instead segregated by geography, with ''A. fragilis'' mostly found in the southern parts of the Morrison Formation, while ''A. jimmadseni'' is largely found in the northern parts.<ref>{{cite journal |title=Diversity through time and space in the Upper Jurassic Morrison Formation, western U.S.A. |journal=Journal of Vertebrate Paleontology |date=2023 |doi=10.1080/02724634.2024.2326027 |url=https://www.tandfonline.com/doi/full/10.1080/02724634.2024.2326027 |last1=Maidment |first1=Susannah C. R. |volume=43 |issue=5 |url-access=subscription }}</ref> The specific name ''jimmadseni'' is named in honor of Madsen, for his contributions to the taxonomy of the genus, notably for his 1976 work.<ref name="DJC20" />

[[File:Allosaurus anax (holotype, OMNH 1771).png|thumb|left|upright=0.9|Holotype postorbital of ''A. anax'']]
''A. fragilis'', ''A. jimmadseni'', ''A. anax'', ''A. amplus'', and ''A. lucasi'' are all known from remains discovered in the [[Kimmeridgian]]–[[Tithonian]] [[Upper Jurassic]]-age Morrison Formation of the United States, spread across [[Colorado]], [[Montana]], [[New Mexico]], [[Oklahoma]], [[South Dakota]], [[Utah]] and [[Wyoming]]. ''A. fragilis'' is regarded as the most common, known from the remains of at least 60 individuals.<ref name=HMC04/> For a while in the late 1980s and early 1990s, it was common to recognize ''A. fragilis'' as the short-snouted species, with the long-snouted taxon being ''A. atrox.''<ref name=GSP88/><ref name=LG93>{{cite book |last1=Lessem |first1=Don |last2=Glut, Donald F. |year=1993 |title=The Dinosaur Society's Dinosaur Encyclopedia |chapter=Allosaurus |pages=[https://archive.org/details/dinosaursocietys00less/page/19 19–20] |publisher=Random House |isbn=978-0-679-41770-5 |oclc=30361459 |chapter-url=https://archive.org/details/dinosaursocietys00less/page/19 }}</ref> However, subsequent analysis of specimens from the Cleveland-Lloyd Dinosaur Quarry, Como Bluff, and Dry Mesa Quarry showed that the differences seen in the Morrison Formation material could be attributed to individual variation.<ref name=DKS96/><ref name=DKS99/> A study of skull elements from the Cleveland-Lloyd site found wide variation between individuals, calling into question previous species-level distinctions based on such features as the shape of the lacrimal horns and the proposed differentiation of ''A. jimmadseni'' based on the shape of the [[jugal]].<ref name=KC2010/> ''A. anax'' was described and named in 2024 from several fossils representing various skeleton parts, the holotype being a [[postorbital]] numbered as OMNH 1771. This species is characterized by the lack of rugose ornamentation on the postorbital, the dorsal vertebrae with hourglass-shaped centra and [[Skeletal pneumaticity|pneumatic]] foramina, and other features of the postorbital, cervical vertebrae, and [[fibula]]. The specific name comes from the Ancient Greek ἄναξ (''anax'', "king", "lord" or "tribal chief"), and is intended to be an updated reference to the now [[Nomen dubium|dubious]] saurischian genus ''[[Saurophaganax]]'', to which the fossils were previously attributed.<ref name="DEA24">{{Cite journal |last1=Danison |first1=Andrew |last2=Wedel |first2=Mathew |last3=Barta |first3=Daniel |last4=Woodward |first4=Holly |last5=Flora |first5=Holley |last6=Lee |first6=Andrew |last7=Snively |first7=Eric |year=2024 |title=Chimerism in specimens referred to ''Saurophaganax maximus'' reveals a new species of ''Allosaurus'' (Dinosauria, Theropoda) |journal=Vertebrate Anatomy Morphology Palaeontology |language=en |volume=12 |doi=10.18435/vamp29404 |issn=2292-1389 |doi-access=free}}</ref>

