Editing Carcharodontosaurus

{{short description|Genus of carcharodontosaurid dinosaur from the Cretaceous period}}
{{good article}}
{{Use American English|date=October 2024}}
{{Use mdy dates|date=February 2025}} 
{{automatic taxobox
| fossil_range = [[Late Cretaceous]] ([[Cenomanian]]), {{Fossil range|100|94}}
| image = Ultimate Dinosaurs Carcharodontosaurus.jpg
| image_caption = Reconstructed ''C. saharicus'' skull, [[Science Museum of Minnesota]]
| image_alt = Reconstructed skull of a carcharodontosaurid theropod dinosaur
| taxon = Carcharodontosaurus
| authority = [[Ernst Stromer von Reichenbach|Stromer]], [[1931 in paleontology|1931]]
| type_species = {{extinct}}'''''Carcharodontosaurus saharicus'''''
| type_species_authority = ([[Charles Depéret|Depéret]] & [[Justin Savornin|Savornin]], [[1925 in paleontology|1925]])<br/> [originally ''[[Megalosaurus]]'']
| subdivision_ranks = Other species
| subdivision = * {{extinct}}'''''C. iguidensis?'''''<br/><small>[[Steve Brusatte|Brusatte]] & [[Paul Sereno|Sereno]], [[2007 in paleontology|2007]]</small>
| synonyms = {{collapsible list|bullets = true
|''[[Megalosaurus]] saharicus'' <small>Depéret & Savornin, 1925</small>
|''[[Dryptosaurus]] saharicus'' <small>(Depéret & Savornin, 1925)</small>
|''Megalosaurus africanus'' <small>von Huene, [[1956 in paleontology|1956]]</small> }}
}}

'''''Carcharodontosaurus''''' ({{IPAc-en|ˌ|k|ɑːr|k|ər|oʊ-|ˌ|d|ɒ|n|t|oʊ-|ˈ|s|ɔːr|ə|s}}; {{lit|shark toothed lizard}}) is a genus of large [[Carnivore|carnivorous]] [[theropod]] [[dinosaur]] that lived in [[Maghreb|Northwest Africa]] from about 100 to 94 million years ago during the [[Cenomanian]] age of the [[Cretaceous]]. Two [[teeth]] of the genus, now lost, were first described from Algeria by French [[paleontologists]] [[Charles Depéret]] and [[Justin Savornin]] as ''[[Megalosaurus]] saharicus''. A partial skeleton initially referred to this genus was collected by crews of German paleontologist [[Ernst Stromer]] during a 1914 expedition to Egypt. Stromer did not report the Egyptian find until 1931, in which he dubbed the novel genus ''Carcharodontosaurus'', making the type species '''''C.&nbsp;saharicus'''''. Although this skeleton was destroyed during the [[World War II|Second World War]], it was subsequently redescribed as the holotype of a distinct carcharodontosaurid genus, ''[[Tameryraptor]]''. In 1995, a nearly complete [[skull]] of ''C. saharicus,'' the first well-preserved specimen to be found in almost a century, was discovered in the [[Kem Kem Group|Kem Kem Beds]] of Morocco, which was officially designated as the [[neotype]] in 2007. In the same year, fossils unearthed from the [[Echkar Formation]] of northern Niger were described and named as another species, '''''C. iguidensis''''', though this species might belong to a different genus.

''Carcharodontosaurus'' is one of the largest theropod dinosaurs known, with the type species reaching {{cvt|12–12.5|m|abbr=on}} in length and approximately {{convert|5|-|7|MT|ST}} in body mass. It had a large, lightly built [[skull]] with a triangular [[Rostrum (anatomy)|rostrum]]. Its [[jaw]]s were lined with sharp, recurved, serrated teeth that bear striking resemblances to those of the [[great white shark]] (genus ''[[Carcharodon]]''), the inspiration for the name. Though giant, its cranium was made lighter by greatly expanded [[Fossa (anatomy)|fossae]] and [[Antorbital fenestra|fenestrae]], but also making it more fragile than [[Tyrannosauridae|tyrannosaurids']]. Studies of the [[Bite force quotient|bite force]] and tooth anatomy of carcharodontosaurids have found them to have relatively low bite force compared to other (large) theropods. The [[forelimb]]s were tiny whereas the [[hindlimb]]s were robust and muscular. Like most other theropods, it had an elongated [[tail]] for balance. Many gigantic theropods are known from North Africa during this period, including both species of ''Carcharodontosaurus'' as well as the [[Spinosauridae|spinosaurid]] ''[[Spinosaurus]]'', the possible [[ceratosaur]] ''[[Deltadromeus]],'' and unnamed large [[abelisaurid]]s. North Africa at the time was blanketed in [[mangrove]] forests and [[wetland]]s, creating a hotspot of [[fish]], [[crocodyliforms]], and [[pterosaur]] diversity.

==Discovery and species==
=== Initial finds ===
[[File:Lost holotype teeth of Carcharodontosaurus saharicus.png|thumb|left|250x250px|Lost original teeth of ''C. saharicus'' (Fig. 1-2), the [[lectotype]] being at the top (Fig. 1)]]
In 1924, two teeth of ''Carcharodontosaurus'' were unearthed from wall cuts in different [[Qanat|foggaras]] near [[Timimoun]], [[French Algeria]]. These sediments came from the [[Cretaceous]]-aged<ref name=":14">{{Cite journal |last1=Benyoucef |first1=Madani |last2=Pérez-García |first2=Adán |last3=Bendella |first3=Mohamed |last4=Ortega |first4=Francisco |last5=Vullo |first5=Romain |last6=Bouchemla |first6=Imad |last7=Ferré |first7=Bruno |date=2022 |title=The 'mid'-Cretaceous (Lower Cenomanian) Continental Vertebrates of Gara Samani, Algeria. Sedimentological Framework and Palaeodiversity |journal=Frontiers in Earth Science |volume=10 |page=927059 |doi=10.3389/feart.2022.927059 |bibcode=2022FrEaS..10.7059B |doi-access=free }}</ref> [[Continental intercalaire|Continental intercalaire Formation]].<ref name=":3">{{Cite journal |last1=Depéret |first1=Charles |last2=Savornin |first2=Justin |date=1927 |title=La faune de reptiles et de poisons albiens de Timimoun (Sahara algérien) |journal=Bulletin de la Société Géologique de France |volume=27 |pages=257–265 |url=https://patrimoine.sorbonne-universite.fr/viewer/2708/?offset=#page=293&viewer=picture&o=&n=0&q=}}</ref> The fossils were taken to the governor of Timimoun, Captain Burté, who gave them to French geologist [[Charles Depéret]] later that year. In 1925, Depéret and his colleague [[Justin Savornin]] [[Species description|described]] the teeth as coming of a new species of [[Theropoda|theropod]] dinosaur, ''[[Megalosaurus]] saharicus''. These were the first fossils of theropods to be described from the region. The [[specific name]] ''saharicus'' refers to the [[Sahara|Sahara Desert]] where the teeth had been found.<ref>{{Cite journal |last1=Depéret |first1=Charles |last2=Savornin |first2=Justin |date=1925 |title=Sur la découverte d'une faune de vertébrés albiens à Timimoun (Sahara occidental) |url=https://gallica.bnf.fr/ark:/12148/bpt6k3134w/f1108.item.r=saharicus |journal=Comptes Rendus de l'Académie des Sciences |volume=181 |pages=1108–1111}}</ref> The genus ''Megalosaurus'' was a [[wastebasket taxon]], with many new species referred to it without justification, including ''M.&nbsp;saharicus''.<ref>{{Cite journal |last1=Benson |first1=Roger B. J. |last2=Barrett |first2=Paul M. |last3=Powell |first3=H. Philip |last4=Norman |first4=David B. |date=2008 |title=The taxonomic status of ''Megalosaurus bucklandii'' (Dinosauria, Theropoda) from the Middle Jurassic of Oxfordshire, UK |journal=Palaeontology |volume=51 |issue=2 |pages=419–424 |doi=10.1111/j.1475-4983.2008.00751.x |bibcode=2008Palgy..51..419B |s2cid=83324840 |doi-access=free }}</ref> It was later considered to be a species of ''[[Dryptosaurus]]'' in 1927,<ref name=":3" /> though this is unjustified.<ref name=":4">{{Cite book|last=von Huene|first=Friedrich|year=1956|title=Palaeontologie und Phylogenie der Niederen Tetrapoden|publisher=VEB Gustav Fischer Verlang|volume=1|place=[[Jena]]|pages=716|oclc=489883421}}</ref><ref name=":5">{{Cite journal |last1=Sereno |first1=Paul C. |last2=Dutheil |first2=Didier B. |last3=Iarochene |first3=M. |last4=Larsson |first4=Hans C. E. |last5=Lyon |first5=Gabrielle H. |last6=Magwene |first6=Paul M. |last7=Sidor |first7=Christian A. |last8=Varricchio |first8=David J. |last9=Wilson |first9=Jeffrey A. |year=1996 |title=Predatory Dinosaurs from the Sahara and Late Cretaceous Faunal Differentiation |journal=Science |volume=272 |issue=5264 |pages=986–991 |doi=10.1126/science.272.5264.986 |pmid=8662584 |bibcode=1996Sci...272..986S |s2cid=39658297 |url=http://doc.rero.ch/record/13893/files/PAL_E831.pdf |archive-date=December 4, 2024 |access-date=March 20, 2024 |archive-url=https://web.archive.org/web/20241204204501/https://doc.rero.ch/record/13893/files/PAL_E831.pdf |url-status=live }}</ref> By accident, another species of ''Megalosaurus, M. africanus'', was named by [[Germany|German]] paleontologist [[Friedrich von Huene]] based on the teeth.<ref name=":4" /> It is therefore considered a [[Synonym (taxonomy)|junior synonym]] of ''M. saharicus''.<ref name="Mortimer 2023 Carnosauria"/> Both syntypic teeth of ''M. saharicus'' have since been lost, possibly being kept in a collection in Algeria, [[Paris]], or [[Lyon]], and lack distinguishing characteristics from other [[Carcharodontosauridae|carcharodontosaurids]].<ref name=":6">{{Cite journal |last1=Brusatte |first1=Stephen L. |last2=Sereno |first2=Paul C. |date=December 12, 2007 |title=A new species of ''Carcharodontosaurus'' (Dinosauria: Theropoda) from the Cenomanian of Niger and a revision of the genus |journal=Journal of Vertebrate Paleontology |volume=27 |issue=4 |pages=902–916 |doi=10.1671/0272-4634(2007)27[902:ANSOCD]2.0.CO;2 |s2cid=86202969 }}</ref> In 1960, French paleontologist [[Albert-Félix de Lapparent]] reported the discovery of more teeth and several caudal vertebrae from sites in Algeria belonging to ''Carcharodontosaurus'',<ref name=":2">{{Cite journal |last=de Lapparent |first=Albert |date=1960 |title=Les dinosauriens du "Continental intercalaire" du Sahara central. |url=https://naturalhistory.si.edu/sites/default/files/media/translated_publications/Lapparent_60.pdf |journal=Memoirs of the Geological Society of France |volume=88A |pages=1–57}}</ref> though some of these fossils might belong to other genera.<ref name="Mortimer 2023 Carnosauria"/> Later authors mentioned finds of teeth and isolated fossils from other provinces of Algeria.<ref>{{Cite journal|author1=Gabani, A. |author2=Mammeri, C. |author3=Adaci, M. |author4=Bensalah, M. |author5=Mahboubi, M. |date=2016 |title=Le Crétacé continental à vertébrés de la bordure sud du Plateau de Tinhert: considérations stratigraphiques et bilan paléontologique |journal=Mémoire du Service Géologique de l'Algérie |volume=19 |pages=39–61}}</ref><ref name=":14" />