The ''Allosaurus'' material from Portugal has a controversial taxonomic research history. The Andrés ''Allosaurus'' specimens, consisting of very complete cranial and post-cranial remains, have been attributed to ''A. fragilis'',<ref name="PMetal99"/><ref>Dantas, P., Pérez-Moreno, B., Chure, D., Silva, C. M. da, Santos, V. F., Póvoas, L., Cachão, M., Sanz, J., Pires, C., Bruno, G., Ramalheiro, G., & Galopim De Carvalho, A. M. (1999). O dinossáurio carnívoro ''Allosaurus fragilis'' no Jurássico superior português. ''Al-Madan'', ''8'', 23–28. <nowiki>https://doi.org/10.13140/RG.2.1.3224.1762</nowiki></ref><ref name="MDOE07"/> ''A.'' sp<ref name=":4"/>'', A. europaeus''<ref name="OMetal06"/> and ''A.'' cf. ''europaeus''.<ref name=":6"/> The Vale Frades ''Allosaurus'', consisting of a partial skull and cervical vertebrae and ribs, is the type specimen of ''A. europaeus'',<ref name="OMetal06"/> although the validity of that species has been previously questioned.<ref name="MDOE07"/><ref name=":3"/> In 2024, a revised diagnosis of ''A. europaeus'' was published, confirming the validity of the species.<ref name=":2"/> The specific affinities of the Andrés specimens are still unclear.

The issue of species and potential synonyms was historically complicated by the [[Type (biology)|type specimen]] of ''Allosaurus fragilis'' ([[Peabody Museum of Natural History|YPM]] 1930) being extremely fragmentary, consisting of a few incomplete vertebrae, limb fragments, rib fragments, and a single tooth. Because of this, several scientists have interpreted the type specimen as potentially dubious, meaning the genus ''Allosaurus'' itself or at least the species ''A. fragilis'' would be a ''nomen dubium'' ("dubious name", based on a specimen too incomplete to compare to other specimens or to classify). To address this situation, [[Gregory S. Paul]] and [[Kenneth Carpenter]] ([[2010 in paleontology|2010]]) submitted a petition to the [[International Commission on Zoological Nomenclature|ICZN]] to have the name ''A. fragilis'' officially transferred to the more complete specimen USNM 4734 (as a [[neotype]]),<ref name="GPKC2010">{{cite journal |last1=Paul |first1=Gregory S. |author-link1=Gregory S. Paul |last2=Carpenter |first2=Kenneth |author-link2=Kenneth Carpenter |year=2010 |title=''Allosaurus'' Marsh, 1877 (Dinosauria, Theropoda): proposed conservation of usage by designation of a neotype for its type species ''Allosaurus fragilis'' Marsh, 1877 |url=http://gspauldino.com/images/BZN67(1)Case3506.pdf |journal=Bulletin of Zoological Nomenclature |volume=67 |issue=1 |pages=53–56 |doi=10.21805/bzn.v67i1.a7 |s2cid=81735811 |archive-date=August 9, 2017 |access-date=September 28, 2018 |archive-url=https://web.archive.org/web/20170809142848/http://gspauldino.com/images/BZN67(1)Case3506.pdf |url-status=live }}</ref> a decision that was ratified by the ICZN on December 29, 2023.<ref>{{cite journal |title=Opinion 2486 (Case 3506) – Allosaurus Marsh, 1877 (Dinosauria, Theropoda): usage conserved by designation of a neotype for its type species Allosaurus fragilis Marsh, 1877 |journal=The Bulletin of Zoological Nomenclature |date=December 2023 |volume=80 |issue=1 |pages=65–68 |doi=10.21805/bzn.v80.a015 |url=https://bioone.org/journals/the-bulletin-of-zoological-nomenclature/volume-80/issue-1/bzn.v80.a015/Opinion-2486-Case-3506--Allosaurus-Marsh-1877-Dinosauria-Theropoda/10.21805/bzn.v80.a015.short |issn=0007-5167|url-access=subscription }}</ref>

Teeth of indeterminate species of ''Allosaurus'' have been reported from Tönniesberg and Kahlberg in [[Saxony]], Germany, dating to the upper Kimmeridigian.<ref name=":2"/>

===Synonyms===
[[File:Creosaurus.jpg|thumb|Holotype material of ''Creosaurus atrox'']]
''Creosaurus'', ''Epanterias'', and ''Labrosaurus'' are provisionally regarded as junior synonyms of ''Allosaurus'',<ref name=HMC04/> though the latter two require new analyses to clarify their specific status.<ref name=":2"/> Most of the species that are regarded as synonyms of ''A. fragilis'', or that were misassigned to the genus, are obscure and based on very scrappy remains. One exception is ''Labrosaurus ferox'', named in [[1884 in paleontology|1884]] by Marsh for an oddly formed partial lower jaw, with a prominent gap in the tooth row at the tip of the jaw, and a rear section greatly expanded and turned down.<ref name=OCM84>{{cite journal |last=Marsh |first=Othniel Charles |year=1884 |title=Principal characters of American Jurassic dinosaurs. Part VIII |journal=American Journal of Science |series=Series 3 |volume=27 |issue=160 |pages=329–340 |doi=10.2475/ajs.s3-27.160.329 |url=https://zenodo.org/record/1450066 |bibcode=1884AmJS...27..329M |s2cid=131076004 |archive-date=December 16, 2021 |access-date=June 28, 2019 |archive-url=https://web.archive.org/web/20211216182115/https://zenodo.org/record/1450066 |url-status=live }}</ref> Later researchers suggested that the bone was [[Pathology|pathologic]], showing an injury to the living animal,<ref name=CWG20/> and that part of the unusual form of the rear of the bone was due to plaster reconstruction.<ref name=MW00>{{cite book |last1=Madsen |first1=James H. |last2=Welles, Samuel P. |title=Ceratosaurus (Dinosauria, Theropoda), a Revised Osteology |year=2000 |series=Miscellaneous Publication, '''00-2''' |publisher=Utah Geological Survey }}</ref> It is now regarded as an example of ''A. fragilis''.<ref name=HMC04/>

In his [[1988 in paleontology|1988]] book, ''Predatory Dinosaurs of the World'', the freelance artist & author Gregory S. Paul proposed that ''A. fragilis'' had tall pointed horns and a slender build compared to a postulated second species ''A. atrox'', as well as not being a [[Sexual dimorphism|different sex]] due to rarity.<ref name=GSP88/> ''Allosaurus atrox'' was originally named by Marsh in [[1878 in paleontology|1878]] as the type species of its own genus, ''Creosaurus'', and is based on YPM 1890, an assortment of bones that includes a couple of pieces of the skull, portions of nine tail vertebrae, two hip vertebrae, an [[Ilium (bone)|ilium]], and ankle and foot bones.<ref name=OCM78/> Although the idea of two common Morrison allosaur species was followed in some semi-technical and popular works,<ref name=LG93/> the [[2000 in paleontology|2000]] thesis on Allosauridae noted that Charles Gilmore mistakenly reconstructed USNM 4734 as having a shorter skull than the specimens referred by Paul to ''atrox'', refuting supposed differences between USNM 4734 and putative ''A. atrox'' specimens like DINO 2560, AMNH 600, and AMNH 666.<ref name=DJC00/>

"Allosaurus agilis", seen in Zittel, [[1887 in paleontology|1887]], and Osborn, [[1912 in paleontology|1912]], is a typographical error for ''A. fragilis.''<ref name=DJC00/> "Allosaurus ferox" is a typographical error by Marsh for ''A. fragilis'' in a figure caption for the partial skull YPM 1893<ref name=OCM96>{{cite journal |last=Marsh |first=Othniel Charles|year=1896 |title=The dinosaurs of North America |journal=United States Geological Survey, 16th Annual Report, 1894–95 |volume=55 |pages=133–244}}</ref> and YPM 1893 has been treated as a specimen of ''A fragilis''.<ref name=HMC04/> Likewise, "Labrosaurus fragilis" is a typographical error by Marsh ([[1896 in paleontology|1896]]) for ''Labrosaurus ferox''.<ref name=MW00/> "A. whitei" is a ''[[nomen nudum]]'' coined by Pickering in 1996 for the complete ''Allosaurus'' specimens that Paul referred to ''A. atrox''.<ref name=DJC00/>

"Madsenius" was coined by [[David Lambert (author)|David Lambert]] in [[1990 in paleontology|1990]],<ref>{{cite web |title=MADSENIUS |url=http://www.dinoruss.com:80/de_4/5a8d03b.htm |website=dinoruss.com |access-date=December 18, 2020 |archive-url=https://web.archive.org/web/20080627012337/http://www.dinoruss.com/de_4/5a8d03b.htm |archive-date=June 27, 2008 |date=March 27, 2006 |url-status=live }}</ref> being based on remains from Dinosaur National Monument assigned to ''Allosaurus'' or ''Creosaurus'' (a synonym of ''Allosaurus''), and was to be described by paleontologist [[Robert T. Bakker|Robert Bakker]] as "Madsenius trux".<ref>Lambert, D. (1990) ''The Dinosaur Data Book'', Facts on File, Oxford, England: 320 pp.</ref> However, "Madsenius" is now seen as yet another synonym of ''Allosaurus'' because Bakker's action was predicated upon the false assumption of USNM 4734 being distinct from long-snouted ''Allosaurus'' due to errors in Gilmore's [[1920 in paleontology|1920]] reconstruction of USNM 4734.<ref name="database">{{cite web |title=Carnosauria |url=https://www.theropoddatabase.com/Carnosauria.htm#Allosaurusfragilis |access-date=December 18, 2020 |website=theropoddatabase.com |archive-date=May 13, 2021 |archive-url=https://web.archive.org/web/20210513103854/https://theropoddatabase.com/Carnosauria.htm#Allosaurusfragilis |url-status=live }}</ref>