[[File:Tameryraptor_(holotype,_SNSB-BSPG_1922_X_46).png|thumb|238x238px|Prior April 1944 photo of the partial skeleton described by [[Ernst Stromer]] in 1931, now the holotype of ''[[Tameryraptor]]'']]

However, a partial skeleton later referred to ''C. saharicus'' was first found in marls near [[Bahariya Oasis|Ain Gedid]], Egypt, in early April 1914 by [[Austria-Hungary|Austro-Hungarian]] paleontologist [[Richard Markgraf]]. Marls from this region derive from the [[Cenomanian]]-aged [[Bahariya Formation]], one of many Cretaceous-aged sites of [[North Africa]].<ref name=":8">{{Cite journal |last1=Stromer |first1=Ernst |date=1931 |title=Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltier-Reste der Baharîjestufe (unterstes Cenoman). 10. Ein Skelett-Rest von ''Carcharodontosaurus'' nov. gen. |trans-title=Results of Prof. E. Stromer's research trips in the deserts of Egypt. II. Vertebrate remains from the Baharîje stage (lower Cenomanian). 10. A skeletal remains of ''Carcharodontosaurus'' nov. gen. |journal=Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematisch-naturwissenschaftliche Abteilung |series=Neue Folge |language=de |volume=9 |pages=1–31|url=https://www.dinochecker.com/papers/Stromers-Egypt-expedition_Carcharodontosaurus_Stromer_1931.pdf|translator-last1=Carrano|translator-first1=Matthew}}</ref><ref name=":5" />{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=162}} In this formation, Markgraf did extensive collecting of dinosaur skeletons for his employer, German paleontologist [[Ernst Stromer]] of the [[Paläontologisches Museum München]] (Bavarian State Collection of Paleontology).<ref name=":8"/> Due to [[World War I|political tensions]] between the [[German Empire]] and then [[History of Egypt under the British|British-owned Egypt]], this skeleton, since numbered as SNSB-BSPG 1922 X 46, took years to get to Germany. It was not until 1922 that they were transported overseas to [[Munich]] where they were described by Stromer in 1931.{{sfn|Nothdurft|Smith|2002|p=107–108}} Stromer recognized that the skeleton's teeth would match the characteristic dentition of those described by Depéret and Savornin, which led to Stromer conserving the species name ''saharicus.'' However, he found it necessary to erect a new genus for this species, ''Carcharodontosaurus'', for their similarities, in sharpness and serrations, to the teeth of the [[great white shark]] (''Carcharodon carcharias'').<ref name=":8" /> In his 1931 and 1934 descriptions, Stromer designates the smaller of the two teeth originally described by Depéret and Savornin as the [[type specimen]] (name-bearing specimen) of the [[taxon]].<ref name=":8" />{{sfn|Stromer|1934|p=62}} Thus, this tooth, although lost, must be considered as the [[lectotype]] of ''C. saharicus''.<ref name=Tameryraptor/> [[World War II]] would break out in 1939, leading SNSB-BSPG 1922 X 46 and other material from Bahariya to be destroyed during a [[Bombing of Munich in World War II|British bombing raid on Munich]] during the night of April 24/25, 1944.<ref>{{Cite journal |last1=Smith |first1=Joshua B. |last2=Lamanna |first2=Matthew C. |last3=Mayr |first3=Helmut |last4=Lacovara |first4=Kenneth J. |date=2006 |title=New information regarding the holotype of Spinosaurus aegyptiacus Stromer, 1915 |journal=Journal of Paleontology |volume=80 |issue=2 |pages=400–406 |doi=10.1666/0022-3360(2006)080[0400:NIRTHO]2.0.CO;2 |s2cid=130989487 }}</ref>{{sfn|Nothdurft|Smith|2002|p=117}} An [[endocast]] was made and survived the war, being the only remaining relic of the specimen.{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=162, 164}} However in 2025, this specimen was redescribed as the holotype of a distinct carcharodontosaurid genus, ''[[Tameryraptor]]''.<ref name=Tameryraptor/>

=== Resurgent discoveries, ''C. iguidensis'', and confusion with spinosaurids ===
Few discoveries of ''Carcharodontosaurus'' attributed material were made until 1995 when [[United States|American]] paleontologist [[Paul Sereno]] found an incomplete skull during an expedition embarked on by the [[University of Chicago]]. This skull (SGM-Din 1) was found in the Cenomanian-aged rocks of the [[Kem Kem Group|Lower Douira Formation, Kem Kem Beds]], in [[Errachidia Province|Errachidia]], southeastern Morocco. The specimen was taken to the University of Chicago and was first described in 1996 by Sereno and colleagues in ''[[Science (journal)|Science]]''.<ref name=":5"/> In 2007, SGM-Din 1 was officially designated as the [[neotype]] of ''C. saharicus'' due to the loss of other specimens and the similar age and geographic location to previously noted material.<ref name=":6"/> The taxonomy of ''Carcharodontosaurus'' was discussed by Chiarenza and Cau (2016),<ref name="ChiarenzaandCau2016">{{Cite journal |last1=Chiarenza |first1=Alfio Alessandro |last2=Cau |first2=Andrea |date=February 29, 2016 |title=A large abelisaurid (Dinosauria, Theropoda) from Morocco and comments on the Cenomanian theropods from North Africa |journal=PeerJ |volume=4 |pages=e1754 |doi=10.7717/peerj.1754 |pmc=4782726 |pmid=26966675 |doi-access=free }}</ref> who suggested that the neotype of ''C. saharicus'' was similar but distinct from the skeleton described by Stromer in the morphology of the maxillary interdental plates. However, paleontologist [[Mickey Mortimer]] put forward that the suggested difference between the two specimens was actually due to damage to the neotype.<ref name="Mortimer 2023 Carnosauria">{{Cite web |last=Mortimer |first=Mickey |date=2023 |title=Carnosauria |url=https://theropoddatabase.com/Carnosauria.htm#Carcharodontosaurussaharicus |url-status=live |archive-url=https://web.archive.org/web/20230528042437/https://theropoddatabase.com/Carnosauria.htm |archive-date=May 28, 2023 |access-date=June 6, 2023 |website=The Theropod Database}}</ref> Because the neotype designation was in accordance with the [[ICZN]] article 75.3 and 75.4, the describers of ''Tameryraptor'' agreed that SGM-Din 1 is a valid neotype.<ref name=Tameryraptor>{{cite journal |last1=Kellermann |first1=Maximilian |last2=Cuesta |first2=Elena |last3=Rauhut |first3=Oliver W. M. |title=Re-evaluation of the Bahariya Formation carcharodontosaurid (Dinosauria: Theropoda) and its implications for allosauroid phylogeny |journal=PLOS ONE |date=January 14, 2025 |volume=20 |issue=1 |pages=e0311096 |doi=10.1371/journal.pone.0311096|doi-access=free |pmid=39808629 |pmc=11731741 |bibcode=2025PLoSO..2011096K }}</ref>

Several other fossils of ''C. saharicus'' have been unearthed from the Kem Kem Beds, such as [[Mandible|dentary]] fragments, a [[Cervical vertebrae|cervical vertebra]], and many teeth.<ref name=":0">{{Cite journal |last=Russell |first=Dale |date=1996 |title=Isolated Dinosaur bones from the Middle Cretaceous of the Tafilalt, Morocco |url=https://sciencepress.mnhn.fr/fr/periodiques/bulletin-du-museum-national-d-histoire-naturelle-4eme-serie-section-c-sciences-de-la-terre-paleontologie-geologie-mineralogie/18/2-3/os-isoles-de-dinosaures-du-cretace-moyen-du-tafilalt-maroc |journal=Bulletin du Muséum national d'Histoire naturelle, 4ème série – section C – Sciences de la Terre, Paléontologie, Géologie, Minéralogie |language=fr |volume=18 |issue=2–3}}</ref><ref>{{cite book |last1=Gheerbrant |first1=Emmanuel |last2=Cappetta |first2=Henri |last3=Broin |first3=F. de Lapparent de |last4=Rage |first4=Jean Claude |last5=Tabuce |first5=Rodolphe |title=Mémoires de la société géologique de France |date=2017 |publisher=Société Géologique de France |isbn=978-2-85363-099-3 |pages=485–525 |chapter-url=https://mnhn.hal.science/mnhn-02264868/ |language=fr |chapter=Les faunes de vertébrés marins et terrestres du Paléogène du Bassin d'Ouarzazate, Maroc }}</ref>{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=167}} Sereno et al. also referred a multitude of [[cervical vertebrae]] described as the [[Spinosauridae|spinosaurids]] ''[[Sigilmassasaurus]]'' and "''Spinosaurus'' B" to ''C. saharicus'' reasoning that stout cervicals would be needed to carry the skulls of carcharodontosaurids.<ref name=":6" /><ref name=":5" /> Later research proved otherwise, with the vertebrae being placed in ''[[Spinosaurus aegyptiacus]]'' by Ibrahim et al. (2020).{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=169}} French paleontologist [[René Lavocat]] was the first to note the possible presence of ''Carcharodontosaurus'' in Morocco as early as 1954.<ref>{{Cite journal |last=Lavocat |first=Rene |date=1954 |title=Sur les dinosauriens du Continental Intercalaire des Kem-Kem de la Daoura |journal=Comptes Rendus 19th International Geological Congress |volume=1952 |pages=65–68}}</ref>

In 2007, a novel species of ''Carcharodontosaurus, C. iguidensis,'' was dubbed by paleontologists [[Stephen L. Brusatte|Steve Brusatte]] and Paul Sereno. Fossils of ''C. iguidensis'' had been uncovered during an expedition to the [[Echkar Formation]] of Iguidi, Niger, a partial [[maxilla]] (MNN IGU2) being designated the holotype. The species name ''iguidensis'' is after Iguidi, where the fossils were unearthed. Several other remains such as a braincase, a lacrimal, a dentary, a cervical vertebra, and a collection of teeth were referred to ''C. iguidensis'' based on size and supposed similarities to other ''Carcharodontosaurus'' bones.<ref name=":6"/> Chiarenza and Cau (2016) identified the referred material of ''C. iguidensis'' as belonging to ''Sigilmassasaurus'' (later referred to ''Spinosaurus'' sp.)<ref>{{Cite journal |last1=Sereno |first1=Paul C. |last2=Myhrvold |first2=Nathan |last3=Henderson |first3=Donald M. |last4=Fish |first4=Frank E. |last5=Vidal |first5=Daniel |last6=Baumgart |first6=Stephanie L. |last7=Keillor |first7=Tyler M. |last8=Formoso |first8=Kiersten K. |last9=Conroy |first9=Lauren L. |date=November 30, 2022 |editor-last=Zhu |editor-first=Min |editor2-last=Rutz |editor2-first=Christian |editor3-last=Zhu |editor3-first=Min |editor4-last=Holtz |editor4-first=Thomas R. |editor5-last=Hone |editor5-first=David |title=''Spinosaurus'' is not an aquatic dinosaur |journal=eLife |volume=11 |pages=e80092 |doi=10.7554/eLife.80092 |pmc=9711522 |pmid=36448670 |doi-access=free }}</ref> and a non-[[Carcharodontosaurinae|carcharodontosaurine]], and therefore chose to limit ''C. iguidensis'' to the holotype pending future research.<ref name="ChiarenzaandCau2016" /> Another carcharodontosaurid from the Kem Kem Beds, ''[[Sauroniops|Sauroniops pachytholus]]'', was dubbed in 2012 based on a single [[Frontal lobe|frontal]],<ref name=":10">{{Cite journal |last1=Cau |first1=Andrea |last2=Dalla Vecchia |first2=Fabio M. |last3=Fabbri |first3=Matteo |date=March 1, 2013 |title=A thick-skulled theropod (Dinosauria, Saurischia) from the Upper Cretaceous of Morocco with implications for carcharodontosaurid cranial evolution |journal=Cretaceous Research |volume=40 |pages=251–260 |doi=10.1016/j.cretres.2012.09.002 |bibcode=2013CrRes..40..251C }}</ref> and has been proposed to be synonymous with ''C. saharicus''.{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=171}} This proposed synonymy has been disputed by others.<ref>{{Cite journal |last1=Candeiro |first1=Carlos Roberto dos Anjos |last2=Brusatte |first2=Stephen Louis |last3=Vidal |first3=Luciano |last4=Pereira |first4=Paulo Victor Luiz Gomes da Costa |date=July 26, 2018 |title=Paleobiogeographic evolution and distribution of Carcharodontosauridae (Dinosauria, Theropoda) during the middle Cretaceous of North Africa |journal=Papéis Avulsos de Zoologia |volume=58 |pages=e20185829 |doi=10.11606/1807-0205/2018.58.29 |s2cid=53353652 |hdl=20.500.11820/c4ca0a5c-4f8e-4136-8355-8bd32d6ea544 |hdl-access=free }}</ref><ref name="ChiarenzaandCau2016" /><ref name=":1">{{Cite journal |last1=Paterna |first1=Alessandro |last2=Cau |first2=Andrea |date=October 11, 2022 |title=New giant theropod material from the Kem Kem Compound Assemblage (Morocco) with implications on the diversity of the mid-Cretaceous carcharodontosaurids from North Africa |journal=Historical Biology |volume=35 |issue=11 |pages=2036–2044 |doi=10.1080/08912963.2022.2131406 |s2cid=252856791 }}</ref><ref name="Cau&Paterna25" /> The South American genus ''[[Giganotosaurus]]'' was synonymized with ''Carcharodontosaurus'' by Figueiredo (1998)<ref>{{Cite news |last=Figueiredo |date=1998 |title=Os dinossáurios carnívoros: A sua descrição e modo de vida |pages=1–4 |work=Centro Portugues de Geo-historia e Prehistoria}}</ref> and [[Gregory S. Paul|Paul]] (2010),<ref name="G.S.Paul2016">{{Cite book |last=Paul |first=Gregory S. |url=http://worldcat.org/oclc/985402380 |title=The Princeton Field Guide to Dinosaurs |publisher=Princeton University Press |year=2016 |isbn=978-1-78684-190-2 |pages=103–104 |oclc=985402380 |author-link=Gregory S. Paul}}</ref> but no authors have since followed this assessment.<ref name=":17" /><ref name=":6" />

==== Other referred specimens ====
{{location map+|Africa|relief=yes|width=300|float=|caption=Fossil localities of ''Carcharodontosaurus''
Legend: [[File:Steel pog.svg|8px]] ''C. saharicus'' [[File:Red pog.svg|8px]] ''C. iguidensis'' [[File:Orange_pog.svg|8px]] Possible specimens|places={{location map~ | Africa| label =Continental Interclaire Formation | position = none | lat=27.0333| long=1.0833| mark= Steel pog.svg}}
{{location map~ | Africa| label =Kem Kem Beds | position = none | lat=31.5317| long=-4.6656| mark= Steel pog.svg}}
{{location map~ | Africa| label =Douiret Formation | position = none | lat=32.691| long= 10.261| mark= Steel pog.svg}}
{{location map~ | Africa| label =Continental Interclaire Formation (type locality) | position = none | lat=29.25| long= 0.25| mark= Steel pog.svg}}
{{location map~ | Africa| label =Continental Interclaire Formation | position = none | lat=28.369| long=  9.381| mark= Steel pog.svg}}
{{location map~ | Africa| label =Gara Samani Formation | position = none | lat=32.7022| long= -0.0067| mark= Steel pog.svg}}
{{location map~ | Africa| label = Elrhaz Formation | position = none | lat=16.1292| long=10.222| mark= Orange_pog.svg}}
{{location map~ | Africa| label = Echkar Formation| position = none | lat=17.9333| long=  5.6167| mark= Red pog.svg}}|alt=Map of sites preserving Carcharodontosaurus.}}

* Lapparent (1951, 1960) described several ''Carcharodontosaurus'' teeth from the Continental intercalaire Formation of [[Tataouine Governorate|Guermessa, Tunisia]].<ref name=":2" /><ref name=":16">{{cite journal|last1=Buffetaut|first1=Éric|last2=Ouaja|first2=Mohamed|title=A new specimen of ''Spinosaurus'' (Dinosauria, Theropoda) from the Lower Cretaceous of Tunisia, with remarks on the evolutionary history of the Spinosauridae|journal=Bulletin de la Société géologique de France|year=2002|volume=173|issue=5|pages=415–421|doi=10.2113/173.5.415|s2cid=53519187|url=https://doc.rero.ch/record/14728/files/PAL_E1854.pdf}}</ref>
* A [[postorbital bone]] and several postcranial remains assigned to ''Carcharodontosaurus'' were found in the [[Elrhaz Formation]] of northern Niger. Taquet (1976) noted that the postorbital was similar to that of ''Acrocanthosaurus,'' a relative of  ''Carcharodontosaurus'',{{sfn|Taquet|1976|p=53}} while the postcranial fossils could belong to other theropods.<ref name="Mortimer 2023 Carnosauria"/><ref name="Tameryraptor" />
* Two braincase fragments, 137 teeth, two caudal vertebrae, and a manual phalanx from the Echkar Formation were referred to as ''Carcharodontosaurus'' by Lapparent (1960).<ref name=":2" /> A pedal phalanx had also been described as ''Carcharodontosaurus'' but it likely is from a spinosaurid instead.<ref>{{Cite journal |last1=Ibrahim |first1=Nizar |last2=Sereno |first2=Paul C. |last3=Dal Sasso |first3=Cristiano |last4=Maganuco |first4=Simone |last5=Fabbri |first5=Matteo |last6=Martill |first6=David M. |last7=Zouhri |first7=Samir |last8=Myhrvold |first8=Nathan |last9=Iurino |first9=Dawid A. |date=September 26, 2014 |title=Semiaquatic adaptations in a giant predatory dinosaur |journal=Science |volume=345 |issue=6204 |pages=1613–1616 |doi=10.1126/science.1258750 |pmid=25213375 |bibcode=2014Sci...345.1613I |s2cid=34421257 |doi-access=free }}</ref>
* Many vertebrae, including two associated dorsals, were found in the [[Early Cretaceous]] strata of the [[Irhazer Shale|Irhazer Group]] of [[Agadez Region|Agadez]], Niger. Lapparent mentioned these fossils as ''C. saharicus'' in 1960,<ref name=":2" /> though they may belong to other theropod genera.<ref name="Mortimer 2023 Carnosauria"/>
* Caudal vertebrae from the Tefidet and teeth from Akarazeras sites of the Continental intercalaire Formation of Agadez, Niger were recorded by Lapparent (1960)<ref name=":2" /> and Taquet (1976) respectively.{{sfn|Taquet|1976|p=53}} The vertebrae could be from other theropods.<ref name="Mortimer 2023 Carnosauria"/>
* From an unknown locale in the Continental intercalaire of the Sahara Desert, Lapparent (1960) documented eight vertebrae, a humerus, and a manual phalanx as coming from ''C. saharicus.''<ref name=":2" /> These elements could be from other theropods.<ref name="Mortimer 2023 Carnosauria"/>
* Teeth and a caudal vertebra from the [[Chenini Member|Chenini Formation]] of southern [[Tunisia]] have been referred to ''Carcharodontosaurus''.<ref name="Schlüter Schwarzhans 1978">{{cite journal |last1=Schlüter |first1=T |last2=Schwarzhans |first2=W |date=1978 |title=Eine Bonebed-Lagerstätte aus dem Wealden Süd Tunesiens (Umgebung Ksar Krerachfa) |journal=Berliner Geowiss. Abhandlungen A |volume=8 |pages=53–65 }}</ref> However, the caudal vertebra is now labeled Carcharodontosauridae indet.<ref name="Fanti Cau Martinelli Contessi 2014">{{cite journal |last1=Fanti |first1=Federico |last2=Cau |first2=Andrea |last3=Martinelli |first3=Agnese |last4=Contessi |first4=Michela |title=Integrating palaeoecology and morphology in theropod diversity estimation: A case from the Aptian-Albian of Tunisia |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |date=September 2014 |volume=410 |pages=39–57 |doi=10.1016/j.palaeo.2014.05.033 |bibcode=2014PPP...410...39F }}</ref>
* In 2015, a large [[neural arch]] of a [[Thoracic vertebrae|dorsal vertebra]] from the Kem Kem Beds was informally described as belonging to a new genus and species of [[megaraptora]]n dubbed "Osteoporosia gigantea". This specimen is owned by the head of a Polish theme park chain who described it as belonging to a {{Convert|15|m|ft}} long carnosaur similar to ''[[Mapusaurus]]'' and ''Carcharodontosaurus.''<ref>{{Cite web |last=Singer |date=2015 |title=JuraPark na tropie nowych dinozaurow z Maroka. |url=https://jurapark.pl/jurapark-na-tropie-nowych-dinozaurow-z-maroka/ |url-status=live |archive-url=https://web.archive.org/web/20151206224352/https://jurapark.pl/jurapark-na-tropie-nowych-dinozaurow-z-maroka/ |archive-date=December 6, 2015 |access-date=June 27, 2023 |website=Jurapark}}</ref> However, it was much smaller than proposed and may belong to ''C. saharicus'' or ''Sauroniops'' based on its carcharodontosaurid traits and origin.<ref>{{Cite book |last1=Molina-Pérez |first1=Rubén |title=Dinosaur Facts and Figures: The Theropods and Other Dinosauriformes |last2=Larramendi |first2=Asier |last3=Connolly |first3=David |last4=Cruz |first4=Gonzalo Ángel Ramírez |date=2019 |publisher=Princeton University Press |isbn=978-0-691-19059-4 }}{{pn|date=October 2024}}</ref>