"Wyomingraptor" was informally coined by Bakker for [[allosaurid]] remains from the [[Morrison Formation]] of the Late [[Jurassic]]. The remains unearthed are labeled as ''Allosaurus'' and are housed in the Tate Geological Museum. However, there has been no official description of the remains and "Wyomingraptor" has been dismissed as a ''nomen nudum'', with the remains referable to ''Allosaurus''.<ref name=database/><ref>Bakker, 1997. Raptor family values: Allosaur parents brought great carcasses into their lair to feed their young. In Wolberg, Sump and Rosenberg (eds). Dinofest International, Proceedings of a Symposium, Academy of Natural Sciences. 51–63.</ref><ref>{{cite web|url=http://dml.cmnh.org/1997Apr/msg00586.html|title=Re: Raptor question|website=dml.cmnh.org|access-date=January 1, 2019|archive-date=June 24, 2021|archive-url=https://web.archive.org/web/20210624195650/http://dml.cmnh.org/1997Apr/msg00586.html|url-status=dead}}</ref>

===Formerly assigned species and fossils===
[[File:Antrodemus.jpg|thumb|left|''[[Antrodemus]] valens'' holotype tail vertebra (above) compared to the same of ''Allosaurus'' (below)]]
Several species initially classified within or referred to ''Allosaurus'' do not belong within the genus. ''A. medius'' was named by Marsh in 1888 for various specimens from the [[Early Cretaceous]] [[Arundel Formation]] of [[Maryland]],<ref name=OCM88>{{cite journal |last=Marsh |first=Othniel Charles |year=1888 |title=Notice of a new genus of Sauropoda and other new dinosaurs from the Potomac Formation |journal=American Journal of Science |series=Series 3 |volume=35 |issue=205 |pages=89–94 |doi=10.2475/ajs.s3-35.205.89 |url=https://zenodo.org/record/1450082 |bibcode=1888AmJS...35...89M |s2cid=130879860 |archive-date=January 17, 2021 |access-date=June 28, 2019 |archive-url=https://web.archive.org/web/20210117164000/https://zenodo.org/record/1450082 |url-status=live }}</ref> although most of the remains were removed by [[R. S. Lull|Richard Swann Lull]] to the new ornithopod species ''[[Dryosaurus|Dryosaurus grandis]]'', except for a tooth.<ref name=RSL11>{{cite journal |last=Lull |first=Richard Swann | year=1911 |title=The Reptilia of the Arundel Formation |journal=Maryland Geological Survey: Lower Cretaceous |pages=173–178}}</ref> It was transferred to ''Antrodemus'' by Oliver Hay in 1902, but Hay later clarified that this was an inexplicable error on his part.<ref>{{Cite journal |last=Hay |first=Oliver Perry |date=1902 |title=Bibliography and catalogue of the fossil vertebrata of North America |url=https://pubs.er.usgs.gov/publication/b179 |journal=Bulletin |page=23 |doi=10.3133/b179 |bibcode=1902usgs.rept....1H |hdl=2346/65015 |hdl-access=free |archive-date=March 21, 2023 |access-date=March 21, 2023 |archive-url=https://web.archive.org/web/20230321191229/https://pubs.er.usgs.gov/publication/b179 |url-status=live }}</ref><ref>{{Cite journal |last=Hay |first=Oliver Perry |date=1908 |title=On certain genera and species of carnivorous dinosaurs, with special reference to Ceratosaurus nasicornis Marsh |url=http://repository.si.edu/xmlui/handle/10088/14046 |doi=10.5479/si.00963801.35-1648.351 |journal=Proceedings of the United States National Museum|volume=35 |issue=1648|pages=351–366|hdl=10088/14046 }}</ref> Gilmore considered the tooth nondiagnostic but transferred it to ''[[Dryptosaurus]]'', as ''D. medius''.<ref name=CWG20/> The referral was not accepted in the most recent review of basal tetanurans, and ''Allosaurus medius'' was simply listed as a dubious species of theropod.<ref name=HMC04/> It may be closely related to ''[[Acrocanthosaurus]]''.<ref>{{cite web|url=http://theropoddatabase.com/Neotheropoda.htm#Allosaurusmedius|title=Neotheropoda|publisher=The Theropod Database|access-date=September 28, 2018|archive-date=May 24, 2021|archive-url=https://web.archive.org/web/20210524172840/https://theropoddatabase.com/Neotheropoda.htm#Allosaurusmedius|url-status=live}}</ref>