==== Previously assigned specimens ====

* A maxillary tooth recovered from the [[Villar del Arzobispo Formation]] of [[Spain]] was referred to ''Carcharodontosaurus'' in 1966.<ref>{{cite journal|language=es|first1=M.|last1=Crusafont-Pairó|first2=R.|last2=Adrover|year=1966|title=El primer representante de la clase mamíferos hallado en el Mesozoico de España|journal=Teruel|volume=35|pages=139–143}}</ref> However, it lacks the traits of carcharodontosaurid teeth and instead is more similar to that of other [[Allosauroidea|allosauroids]].<ref>{{Cite journal |last1=Kuhne |first1=W. G. |last2=Crusafont-Pairo |first2=M. |date=1968 |title=Mamíferos del Wealdiense de Uña, cerca de Cuenca |url=https://www.raco.cat/index.php/ActaGeologica/article/download/74602/97493 |journal=Acta Geológica Hispánica |volume=3 |issue=5 |pages=133–134}}</ref><ref>{{Cite journal |last1=Gascó |first1=Francisco |last2=Cobos |first2=Alberto |last3=Royo-Torres |first3=Rafael |last4=Mampel |first4=Luis |last5=Alcalá |first5=Luis |date=June 1, 2012 |title=Theropod teeth diversity from the Villar del Arzobispo Formation (Tithonian–Berriasian) at Riodeva (Teruel, Spain) |journal=Palaeobiodiversity and Palaeoenvironments |volume=92 |issue=2 |pages=273–285 |doi=10.1007/s12549-012-0079-3 |bibcode=2012PdPe...92..273G |s2cid=129930988 }}</ref>
* Bond and Bromley (1970) described teeth deriving from the [[Gokwe Formation]] of [[Zimbabwe]] as being similar to ''Carcharodontosaurus'', with Mickey Mortimer assigning them to the genus tentatively.<ref>{{Cite journal |last1=Bond |first1=Geoffrey |last2=Bromley |first2=K. |date=December 1970 |title=Sediments with the remains of dinosaurs near Gokwe, Rhodesia |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=8 |issue=4 |pages=313–327 |bibcode=1970PPP.....8..313B |doi=10.1016/0031-0182(70)90104-5 |s2cid=128716797 }}</ref> However, later studies have found them to be indeterminate.<ref>{{Cite journal|author1=Munyikwa, D.|author2=Sampson, S. D.|author3=Rogers, R. R.|author4=Forster, C. A. |author5=Curry, K. A. |author6=Curtice, B. D. |date=1998 |title=Vertebrate palaeontology and geology of the Gokwe Formation, Zimbabwe |journal=Journal of African Earth Sciences |volume=27 |issue=1 |pages=142}}</ref>
* Teeth from the [[Alcântara Formation|Alcantara Formation]] of [[Brazil]] were placed in ''Carcharodontosaurus'' in 2002,<ref>{{Cite journal |last1=Medeiros |first1=Manuel |last2=Schultz |first2=Cesar |date=2002 |title=A fauna dinossauriana da 'Laje do Coringa', Cretaceo medio de Nordeste do Brasil |id={{BHL page|57292482}} |journal=Arquivos do Museo Nacional, Rio de Janeiro |volume=60 |issue=3 |pages=155–162 }}</ref> but this has been disputed based on its geographic origin.<ref name="Mortimer 2023 Carnosauria"/>
* Partial specimens from [[Wadi Milk Formation]] were originally assigned to ''Carcharodontosaurus'', but were now considered to be indeterminate carcharodontosaurids, some of which are similar to the genus.<ref name="Mortimer 2023 Carnosauria"/>
* Fossils from the [[Campanian]] [[Quseir Formation]] of western Egypt have been tentatively assigned to ''Spinosaurus'' and ''Carcharodontosaurus'',<ref name=Churcher1999>{{cite book |last1=Churcher |first1=C. S. |chapter=A note on the Late Cretaceous vertebrate fauna of the Dakhleh Oasis |pages=55–68 |editor1-last=Churcher |editor1-first=C. S. |editor2-last=Mills |editor2-first=Anthony J. |title=Reports from the Survey of the Dakhleh Oasis, Western Desert of Egypt, 1977-1987 |date=1999 |publisher=Oxbow Books |isbn=978-1-900188-49-4 }}</ref> but these specimens were never described in detail and thus classified as [[Theropoda]] indet.<ref>{{cite book|last1=Augustin|first1=F.J.|last2=Hartung|first2=J.|last3=Kampouridis|first3=P.|editor1=Hamimi, Z.|editor2=Khozyem, H.|editor3=Adatte, T.|editor4=Nader, Fadi H.|editor5=Oboh-Ikuenobe, F.|editor6=Zobba, Mohamed K.|editor7=Atfy, Haytham El|year=2023|chapter=Dinosaur Faunas of Egypt—The Terrestrial Late Cretaceous Vertebrate Record|title=The Phanerozoic Geology and Natural Resources of Egypt|pages=253–284|series=Advances in Science, Technology & Innovation|publisher=Springer, Cham|doi=10.1007/978-3-030-95637-0_9|isbn=978-3-030-95636-3}}</ref>

==Description==
=== Size ===
[[File:Longest theropods.svg|thumb|left|upright=1.7|alt=Size comparison of the largest theropods.|Size comparison of giant [[theropods]], ''C. saharicus'' in orange, far right]]

Stromer hypothesized that ''C. saharicus'' was around the same size as the [[Tyrannosauridae|tyrannosaurid]] ''[[Gorgosaurus]]'', which would place it at around {{convert|8|-|9|m}} long, based on his specimen SNSB-BSPG 1922 X 46 (now ''[[Tameryraptor]]''). This individual was around 15% smaller than the neotype,{{Sfn|Nothdurft|Smith|2002|p=109}} the latter was estimated to be {{convert|12|-|12.5|m}} in length and approximately {{convert|5|-|7|MT|ST}} in body mass.<ref name="Henderson&Nicholls2015">{{cite journal |last1=Henderson |first1=D.M. |last2=Nicholls |first2=R. |year=2015 |title=Balance and Strength—Estimating the Maximum Prey-Lifting Potential of the Large Predatory Dinosaur ''Carcharodontosaurus saharicus'' |journal=The Anatomical Record |volume=298 |issue=8 |pages=1367–1375 |doi=10.1002/ar.23164 |pmid=25884664 |s2cid=19465614|doi-access=free }}</ref><ref name="G.S.Paul2016" /><ref name="seebacher2001">{{cite journal |last1=Seebacher |first1=Frank |title=A new method to calculate allometric length-mass relationships of dinosaurs |journal=Journal of Vertebrate Paleontology |date=March 26, 2001 |volume=21 |issue=1 |pages=51–60 |doi=10.1671/0272-4634(2001)021[0051:ANMTCA]2.0.CO;2 }}</ref><ref>{{Cite book |title=Tyrannosaurid Paleobiology |last1=Hurlburt |first1=G. S. |last2=Ridgely |first2=R. C. |last3=Witmer |first3=L. M. |date=July 5, 2013 |publisher=Indiana University Press |isbn=978-0-253-00947-0 |editor-last=Parrish |editor-first=M. J. |pages=134–154 |chapter=Relative size of brain and cerebrum in Tyrannosaurid dinosaurs: an analysis using brain-endocast quantitative relationships in extant alligators |access-date=October 20, 2013 |editor-last2=Molnar |editor-first2=R. E. |editor-last3=Currie |editor-first3=P. J. |editor-last4=Koppelhus |editor-first4=E. B. |chapter-url=https://www.researchgate.net/publication/256536375}}</ref> This makes ''Carcharodontosaurus saharicus'' one of the largest known theropod dinosaurs and one of the largest terrestrial carnivores.<ref name=":17" /><ref name="G.S.Paul2016" /> ''C. iguidensis'' was much smaller, only reaching {{convert|10|m}} in length and {{convert|4|MT|ST}} in body mass.<ref name="G.S.Paul2016" />

=== Skull ===
==== Cranium and teeth ====
[[File:Carcharodontosaurus_saharicus_skull_reconstruction.png|thumbnail|Reconstructed skull of ''C. saharicus'', showing known material in white|237x237px|alt=Diagram of the skull of C. saharicus]]
The largest and most complete skull of ''C. saharicus'' would measure {{Convert|1.6|m|ft}} when complete, around the same size as the largest ''[[Tyrannosaurus]]'' skulls. No skulls of the genus preserve [[premaxilla]]e, complete posterior skull regions, or [[mandible]]s. Skulls of carcharodontosaurids tend to be more slender and lightly built than those of later tyrannosaurids, which have robust builds and adaptations for crushing. The neotype cranium tapers towards the front in side view creating a triangular outline. This is similar to that of other carcharodontosaurids like ''Mapusaurus'' and ''Giganotosaurus''. Its skull was lighter than that of tyrannosaurids, with the [[antorbital fenestra]] composing over 30% of the total skull length as well as being surrounded by {{Dinogloss|fossae}} in the [[maxilla]]e (upper jaw bone), [[Nasal bone|nasals]] (nose bone), [[Jugal bone|jugals]] (cheekbone), and [[Lacrimal bone|lacrimals]] (front orbit bone). Akin to other genera, its nasal is elongated and its exposed side is covered in a rugose surface. These bumps were likely extended by [[keratin]] sheaths, creating a horn-like structure as in ''[[Ceratosaurus]]''. A similar rugosity is found on the lacrimal which would also be lengthened by keratin, forming a similar element.{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=165}}<ref name=":5" /> The most distinctive trait of ''Carcharodontosaurus''{{'}} skull is the sculpted exterior of the maxillae, which is unique to the genus. ''C. iguidensis'' has antorbital fossae limited to the proximity of the antorbital fenestra, a crest running along the [[Anatomical terms of location|medial]] (right) face of the maxilla, and a [[process (anatomy)|process]] along its midline. These traits are missing in ''C. saharicus'', differentiating the two species.<ref name=":6" />

{{multiple image
| align             = left
| total_width       = 240
| perrow            = 2/2
| image1            = Right maxilla of Carcharodontosaurus.jpg
| alt1              = Right maxilla of C. saharicus
| image2            = Carcharodontosaurus nasal and lacrimal bone.jpg
| alt2              = Nasal and lacrimal of C. saharicus
| image3            = Carcharodontosaurus jugal bones.jpg
| alt3              = Jugals of C. saharicus
| image4            = Carcharodontosaurus postorbital bones.jpg
| alt4              = Postorbitals of C. saharicus
| footer            = Skull bones of the neotype specimen; right maxilla (upper left), nasal and lacrimal (upper right), jugals (lower left), and postorbitals (lower right)
}}

14 teeth sockets are present in each maxilla. Parts of the braincase are known though much of their morphology is the same as ''Giganotosaurus''{{'}}. However, ''C. saharicus'' has a much more prominent [[Nuchal lines|nuchal crest]], which overhangs the skull roof. The frontal bones are firmly fused, a characteristic evident in most theropods.<ref>{{cite journal |last1=Coria |first1=Rodolfo A. |last2=Currie |first2=Philip J. |title=The braincase of Giganotosaurus carolinii (Dinosauria: Theropoda) from the Upper Cretaceous of Argentina |journal=Journal of Vertebrate Paleontology |date=January 14, 2003 |volume=22 |issue=4 |pages=802–811 |doi=10.1671/0272-4634(2002)022[0802:TBOGCD]2.0.CO;2 }}</ref> The jugals are broad and triangle-shaped. The [[Joint|lower jaw articulation]] was placed farther back behind the [[occipital condyle]] (where the neck is attached to the skull) compared to other theropods.<ref name=":5" /> Two dentary (lower jaw bone) fragments which were referred to ''C. saharicus'' by Ibrahim et al. (2020) have deep and expanded [[Dental alveolus|alveoli]] (tooth sockets), traits found in other large theropods.<ref name=":0" />{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=167}} If like ''[[Tyrannotitan]]'' and ''Giganotosaurus'', the dentary would have 16 alveoli (tooth sockets).<ref name=":11">{{Cite journal |last1=Novas |first1=Fernando E. |last2=de Valais |first2=Silvina |last3=Vickers-Rich |first3=Pat |last4=Rich |first4=Tom |date=May 1, 2005 |title=A large Cretaceous theropod from Patagonia, Argentina, and the evolution of carcharodontosaurids |journal=Naturwissenschaften |volume=92 |issue=5 |pages=226–230 |doi=10.1007/s00114-005-0623-3 |pmid=15834691 |bibcode=2005NW.....92..226N |hdl=11336/103474 |s2cid=24015414 |hdl-access=free }}</ref>

Estimations of the tooth count of ''Carcharodontosaurus'' vary, but a recent estimate of 30 dentary, 8 premaxillary, and 24 maxillary teeth for a total of 62 teeth was made.<ref name=":12">{{Cite journal |last1=Beevor |first1=Thomas |last2=Quigley |first2=Aaron |last3=Smith |first3=Roy E. |last4=Smyth |first4=Robert S. H. |last5=Ibrahim |first5=Nizar |last6=Zouhri |first6=Samir |last7=Martill |first7=David M. |date=January 1, 2021 |title=Taphonomic evidence supports an aquatic lifestyle for Spinosaurus |journal=Cretaceous Research |volume=117 |pages=104627 |doi=10.1016/j.cretres.2020.104627 |bibcode=2021CrRes.11704627B |s2cid=224888268 |url=https://researchportal.port.ac.uk/portal/en/publications/taphonomic-evidence-supports-an-aquatic-lifestyle-for-spinosaurus(e7fb2358-2ac6-4b6c-9697-225a525e8366).html }}</ref> Carcharodontosaurid teeth are some of the largest of any dinosaur group, with a maxillary tooth from SNSB-BSPG 1922 X 46 being {{Convert|6.8|cm|in}} tall and {{Convert|3.5|cm|in}} wide.<ref name=":8" /><ref>{{Cite web |title=Discoveries {{!}} Paul Sereno - Paleontologist {{!}} The University of Chicago |url=https://paulsereno.uchicago.edu/discoveries/carcharodontosaurus/#:~:text=Carcharodontosaurus%20is%20Africa%27s%20answer%20to,-inch-long%20serrated%20teeth. |access-date=June 30, 2023 |website=paulsereno.uchicago.edu}}</ref> However, they are extremely thin, with most being under a centimeter thick. Serrations are numerous on the anterior and posterior margins, with over 18 to 20 serrations per centimeter of edge in ''C. saharicus'' and up to 32 per centimeter in ''C. iguidensis''.<ref name=":6" /><ref name=":8" /> Its teeth are straight, laterally flattened, and spindle-shaped in cross-section. However, dentition towards the back of the mouth became more recurved than those in the maxilla. The posterior margin of these [[Crown (tooth)|crowns]] are recurved and convex at its termination. Bowed [[Tooth enamel|enamel wrinkles]] are present on both dorsoventral sides of the crowns. These wrinkles curve towards the marginal serrations, composing a band-shape along the ends.<ref name=":5" /><ref>{{Cite journal |last1=Brusatte |first1=Stephen L. |last2=Benson |first2=Roger B. J. |last3=Carr |first3=Thomas D. |last4=Williamson |first4=Thomas E. |last5=Sereno |first5=Paul C. |date=December 12, 2007 |title=The systematic utility of theropod enamel wrinkles |journal=Journal of Vertebrate Paleontology |volume=27 |issue=4 |pages=1052–1056 |doi=10.1671/0272-4634(2007)27[1052:TSUOTE]2.0.CO;2 |s2cid=85615205 }}</ref><ref name=":11" />

==== Brain and inner ear ====
{{multiple image
| align             = right
| direction         = vertical
| image1            = Carcharodontosaurus braincase.jpg
| image2            = Endocasts of Carcharodontosaurus.jpg
| footer            = Braincase of the neotype (above), with [[endocast]]s of same (A–D) and MB. R. 2056 (E–F) below
| alt1              = Braincase of the C. saharicus neotype
| alt2              = Endocast of the lost Tameryraptor skull.
| total_width       = 170
}}

In 2001, Hans C. E. Larsson published a description of the [[inner ear]] and [[endocranium]] of ''Carcharodontosaurus saharicus''. Starting from the portion of the brain closest to the tip of the animal's snout is the forebrain, which is followed by the midbrain. The [[cephalic flexure|midbrain]] is angled downwards at a 45-degree angle and towards the rear of the animal. This is followed by the [[hindbrain]], which is roughly parallel to the [[forebrain]] and forms a roughly 40-degree [[pontine flexure|angle]] with the midbrain. Overall, the brain of ''C. saharicus'' would have been similar to that of a related dinosaur, ''[[Allosaurus fragilis]].'' Larsson found that the ratio of the [[cerebrum]] to the volume of the brain overall in ''Carcharodontosaurus'' was typical for a non-avian reptile. ''Carcharodontosaurus'' also had a large [[optic nerve]].<ref name="csaharicus-endo">{{cite book | last1 = Larsson | first1 = H.C.E. | date = 2001 | chapter = Endocranial anatomy of ''Carcharodontosaurus saharicus'' (Theropoda: Allosauroidea) and its implications for theropod brain evolution | title = Mesozoic Vertebrate Life | editor-first1 = D.H. | editor-last1 = Tanke | editor-last2 = Carpenter | editor-first2 = K. | editor-last3 = Skrepnick | editor-first3 = M. W. | publisher = Indiana University Press | pages = 219–236|isbn=978-0-253-33907-2|chapter-url=https://archive.org/details/mesozoicvertebra0000unse/page/19/mode/1up|url=https://archive.org/details/mesozoicvertebra0000unse/page/n3/mode/1up|url-access=registration}}</ref>

The three [[semicircular canals]] of the inner ear of ''Carcharodontosaurus saharicus''—when viewed from the side—had a subtriangular outline. This subtriangular inner-ear configuration is present in ''[[Allosaurus]]'', [[lizard]]s, and [[turtle]]s, but not in [[bird]]s. The semi-"circular" canals themselves were very linear, which explains the pointed silhouette. In life, the [[floccular lobe]] of the brain would have projected into the area surrounded by the semicircular canals, just like in other non-avian theropods, birds, and pterosaurs.<ref name="csaharicus-endo" />

=== Postcrania ===
Few postcranial elements are confidently known from ''Carcharodontosaurus,'' though many isolated bones from the Sahara have been referred to the genus without detailed study.<ref name=":6" />{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=169}}{{sfn|Taquet|1976|p=53}}<ref name=":2" /> However, the description of other carcharodontosaurids from North Africa such as ''Tameryraptor'' and ''Sauroniops'' has put into question the referral of carcharodontosaurid remains that lack overlap with the ''C. saharicus'' neotype.<ref name="Tameryraptor" /><ref name=":1" /> Like other carcharodontosaurids, it was robust with small [[forelimb]]s, an elongated [[tail]], and short neck. The most complete specimen was SNSB-BSPG 1922 X 46, but it was destroyed and is now the holotype of ''Tameryraptor''.<ref name="Tameryraptor" /> A single cervical vertebra was referred to the genus by [[Dale A. Russell]] in 1996, the only described postcranial element recovered from the Kem Kem Beds that may belong to ''Carcharodontosaurus''.<ref>{{Cite journal |last1=Evers |first1=Serjoscha W. |last2=Rauhut |first2=Oliver W. M. |last3=Milner |first3=Angela C. |last4=McFeeters |first4=Bradley |last5=Allain |first5=Ronan |date=2015-10-20 |title=A reappraisal of the morphology and systematic position of the theropod dinosaur ''Sigilmassasaurus'' from the "middle" Cretaceous of Morocco |journal=PeerJ |language=en |volume=3 |pages=e1323 |doi=10.7717/peerj.1323 |doi-access=free |issn=2167-8359 |pmc=4614847 |pmid=26500829}}</ref> This cervical vertebra is stout and {{Dinogloss|opisthocoelus}} (concave posterior ends).<ref name="harris1998">{{cite journal |last=Harris |first=Jerald D. |year=1998 |title=A reanalysis of ''Acrocanthosaurus atokensis'', its phylogenetic status, and paleobiological implications, based on a new specimen from Texas |journal=New Mexico Museum of Natural History and Science Bulletin |volume=13 |pages=1–75}}</ref><ref name=":11" /> Its preserved length is {{Convert|148|mm|in}} As in ''Giganotosaurus'', the vertebra is topped by low [[Vertebra|neural spines]] joined with sturdy {{Dinogloss|transverse processes}} which hung over the {{Dinogloss|pleurocoels}} (shallow depressions on the sides of centra), which would contain pneumatic air sacs to lighten the vertebrae. The centrum however lacks the keels observed in other carcharodontosaurids, possibly due to it being an anterior cervical vertebra.<ref>{{cite journal|first=Dale A.|last=Russell|title=Isolated Dinosaur bones from the Middle Cretaceous of the Tafilalt, Morocco|journal=Bulletin du Muséum National d'Histoire Naturelle|year=1996|volume=18|issue=2–3|series=4|pages=569–593|issn=0181-0642|url=https://www.biodiversitylibrary.org/item/249335#page/175/mode/1up|archive-date=May 24, 2022|access-date=March 7, 2025|archive-url=https://web.archive.org/web/20220524104657/https://www.biodiversitylibrary.org/item/249335#page/175/mode/1up|url-status=live}}</ref>

==Classification==
===Systematics===
[[File:Carcharodontosaurus.png|alt=Life restoration of C. saharicus|thumb|right|[[Life restoration]] of ''C. saharicus'']]
''Carcharodontosaurus'' is the type genus of the family Carcharodontosauridae and subfamily [[Carcharodontosauridae|Carcharodontosaurinae]]. This subfamily contains ''Carcharodontosaurus'' itself as well as the other carcharodontosaurines ''Giganotosaurus, Mapusaurus, [[Meraxes]],'' and ''Tyrannotitan''; however, these genera make up an independent tribe: Giganotosaurini. Carcharodontosauridae was a clade created by Stromer for ''Carcharodontosaurus'' and ''Bahariasaurus'', though the name remained unused until the recognition of other members of the group in the late 20th century. He noted the likeness of ''Carcharodontosaurus'' bones to the American theropods ''Allosaurus'' and ''Tyrannosaurus'', leading him to consider the family part of Theropoda.{{sfn|Stromer|1934|pp=60–61}}<ref name=":8" />