''Allosaurus valens'' is a new combination for ''Antrodemus valens'' used by Friedrich von Huene in 1932;<ref name=DJC00/> ''Antrodemus valens'' itself may also pertain to ''Allosaurus fragilis'',<ref name=HMC04/> as [[Charles W. Gilmore|Gilmore]] suggested in 1920.<ref name=CWG20/>

''A. lucaris'', another Marsh name, was given to a partial skeleton in 1878.<ref name=OCM78/> He later decided it warranted its own genus, ''Labrosaurus'',<ref name=OCM79/> but this has not been accepted, and ''A. lucaris'' is also regarded as another specimen of ''A. fragilis''.<ref name=HMC04/> ''Allosaurus lucaris'', is known mostly from vertebrae, sharing characters with ''Allosaurus''.<ref name="marsh1878">{{cite journal|last=Marsh|first=O.C.|year=1878|title=Notice of new dinosaurian reptiles |url=http://marsh.dinodb.com/marsh/Marsh%201878%20-%20Notice%20of%20new%20dinosaurian%20reptiles.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://marsh.dinodb.com/marsh/Marsh%201878%20-%20Notice%20of%20new%20dinosaurian%20reptiles.pdf |archive-date=October 9, 2022 |url-status=live|journal=American Journal of Science|volume=15 |issue=87 |pages=241–244|doi=10.2475/ajs.s3-15.87.241|bibcode=1878AmJS...15..241M|s2cid=131371457}}</ref> Paul and Carpenter stated that the type specimen of this species, YPM 1931, was from a younger age than ''Allosaurus'', and might represent a different genus. However, they found that the specimen was undiagnostic, and thus ''A. lucaris'' was a ''nomen dubium''.<ref name=GPKC2010/>

''Allosaurus sibiricus'' was described in 1914 by A. N. Riabinin on the basis of a bone, later identified as a partial fourth metatarsal, from the Early Cretaceous of [[Republic of Buryatia|Buryatia]], Russia.<ref name=ANNR14>{{cite journal |last=Riabinin |first=Anatoly Nikolaenvich |year=1914 |title=Zamtka o dinozavry ise Zabaykalya |journal=Trudy Geologichyeskago Muszeyah imeni Petra Velikago Imperatorskoy Academiy Nauk |volume=8 |issue=5 |pages=133–140 |language=ru}}</ref> It was transferred to ''Chilantaisaurus'' in 1990,<ref name=MKD90>{{cite book |last1=Molnar |first1=Ralph E. |last2=Kurzanov, Sergei M. |last3= Dong Zhiming |year=1990 |chapter=Carnosauria |editor=Weishampel, David B. |editor2=Dodson, Peter |editor3=Osmólska, Halszka |title=The Dinosauria |edition=1st |publisher=University of California Press |location=Berkeley |pages=169–209 |isbn=978-0-520-06727-1}}</ref> but is now considered a ''nomen dubium'' indeterminate beyond Theropoda.<ref name=":0">{{cite journal | last1 = Carrano | first1 = Benson | last2 = Sampson | year = 2012 | title = The phylogeny of Tetanurae (Dinosauria: Theropoda) | journal = Journal of Systematic Palaeontology | volume = 10 | issue = 2| pages = 211–300 | doi=10.1080/14772019.2011.630927| bibcode = 2012JSPal..10..211C | s2cid = 85354215 }}</ref>

''Allosaurus meriani'' was a new combination by George Olshevsky for ''[[Megalosaurus]] meriani'' Greppin, 1870, based on a tooth from the Late Jurassic of Switzerland.<ref name=JG70>{{cite journal |last=Greppin |first=J.B. |year=1870 |title=Description geologique du Jura bernois et de quelques districts adjacents |journal=Beiträge zur Geologischen Karte der Schweiz |volume=8 |pages=1–357 |language=fr}}</ref><ref>Olshevsky, 1978. The archosaurian taxa (excluding the Crocodylia). Mesozoic Meanderings. 1, 1–50.</ref> However, a recent overview of ''Ceratosaurus'' included it in ''Ceratosaurus'' sp.<ref name=MW00/>

''[[Apatodon|Apatodon mirus]]'', based on a scrap of vertebra Marsh first thought to be a mammalian jaw, has been listed as a synonym of ''Allosaurus fragilis''.<ref>Olshevsky, G., 1991, A revision of the parainfraclass Archosauria Cope, 1869, excluding the advanced Crocodylia. Mesozoic Meanderings 2, 196 pp</ref><ref name=DFG97/> However, it was considered indeterminate beyond Dinosauria by Chure,<ref name=DJC00/> and Mickey Mortimer believes that the synonymy of ''Apatodon'' with ''Allosaurus'' was due to correspondence to Ralph Molnar by John McIntosh, whereby the latter reportedly found a paper saying that Othniel Charles Marsh admitted that the ''Apatodon'' holotype was actually an allosaurid dorsal vertebra.<ref>{{cite web|url=http://theropoddatabase.com/Non-theropods.htm#Apatodonmirus|title=Apatodonmirus|publisher=The Theropod Database|access-date=September 28, 2018|archive-date=May 18, 2021|archive-url=https://web.archive.org/web/20210518161057/https://theropoddatabase.com/Non-theropods.htm#Apatodonmirus|url-status=live}}</ref>

[[File:Clash of Titans Saurophaganax and Apatosaurus.jpg|thumb|upright|Mounted skeletons showing ''[[Saurophaganax]]'' as an ''Allosaurus''-like taxon attacking ''[[Apatosaurus]]'' sp., in [[Oklahoma Museum of Natural History]]. The latter dinosaur may be closer to the actual identity of ''Saurophaganax'', and the former instead represents ''A. anax'']]
''A. amplexus'' was named by [[Gregory S. Paul]] for giant Morrison allosaur remains, and included in his conception ''Saurophagus maximus'' (later ''Saurophaganax'').<ref name=GSP88/> ''A. amplexus'' was originally coined by Cope in 1878 as the type species of his new genus ''[[Epanterias]]'',<ref name=EDC78>{{cite journal |last=Cope |first=Edward Drinker |year=1878 |title=A new opisthocoelous dinosaur |journal=American Naturalist |volume=12 |issue=6 |pages=406–408 |doi=10.1086/272127|doi-access=free }}</ref> and is based on what is now AMNH 5767, parts of three vertebrae, a [[coracoid]], and a metatarsal.<ref name=OM21>{{cite journal |last1=Osborn |first1=Henry Fairfield |author-link1=Henry Fairfield Osborn |last2=Mook, Charles C. |year=1921 |title=''Camarasaurus'', ''Amphicoelias'', and other sauropods of Cope |journal=Memoirs of the American Museum of Natural History |series=New Series |volume=3 |issue=1 |pages=247–387 |bibcode=1919GSAB...30..379O |doi=10.1130/GSAB-30-379 |hdl=2027/mdp.39015042532476 |hdl-access=free }}</ref> Following Paul's work, this species has been accepted as a synonym of ''A. fragilis''.<ref name=HMC04/> A 2010 neotype designation by Greogry S. Paul and Kenneth Carpenter, however, suggested that ''Epanterias'' holotype is temporally younger than the ''A. fragilis'' type specimen, and that it is not the same taxon as the ''Allosaurus'' holotype.<ref name=GPKC2010/>

''A. maximus'' was a new combination by David K. Smith for Chure's ''Saurophaganax maximus'', a taxon created by Chure in 1995 for giant allosaurid remains from the Morrison of Oklahoma. These remains had been known as ''Saurophagus'', but that name was already in use, leading Chure to propose a substitute.<ref name=DJC95/> Smith, in his 1998 analysis of variation, concluded that ''S. maximus'' was not different enough from ''Allosaurus'' to be a separate genus, but did warrant its own species, ''A. maximus''.<ref name=DKS98/> This reassignment was rejected in a review of basal tetanurans.<ref name=HMC04/> A 2024 reassessment of fossil material assigned to ''Saurophaganax'' suggested that the holotype neural arch of this taxon could not confidently be assigned to a theropod, but that it exhibited some similarities to sauropods. Other ''Saurophaganax'' bones could be referred to diplodocid sauropods. As such, the researchers assigned the remaining theropod bones to a new species of ''Allosaurus'', ''A. anax''.<ref name="DEA24"/>