Paul Sereno's description of ''Carcharodontosaurus'' fossils in 1996 led to the realization of a transcontinental clade of carcharodontosaurids. As more carcharodontosaurids were discovered, their interrelationships became even clearer. The group was defined as all allosauroids closer to ''Carcharodontosaurus'' than ''Allosaurus'' or ''[[Sinraptor]]'' by the paleontologist [[Thomas R. Holtz]] and colleagues in 2004.<ref name="sciencedirect.com">{{Cite journal |last1=Novas |first1=Fernando E. |last2=Agnolín |first2=Federico L. |last3=Ezcurra |first3=Martín D. |last4=Porfiri |first4=Juan |last5=Canale |first5=Juan I. |date=October 1, 2013 |title=Evolution of the carnivorous dinosaurs during the Cretaceous: The evidence from Patagonia |journal=Cretaceous Research |volume=45 |pages=174–215 |doi=10.1016/j.cretres.2013.04.001 |bibcode=2013CrRes..45..174N |hdl=11336/102037|s2cid=129504278 |hdl-access=free }}</ref> ''Carcharodontosaurus'' is more poorly known than most other carcharodontosaurids, with ''Meraxes'' and ''Giganotosaurus'' represented by nearly complete skeletons.<ref name="Canale2022">{{Cite journal |last1=Canale |first1=Juan I. |last2=Apesteguía |first2=Sebastián |last3=Gallina |first3=Pablo A. |last4=Mitchell |first4=Jonathan |last5=Smith |first5=Nathan D. |last6=Cullen |first6=Thomas M. |last7=Shinya |first7=Akiko |last8=Haluza |first8=Alejandro |last9=Gianechini |first9=Federico A. |last10=Makovicky |first10=Peter J. |date=July 7, 2022 |title=New giant carnivorous dinosaur reveals convergent evolutionary trends in theropod arm reduction |journal=Current Biology |volume=32 |issue=14 |pages=3195–3202.e5 |doi=10.1016/j.cub.2022.05.057 |pmid=35803271 |s2cid=250343124 |doi-access=free |bibcode=2022CBio...32E3195C }}</ref><ref name=":15" /> Carcharodontosaurians have been recognized from the [[Late Jurassic]] to the Mid-Cretaceous of every continent except Antarctica.<ref name=":17">{{Cite journal |last1=Coria |first1=Rodolfo A. |last2=Currie |first2=Philip J. |last3=Ortega |first3=Francisco |last4=Baiano |first4=Mattia A. |date=July 1, 2020 |title=An Early Cretaceous, medium-sized carcharodontosaurid theropod (Dinosauria, Saurischia) from the Mulichinco Formation (upper Valanginian), Neuquén Province, Patagonia, Argentina |journal=Cretaceous Research |volume=111 |pages=104319 |doi=10.1016/j.cretres.2019.104319 |bibcode=2020CrRes.11104319C |hdl=11336/122794 |s2cid=214475057 |hdl-access=free }}</ref><ref>{{Cite journal |last1=Brusatte |first1=Stephen L. |last2=Benson |first2=Roger B.J. |last3=Xu |first3=Xing |date=2012 |title=A Reassessment of ''Kelmayisaurus petrolicus'', a Large Theropod Dinosaur from the Early Cretaceous of China |journal=Acta Palaeontologica Polonica |volume=57 |issue=1 |pages=65–72 |doi=10.4202/app.2010.0125 |s2cid=53387460 |doi-access=free |hdl=20.500.11820/95de36fb-46b2-4acc-bd2e-1d5a496fc78c |hdl-access=free }}</ref><ref name=":5" /><ref>{{Cite journal |last1=Kotevski |first1=Jake |last2=Duncan |first2=Ruairidh J. |last3=Ziegler |first3=Tim |last4=Bevitt |first4=Joseph J. |last5=Vickers-Rich |first5=Patricia |last6=Rich |first6=Thomas H. |last7=Evans |first7=Alistair R. |last8=Poropat |first8=Stephen F. |title=Evolutionary and paleobiogeographic implications of new carcharodontosaurian, megaraptorid, and unenlagiine theropod remains from the upper Lower Cretaceous of Victoria, southeast Australia |url=https://www.tandfonline.com/doi/full/10.1080/02724634.2024.2441903?s=04&fbclid=IwY2xjawIjLKdleHRuA2FlbQIxMQABHUyzuupFFj1lvGMHco5BrUwax1YTsiLx9T244449qie-QMvdFC7YqHssZw_aem_8X4FfXyB4WaNw3rjXwBrfg#abstract |journal=Journal of Vertebrate Paleontology |date=2025 |volume=0 |pages=e2441903 |doi=10.1080/02724634.2024.2441903 |issn=0272-4634|url-access=subscription }}</ref>

In their [[phylogenetic analyses]], Kellermann, Cuesta & Rauhut (2025) recovered ''C. iguidensis'' as a non-carcharodontosaurine member of the [[Carcharodontosauridae]] outside the genus ''Carcharodontosaurus'', suggesting that this species belongs to a different genus.<ref name=Tameryraptor/> Similar results were recovered by Cau & Paterna (2025) in their analysis of large Cretaceous theropods from Africa, who also argued for the removal of ''C. iguidensis'' from the genus.<ref name="Cau&Paterna25">{{Cite journal |last1=Cau |first1=Andrea |author1-link=Andrea Cau |last2=Paterna |first2=Alessandro |date=May 2025 |title=Beyond the Stromer's Riddle: the impact of lumping and splitting hypotheses on the systematics of the giant predatory dinosaurs from northern Africa |url=https://www.italianjournalofgeosciences.it/297/article-1220/beyond-the-stromer-s-riddle-the-impact-of-lumping-and-splitting-hypotheses-on-the-systematics-of-the-giant-predatory-dinosaurs-from-northern-africa.html |journal=Italian Journal of Geosciences |volume=144 |issue=2 |pages=1–24 |doi=10.3301/IJG.2025.10 |url-access=subscription |archive-date=May 14, 2025 |access-date=May 10, 2025 |archive-url=https://web.archive.org/web/20250514194900/https://www.italianjournalofgeosciences.it/297/article-1220/beyond-the-stromer-s-riddle-the-impact-of-lumping-and-splitting-hypotheses-on-the-systematics-of-the-giant-predatory-dinosaurs-from-northern-africa.html |url-status=live }}</ref>

The analyses of Kellermann, Cuesta & Rauhut (2025) found support for a [[sister taxon]] relationship of carcharodontosaurids and [[metriacanthosaurid]]s, which the authors named as a new clade, [[Carcharodontosauriformes]]. The results of their analysis using merged OTUs (operational taxonomic units) are displayed in the [[cladogram]] below:<ref name=Tameryraptor/>

{{clade
 |{{clade
  |1=[[Metriacanthosauridae]] <div style="{{MirrorH}}">[[File:Alpkarakush kyrgyzicus.png|80px]]</div>
  |label2=[[Carcharodontosauridae]]
  |2={{clade
  |1={{clade
   |1=''[[Lusovenator]]''
   |2=''[[Lajasvenator]]'' }}
   |3={{clade
  |1=''[[Acrocanthosaurus]]'' <div style="{{MirrorH}}">[[File:Acrocanthosaurus restoration.jpg|80px]]</div>
  |2={{clade
   |1=''[[Tameryraptor]]'' <div style="{{MirrorH}}">[[File:Tameryraptor markgrafi.png|75px]]</div>
   |2={{clade
    |1='''''Carcharodontosaurus iguidensis'''''
    |label2=[[Carcharodontosaurinae]]
    |2={{clade
    |1={{clade
     |1=''[[Taurovenator]]''
     |2='''''Carcharodontosaurus saharicus''''' <div style="{{MirrorH}}">[[File:Carcharodontosaurus.png|70px]]</div> }}
     |label3=[[Giganotosaurini]]
     |3={{clade
    |1=''[[Meraxes]]'' <div style="{{MirrorH}}">[[File:Life reconstruction of Meraxes gigas.png|85px]]</div>
    |2={{clade
     |1=''[[Tyrannotitan]]''
     |2={{clade
      |1=''[[Mapusaurus]]'' <div style="{{MirrorH}}">[[File:Mapusaurus Roseae restoration.png|80px]]</div>
      |2=''[[Giganotosaurus]]'' <div style="{{MirrorH}}">[[File:Giganotos Db.jpg|70px]]</div>
}} }} }} }} }} }} }} }} }}|label1=[[Carcharodontosauriformes]]}}

=== Evolution ===
[[Rodolfo Coria]] and [[Leonardo Salgado]] suggested that the [[convergent evolution]] of gigantism in theropods could have been linked to common conditions in their environments or [[ecosystems]].<ref name=":15">{{Cite journal |last1=Coria |first1=Rodolfo A. |last2=Salgado |first2=Leonardo |date=1995 |title=A new giant carnivorous dinosaur from the Cretaceous of Patagonia |journal=Nature |volume=377 |issue=6546 |pages=224–226 |doi=10.1038/377224a0 |bibcode=1995Natur.377..224C |s2cid=30701725 }}</ref> Sereno and colleagues found that the presence of carcharodontosaurids in Africa (''Carcharodontosaurus''), North America (''Acrocanthosaurus''), and South America (''Giganotosaurus''), showed the group had a transcontinental distribution by the [[Early Cretaceous]] [[Period (geology)|period]]. [[Biological dispersal|Dispersal routes]] between the northern and southern continents appear to have been severed by ocean barriers in the Late Cretaceous, which led to more distinct, provincial faunas, by preventing exchange.<ref>{{Cite journal |last=Currie |first=Philip J. |date=May 17, 1996 |title=Out of Africa: Meat-Eating Dinosaurs That Challenge ''Tyrannosaurus rex'' |journal=Science |volume=272 |issue=5264 |pages=971–972 |doi=10.1126/science.272.5264.971 |bibcode=1996Sci...272..971C |s2cid=85110425 }}</ref><ref name=":5" /> Previously, it was thought that the Cretaceous world was [[biogeographically]] separated, with the northern continents being dominated by tyrannosaurids, South America by [[Abelisauridae|abelisaurids]], and Africa by carcharodontosaurids.<ref name="Coria1996">{{cite journal |last1=Coria |first1=Rodolfo A. |last2=Salgado |first2=Leonardo |date=June 1996 |title=Dinosaurios carnívoros de Sudamérica |url=http://www.investigacionyciencia.es/revistas/investigacion-y-ciencia/numero/237/dinosaurios-carnvoros-de-sudamrica-6530 |journal=Investigación y Ciencia |language=es |issue=237 |pages=39–40}}</ref> The subfamily Carcharodontosaurinae, in which ''Carcharodontosaurus'' belongs, appears to have been restricted to the southern continent of [[Gondwana]] (formed by South America and Africa), where they were probably the [[apex predator]]s.<ref name="sciencedirect.com"/> The South American tribe Giganotosaurini may have been separated from their African relatives through [[vicariance]], when Gondwana broke up during the [[Aptian]]–[[Albian]] ages of the Early Cretaceous.<ref name="Tyrannotitan2014">{{cite journal |last1=Canale |first1=J. I. |last2=Novas |first2=F. E. |last3=Pol |first3=D. |date=2014 |title=Osteology and phylogenetic relationships of ''Tyrannotitan chubutensis'' Novas, de Valais, Vickers-Rich and Rich, 2005 (Theropoda: Carcharodontosauridae) from the Lower Cretaceous of Patagonia, Argentina |journal=Historical Biology |volume=27 |issue=1 |pages=1–32 |doi=10.1080/08912963.2013.861830 |s2cid=84583928 |hdl-access=free |hdl=11336/17607 }}</ref>