There are also several species left over from the synonymizations of ''Creosaurus'' and ''Labrosaurus'' with ''Allosaurus''. ''[[Capitalsaurus|Creosaurus potens]]'' was named by Lull in 1911 for a vertebra from the Early Cretaceous of Maryland.<ref name=RSL11/> It is now regarded as a dubious theropod.<ref name=HMC04/> ''Labrosaurus stechowi'', described in 1920 by Janensch based on isolated ''Ceratosaurus''-like teeth from the Tendaguru beds of Tanzania,<ref name=WJ20>{{cite journal |last=Janensch |first=Werner |year=1920 |title=Uber ''Elaphrosaurus bambergi'' und die Megalosaurier aus den Tendaguru-Schichten Deutsch-Ostafricas |journal=Sitzungsberichte Gesellschaft Naturforschender Freunde Berlin |volume=8 |pages=225–235}}</ref> was listed by [[Donald F. Glut]] as a species of ''Allosaurus'',<ref name=DFG97/> is now considered a dubious ceratosaurian related to ''[[Ceratosaurus]]''.<ref name=MW00/><ref name=TR04>Tykoski, Ronald S.; and Rowe, Timothy. (2004). "Ceratosauria", in ''The Dinosauria'' (2nd). 47–70.</ref> ''L. sulcatus'', named by Marsh in 1896 for a Morrison theropod tooth,<ref name=OCM96/> which like ''L. stechowi'' is now regarded as a dubious ''Ceratosaurus''-like ceratosaur.<ref name=MW00/><ref name=TR04/>

[[File:Allosaurus tendagurensis.jpg|thumb|left|''A. tendagurensis'' tibia, Naturkunde Museum Berlin]]
''A. tendagurensis'' was named in 1925 by [[Werner Janensch]] for a partial [[Tibia|shin]] (MB.R.3620) found in the Kimmeridgian-age [[Tendaguru Formation]] in [[Mtwara Region|Mtwara]], Tanzania.<ref name=WJ25>{{cite journal |last=Janensch |first=Werner |year=1925 |title=Die Coelurosaurier und Theropoden der Tendaguru-Schichten Deutsch-Ostafrikas |journal=Palaeontographica |issue=Suppl. 7 |volume=1 |pages=1–99 |language=de }}</ref> Although tabulated as a tentatively valid species of ''Allosaurus'' in the second edition of the Dinosauria,<ref name=HMC04/> subsequent studies place it as indeterminate beyond Tetanurae, either a carcharodontosaurian or megalosaurid.<ref name=OWMR05>{{cite journal |last=Rauhut |first=Oliver W.M. |year=2005 |title=Post-cranial remains of 'coelurosaurs' (Dinosauria, Theropoda) from the Late Jurassic of Tanzania |journal=Geological Magazine |volume=142 |issue=1 |pages=97–107 |doi=10.1017/S0016756804000330 |bibcode=2005GeoM..142...97R |s2cid=131517482 |url=http://edoc.hu-berlin.de/18452/22460 }}</ref><ref name=OR2011>{{cite journal |last=Rauhut |first=Oliver W. M. |title=Theropod dinosaurs from the Late Jurassic of Tendaguru (Tanzania) |journal=Special Papers in Palaeontology |volume=86 |pages=195–239 }}</ref> Although obscure, it was a large theropod, possibly around {{convert|10|m}} long and {{convert|2.5|t|}} in weight.<ref name=MMDML03/>

Kurzanov and colleagues in 2003 designated six teeth from Siberia as ''Allosaurus'' sp. (meaning the authors found the specimens to be most like those of ''Allosaurus'', but did not or could not assign a species to them).<ref name=KEG03>{{cite journal |last1=Kurzanov |first1=Sergei S. |last2=Efimov, Mikhail B. |last3= Gubin, Yuri M. |year=2003 |title=New archosaurs from the Jurassic of Siberia and Mongolia |journal=Paleontological Journal |volume=37 |issue=1 |pages=53–57}}</ref> They were reclassified as an indeterminate theropod.<ref name=":0"/> Also, reports of ''Allosaurus'' in [[Shanxi]], China go back to at least 1982.<ref name=DFG82>{{cite book |last=Glut |first=Donald F. |title=The New Dinosaur Dictionary |year=1982 |publisher=Citadel Press |location=Secaucus, NJ |isbn=978-0-8065-0782-8 |page=[https://archive.org/details/newdinosaurdicti00glut/page/44 44] |url=https://archive.org/details/newdinosaurdicti00glut/page/44 }}</ref> These were interpreted as ''[[Torvosaurus]]'' remains in 2012.<ref name=":0"/>

An [[Talus bone|astragalus]] (ankle bone) thought to belong to a species of ''Allosaurus'' was found at [[Cape Paterson, Victoria]] in Early Cretaceous beds in southeastern Australia. It was thought to provide evidence that Australia was a [[Refugium (population biology)|refugium]] for animals that had gone extinct elsewhere.<ref name=MFR81>{{cite journal |last1=Molnar |first1=Ralph E. |last2=Flannery, Timothy F. |last3= Rich, Thomas H.V. |year=1981 |title=An allosaurid theropod dinosaur from the Early Cretaceous of Victoria, Australia |journal=Alcheringa |volume=5 |pages=141–146 |doi=10.1080/03115518108565427 |issue=2 |bibcode=1981Alch....5..141M }}</ref> This identification was challenged by [[Samuel Paul Welles|Samuel Welles]], who thought it more resembled that of an [[Ornithomimidae|ornithomimid]],<ref name=SPW83>{{cite journal |last=Welles |first=Samuel P. |year=1983 |title=''Allosaurus'' (Saurischia, Theropoda) not yet in Australia |journal=Journal of Paleontology |volume=57 |issue=2 |page=196 }}</ref> but the original authors defended their identification.<ref name=MFR85>{{cite journal |last1=Molnar |first1=Ralph E. |last2=Flannery, Timothy F. |last3= Rich, Thomas H.V. |year=1985 |title=Aussie ''Allosaurus'' after all |journal=Journal of Paleontology |volume=59 |issue=6 |pages=1511–1535  }}</ref> With fifteen years of new specimens and research to look at, Daniel Chure reexamined the bone and found that it was not ''Allosaurus'', but could represent an allosauroid.<ref name=DJC98>{{cite journal |last=Chure |first=Daniel J. |year=1998 |title=A reassessment of the Australian ''Allosaurus'' and its implications for the Australian refugium concept |journal=Journal of Vertebrate Paleontology |volume=18 |issue=3, Suppl |pages=1–94 | doi = 10.1080/02724634.1998.10011116}}</ref> Similarly, Yoichi Azuma and [[Phil Currie]], in their description of ''[[Fukuiraptor]]'', noted that the bone closely resembled that of their new genus.<ref name=AC00>{{cite journal |last1=Azuma |first1=Yoichi |last2=Currie, Philip J. |year=2000 |title=A new carnosaur (Dinosauria: Theropoda) from the Lower Cretaceous of Japan |journal=Journal of Vertebrate Paleontology |volume=37 |issue=12 |pages=1735–1753 |doi=10.1139/e00-064 |bibcode=2000CaJES..37.1735A |url=http://doc.rero.ch/record/14299/files/PAL_E1450.pdf |archive-date=April 29, 2023 |access-date=January 3, 2023 |archive-url=https://web.archive.org/web/20230429154614/https://doc.rero.ch/record/14299/files/PAL_E1450.pdf |url-status=live }}</ref> This specimen is sometimes referred to as "[[List of informally named dinosaurs#Allosaurus robustus|Allosaurus robustus]]", an informal museum name.<ref name=DFG03/> It likely belonged to something similar to ''[[Australovenator]]'',<ref name=SHetal09>{{cite journal |last1=Hocknull |first1=Scott A. |last2=White, Matt A. |last3=Tischler, Travis R. |last4=Cook, Alex G. |last5=Calleja, Naomi D. |author6=Sloan, Trish |author7= Elliott, David A. |year=2009 |title=New Mid-Cretaceous (Latest Albian) Dinosaurs from Winton, Queensland, Australia |journal=PLOS ONE |volume=4 |issue=7 |doi=10.1371/journal.pone.0006190 |pages=e6190 |pmid=19584929 |pmc=2703565 |editor1-last=Sereno |editor1-first=Paul|bibcode=2009PLoSO...4.6190H |doi-access=free }}</ref> although one study considered it to belong to an [[abelisaur]].<ref name=agnolinetal2010>{{cite journal |last1=Agnolin |first1=F. L. |last2=Ezcurra, M. D. |last3=Pais, D. F. |last4= Salisbury, S. W. |year=2010 |title=A reappraisal of the Cretaceous non-avian dinosaur faunas from Australia and New Zealand: Evidence for their Gondwanan affinities |journal=Journal of Systematic Palaeontology |volume=8 |issue=2 |pages=257–300 |doi=10.1080/14772011003594870|bibcode=2010JSPal...8..257A |s2cid=130568551 |url=https://espace.library.uq.edu.au/view/UQ:206067/UQ206067.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://espace.library.uq.edu.au/view/UQ:206067/UQ206067.pdf |archive-date=October 9, 2022 |url-status=live }}</ref>