==Paleobiology==
=== Lifting capabilities ===
A biomechanical analysis of ''Carcharodontosaurus''<nowiki/>' lifting capabilities was conducted by paleontologist [[Donald Henderson (paleontologist)|Donald Henderson]] and paleoartist [[Robert Nicholls (artist)|Robert Nicholls]] in 2015. The authors used 3D models of the animal as well as a subadult [[Sauropoda|sauropod]] ''[[Limaysaurus]]'', which although not found alongside ''Carcharodontosaurus'', is similar to the [[Rebbachisauridae|rebbachisaurids]] of the Kem Kem Beds. The models included the size of the [[lung]]s and other pneumatic structures of the two, fostering an accurate weight simulation of the scenario. Henderson & Nicholls' study found that an adult ''C. saharicus'' could hold a maximum of {{cvt|424|kg}}, half the weight of an adult ''Limaysaurus''. However, two ''C. saharicus'' adults could together lift as much as {{Convert|850|kg|lb}}.<ref name="Henderson&Nicholls2015" />

=== Feeding and diet ===
[[File:Carcharodontosaurus teeth.jpg|thumb|292x292px|Teeth referred to ''Carcharodontosaurus'']]
The dentition of allosauroids is distinct, with carcharodontosaurid teeth bearing distinctly thin and blade-like teeth. However, these teeth are thin and likely could not sustain impact against hard surfaces like bone without potentially bending and snapping. This danger is exacerbated by the straight edges, slightly recurved tips, and [[sinusoidal]] shapes observed in their dentition. Despite these traits, the teeth are still much more robust than those of smaller theropods and due to their overall size could take more pressure. ''Carcharodontosaurus'' also had a high tooth replacement rate meaning that damaged teeth could be replaced easily in contrast to extant bone-crushing mammals who spend much of their energy maintaining their teeth.<ref>{{Cite journal |last=Van Valkenburgh |first=Blaire |date=1988 |title=Incidence of Tooth Breakage Among Large, Predatory Mammals |journal=The American Naturalist |volume=131 |issue=2 |pages=291–302 |doi=10.1086/284790 |s2cid=222330098 |jstor=2461849|bibcode=1988ANat..131..291V }}</ref><ref>{{Cite journal |last=Van Valkenburgh |first=Blaire |year=2008 |title=Costs of carnivory: tooth fracture in Pleistocene and Recent carnivorans |journal=Biological Journal of the Linnean Society |volume=96 |issue=1 |pages=68–81 |doi=10.1111/j.1095-8312.2008.01108.x |s2cid=85623961 |doi-access=free }}</ref> Evidence of bone-crunching bites is observed in ''Allosaurus'', which would engage in ritual face-biting with other individuals and bite into the pelves of ''Stegosaurus'' as shown by bite marks.<ref>{{Cite journal |last1=Hone |first1=David W. E. |last2=Rauhut |first2=Oliver W. M. |date=2010 |title=Feeding behaviour and bone utilization by theropod dinosaurs |journal=Lethaia |volume=43 |issue=2 |pages=232–244 |doi=10.1111/j.1502-3931.2009.00187.x |bibcode=2010Letha..43..232H |s2cid=86037076}}</ref><ref>{{Cite journal |last1=Tanke |first1=Darren H.|last2=Currie |first2=Phillip J. |date=1998 |title=Head-biting behavior in theropod dinosaurs: Paleopathological evidence |journal=Gaia|issue=15|pages=167–184|doi=10.7939/R34T6FJ1P |s2cid=90552600 |doi-access=free}}</ref><ref>{{Cite journal |last1=Drumheller |first1=Stephanie K. |last2=McHugh |first2=Julia B. |last3=Kane |first3=Miriam |last4=Riedel |first4=Anja |last5=D’Amore |first5=Domenic C. |date=May 27, 2020 |title=High frequencies of theropod bite marks provide evidence for feeding, scavenging, and possible cannibalism in a stressed Late Jurassic ecosystem |journal=PLOS ONE |volume=15 |issue=5 |pages=e0233115 |doi=10.1371/journal.pone.0233115 |pmid=32459808 |pmc=7252595 |bibcode=2020PLoSO..1533115D |doi-access=free }}</ref>

Bite forces of ''Carcharodontosaurus'' as well as other giant theropods including ''Acrocanthosaurus'' and ''Tyrannosaurus'' have been analyzed. Studies reported that carcharodontosaurids had much lower bite forces than ''Tyrannosaurus'' despite being in the same size class. The anterior bite force of ''C. saharicus'' was estimated in a 2022 paper to be 11,312 newtons while the posterior bite force was 25,449 newtons. This is much lower than that of ''Tyrannosaurus,'' implying that it did not eat bones.<ref>{{Cite journal |last=Sakamoto |first=Manabu |date=July 12, 2022 |title=Estimating bite force in extinct dinosaurs using phylogenetically predicted physiological cross-sectional areas of jaw adductor muscles |journal=PeerJ |volume=10 |pages=e13731 |doi=10.7717/peerj.13731 |pmc=9285543 |pmid=35846881 |doi-access=free }}</ref><ref>{{Cite journal |last1=Gignac |first1=Paul M. |last2=Erickson |first2=Gregory M. |date=May 17, 2017 |title=The Biomechanics Behind Extreme Osteophagy in ''Tyrannosaurus rex'' |journal=Scientific Reports |volume=7 |issue=1 |pages=2012 |doi=10.1038/s41598-017-02161-w |pmc=5435714 |pmid=28515439|bibcode=2017NatSR...7.2012G |doi-access=free }}</ref> Finite element accounts of the skulls of theropods have also been taken, which further supported the idea that ''Carcharodontosaurus'' ate softer food than tyrannosaurids. Great amounts of stress were recovered in the posterior part of the cranium near the quadrate in ''Carcharodontosaurus, Spinosaurus,'' and ''Acrocanthosaurus''. The skulls of these theropods had higher relative stress quantities in opposition to that of smaller genera. This indicates that the crania of giant taxa (ex. ''Carcharodontosaurus'') were unstable due to having large pneumatic structures to save weight instead of creating a firm build. However, ''Spinosaurus'' and ''[[Suchomimus]]'' experienced even greater values of stress meaning that they could only consume light, small prey instead of larger items, which the stronger skull of ''Carcharodontosaurus'' could bite while sustaining the stress.<ref>{{cite book |last1=Rayfield |first1=Emily J. |title=STUDIES ON FOSSIL TETRAPODS |date=2011 |publisher=Palaeontological Association |pages=241–253 |chapter=Structural performance of tetanuran theropod skulls, with emphasis on the Megalosauridae, Spinosauridae and Carcharodontosauridae |hdl=1983/aaaea1c8-8c3a-4f99-abd6-982b47664aac |isbn=978-1-4443-6189-6 }}</ref>

Isotopic analyses of the teeth of ''C. saharicus'' have found δ18O values that are higher than that of the contemporary ''Spinosaurus'', suggesting the latter pursued semi-aquatic habits whereas ''Carcharodontosaurus'' was more terrestrial.<ref name=":13">{{Cite journal |last1=Goedert |first1=J. |last2=Amiot |first2=R. |last3=Boudad |first3=L. |last4=Buffetaut |first4=E. |author-link4=Éric Buffetaut |last5=Fourel |first5=F. |last6=Godefroit |first6=P. |last7=Kusuhashi |first7=N. |last8=Suteethorn |first8=V. |last9=Tong |first9=H. |last10=Watabe |first10=M. |last11=Lecuyer |first11=C. |date=2016 |title=Preliminary investigation of seasonal patterns recorded in the oxygen isotope compositions of theropod dinosaur tooth enamel. |journal=PALAIOS |volume=31 |issue=1 |pages=10–19|doi=10.2110/palo.2015.018 |bibcode=2016Palai..31...10G |s2cid=130878403 }}</ref> This is further supported by the taphonomy of ''C. saharicus'' teeth, which are more often found in land terrains than aquatic ones.<ref name=":12" /> ''Carcharodontosaurus'' was also a [[Homeothermy|homeotherm]] with an [[endotherm]]-like [[Thermoregulation|thermophysiology]] as inferred by these isotopes meaning that most of its oxygen was accumulated by drinking water rather than being in it.<ref>{{Cite journal |last1=Amiot |first1=Romain |last2=Wang |first2=Xu |last3=Lécuyer |first3=Christophe |last4=Buffetaut |first4=Eric |last5=Boudad |first5=Larbi |last6=Cavin |first6=Lionel |last7=Ding |first7=Zhongli |last8=Fluteau |first8=Frédéric |last9=Kellner |first9=Alexander W.A. |last10=Tong |first10=Haiyan |last11=Zhang |first11=Fusong |date=2010 |title=Oxygen and carbon isotope compositions of middle Cretaceous vertebrates from North Africa and Brazil: Ecological and environmental significance |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=297 |issue=2 |pages=439–451 |doi=10.1016/j.palaeo.2010.08.027 |bibcode=2010PPP...297..439A |s2cid=131607253 }}</ref><ref>{{Cite journal |last1=Amiot |first1=Romain |last2=Lécuyer |first2=Christophe |last3=Buffetaut |first3=Eric |last4=Escarguel |first4=Gilles |last5=Fluteau |first5=Frédéric |last6=Martineau |first6=François |date=June 15, 2006 |title=Oxygen isotopes from biogenic apatites suggest widespread endothermy in Cretaceous dinosaurs |journal=Earth and Planetary Science Letters |volume=246 |issue=1 |pages=41–54 |doi=10.1016/j.epsl.2006.04.018 |bibcode=2006E&PSL.246...41A |s2cid=55100956 |jstor=41125672 }}</ref>

=== Crest function ===
Theropods such as ''Carcharodontosaurus, Allosaurus,'' and ''Acrocanthosaurus'' have enlarged lacrimal crests, whose purpose is unknown. Paleontologist Daniel Chure hypothesized that these crests were used for "head-butting" between individuals, but how durable they are has not been studied.<ref>{{Cite journal |last=Chure |first=Daniel |date=2000 |title=On the orbit of theropod dinosaurs. |url=https://www.researchgate.net/publication/228550944 |journal=Gaia |volume=15 |pages=233–240}}</ref>

=== Vision ===
{{multiple image
| align             = right
| direction         = horizontal
| total_width       = 280
| image1            = Carcharodontosaurus saharicus theropod dinosaur (Kem Kem beds, Upper Cretaceous; Gara es Sbaa, Kem Kem region, southeastern Morocco) 3 (15375691822).jpg
| alt1              = Skull of C. saharicus
| image2            = Carcharodontosaurus saharicus theropod dinosaur (Kem Kem beds, Upper Cretaceous; Gara es Sbaa, Kem Kem region, southeastern Morocco) 2 (15352983706).jpg
| alt2              = 
| footer            = Skull of ''C. saharicus'' showing its elongated, thin rostrum and limited degree of binocular vision
}}

A 2006 study by biologist [[Kent Stevens]] analyzed the [[binocular vision]] capabilities of the allosauroids ''Carcharodontosaurus'' and ''Allosaurus'' as well as several [[Coelurosauria|coelurosaurs]] including ''Tyrannosaurus'' and ''[[Stenonychosaurus]]''. By applying [[Visual field test|modified perimetry]] to models of these dinosaurs' heads, Stevens deduced that the binocular vision of ''Carcharodontosaurus'' was limited, a side effect of its large, elongated rostrum. Its greatest degree of binocular vision was at higher elevations, suggesting that ''Carcharodontosaurus'' may have habitually held its head at a downward 40° angle with its eyes facing up accordingly to achieve maximum binocular vision. The range of vision seen in these allosauroids is comparable to that of crocodiles, suggesting that they were [[ambush predator]]s. They likely sensed prey via [[Parallax|motion parallax]] between prey and background, with a narrow binocular field of vision helping predators judge prey distances and time attacks.<ref>{{Cite journal |last=Stevens |first=Kent A. |date=June 12, 2006 |title=Binocular vision in theropod dinosaurs |journal=Journal of Vertebrate Paleontology |volume=26 |issue=2 |pages=321–330 |doi=10.1671/0272-4634(2006)26[321:BVITD]2.0.CO;2 |s2cid=85694979 |jstor=4524572 }}</ref>

===Pathology===
{{Main|Theropod paleopathology}}
The neotype skull of ''C. saharicus'' is one of many allosauroid individuals to preserve [[Pathology|pathologies]], with signs of biting, infection, and breaks observed in ''Allosaurus'' and ''Acrocanthosaurus'' among others.<ref>{{Cite journal |last1=Chinsamy |first1=Anusuya |last2=Tumarkin-Deratzian |first2=Allison |date=2009 |title=Pathologic Bone Tissues in a Turkey Vulture and a Nonavian Dinosaur: Implications for Interpreting Endosteal Bone and Radial Fibrolamellar Bone in Fossil Dinosaurs |journal=The Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology |volume=292 |issue=9 |pages=1478–1484 |doi=10.1002/ar.20991 |pmid=19711479 |s2cid=41596233 |doi-access=free }}</ref><ref name="Molnar2001">{{cite book |last1=Molnar |first1=R. E.|editor1-last=Carpenter |editor1-first=Kenneth |editor2-last=Skrepnick |editor2-first=Michael William |editor3-last=Tanke |editor3-first=Darren H. |title=Mesozoic Vertebrate Life |date=2001 |publisher=Indiana Univ. Press |isbn=978-0-253-33907-2 |pages=337–363 |chapter=Theropod Paleopathology: A Literature Survey |oclc=248649755 }}</ref> This skull bears a circular puncture wound in the nasal and "an abnormal projection of bone on the antorbital rim".<ref name="Molnar2001"/> A later study theorized that this was the result of craniofacial bites.<ref>{{cite book |last1=Rothschild |first1=Bruce |title=The Carnivorous Dinosaurs |last2=Tanke |first2=Darren |publisher=Indiana University Press |year=2005 |isbn=978-0-253-34539-4 |edition=1st |location=Indianapolis |page=351 |chapter=Theropod paleopathology: state-of-the-art review }}</ref>

== Paleoenvironment ==
Fossils of ''Carcharodontosaurus'' are known from several Cretaceous-age sites across North Africa, similar to the ranges of ''Spinosaurus'' and ''[[Deltadromeus]]''.<ref name=":0" /><ref name=":5" /> North Africa during this period bordered the [[Tethys Ocean|Tethys Sea]], which transformed the region into a [[mangrove]]-dominated coastal environment filled with vast [[Mudflat|tidal flats]] and [[waterway]]s.<ref>{{Cite journal |last1=Hamed |first1=Younes |last2=Al-Gamal |first2=Samir Anwar |last3=Ali |first3=Wassim |last4=Nahid |first4=Abederazzak |last5=Dhia |first5=Hamed Ben |date=March 1, 2014 |title=Palaeoenvironments of the Continental Intercalaire fossil from the Late Cretaceous (Barremian-Albian) in North Africa: a case study of southern Tunisia |journal=Arabian Journal of Geosciences |volume=7 |issue=3 |pages=1165–1177 |doi=10.1007/s12517-012-0804-2 |bibcode=2014ArJG....7.1165H |s2cid=128755145 }}</ref>{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=185}} Isotopes from ''Carcharodontosaurus'' and ''Spinosaurus'' fossils suggest that the Kem Kem Beds witnessed a temporary [[Wet season|monsoon season]] rather than constant rainfall, similar to modern conditions present in [[Subtropics|sub-tropical]] and [[Tropics|tropical]] environments in [[Southeast Asia]] and [[Sub-Saharan Africa]].<ref name=":13" /><ref name="RMetal102">{{cite journal |last1=Amiot |first1=Romain |last2=Buffetaut |first2=Eric |last3=Lécuyer |first3=Christophe |last4=Wang |first4=Xu |last5=Boudad |first5=Larbi |last6=Ding |first6=Zhongli |last7=Fourel |first7=François |last8=Hutt |first8=Steven |last9=Martineau |first9=François |last10=Medeiros |first10=Manuel Alfredo |last11=Mo |first11=Jinyou |last12=Simon |first12=Laurent |last13=Suteethorn |first13=Varavudh |last14=Sweetman |first14=Steven |last15=Tong |first15=Haiyan |last16=Zhang |first16=Fusong |last17=Zhou |first17=Zhonghe |title=Oxygen isotope evidence for semi-aquatic habits among spinosaurid theropods |journal=Geology |date=February 2010 |volume=38 |issue=2 |pages=139–142 |doi=10.1130/G30402.1 |bibcode=2010Geo....38..139A }}</ref> These riverine deposits bore large fishes, including the [[Sclerorhynchoidei|sawskate]] ''[[Onchopristis]]'', [[coelacanth]] ''[[Mawsonia (fish)|Mawsonia]]'', and [[bichir]] ''[[Bawitius]]''.{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=184}} This led to an abundance of piscivorous [[crocodyliformes]] evolving in response, such as the giant [[Stomatosuchidae|stomatosuchid]] ''[[Stomatosuchus]]'' in Egypt and the genera ''[[Elosuchus]], [[Laganosuchus]],'' and ''[[Aegisuchus]]'' from Morocco.<ref>{{Cite journal |last1=Holliday |first1=Casey M. |last2=Gardner |first2=Nicholas M. |date=January 31, 2012 |title=A New Eusuchian Crocodyliform with Novel Cranial Integument and Its Significance for the Origin and Evolution of Crocodylia |journal=PLOS ONE |volume=7 |issue=1 |pages=e30471 |doi=10.1371/journal.pone.0030471 |pmc=3269432 |pmid=22303441 |bibcode=2012PLoSO...730471H |doi-access=free }}</ref>{{sfn|Ibrahim|Sereno|Varricchio|Martill|2020|p=180, 189}} Morocco also bore an abundance of pterosaurs like ''[[Siroccopteryx]]'' and ''[[Nicorhynchus]]''.<ref>{{Cite journal |last1=Ibrahim |first1=Nizar |last2=Unwin |first2=David M. |last3=Martill |first3=David M. |last4=Baidder |first4=Lahssen |last5=Zouhri |first5=Samir |date=May 26, 2010 |title=A New Pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco |journal=PLOS ONE |volume=5 |issue=5 |pages=e10875 |doi=10.1371/journal.pone.0010875 |pmc=2877115 |pmid=20520782 |bibcode=2010PLoSO...510875I |doi-access=free }}</ref><ref name="APPanhanguerids">{{cite journal |author1=Borja Holgado |author2=Rodrigo V. Pêgas |year=2020 |title=A taxonomic and phylogenetic review of the anhanguerid pterosaur group Coloborhynchinae and the new clade Tropeognathinae |journal=Acta Palaeontologica Polonica |volume=65 |issue=4 |pages=743–761 |doi=10.4202/app.00751.2020 |s2cid=222075296|doi-access=free }}</ref>

The composition of the dinosaur fauna of these sites is an anomaly, as there are fewer herbivorous dinosaur species relative to carnivorous dinosaurs than usual. This indicates that there was niche partitioning between the different theropod clades, with spinosaurids consuming fish while other groups hunted herbivorous dinosaurs.<ref>{{Cite journal |last1=Ibrahim |first1=N |last2=Dal Sasso |first2=C |last3=Maganuco |first3=S |last4=Fabbri |first4=M |last5=Martill |first5=D |last6=Gorscak |first6=E |last7=Lamanna |first7=M |date=2016 |title=Evidence of a derived titanosaurian (Dinosauria, Sauropoda) in the 'Kem Kem beds' of Morocco, with comments on sauropod paleoecology in the Cretaceous of Africa |url=https://econtent.unm.edu/digital/collection/bulletins/id/5964 |journal=Cretaceous Period: Biotic Diversity and Biogeography. New Mexico Museum of Natural History and Science Bulletin |volume=71 |pages=149–159 }}</ref> Isotopic evidence supports this, which found greater quantities of sizable, terrestrial animals in the diets of carcharodontosaurids and ceratosaurs from both the Kem Kem Beds and Elrhaz Formation.<ref>{{Cite journal |last1=Hassler |first1=A. |last2=Martin |first2=J. E. |last3=Amiot |first3=R. |last4=Tacail |first4=T. |last5=Godet |first5=F. Arnaud |last6=Allain |first6=R. |last7=Balter |first7=V. |date=April 11, 2018 |title=Calcium isotopes offer clues on resource partitioning among Cretaceous predatory dinosaurs |journal=Proceedings of the Royal Society B: Biological Sciences |volume=285 |issue=1876 |pages=20180197 |doi=10.1098/rspb.2018.0197 |pmc=5904318 |pmid=29643213 }}</ref><ref name=":2" /> It also coexisted with the sauropod ''[[Rebbachisaurus]]'' which is found in the Kem Kem Beds.<ref>{{Cite journal |last1=Wilson |first1=Jeffrey A. |last2=Allain |first2=Ronan |date=July 4, 2015 |title=Osteology of ''Rebbachisaurus garasbae'' Lavocat, 1954, a diplodocoid (Dinosauria, Sauropoda) from the early Late Cretaceous–aged Kem Kem beds of southeastern Morocco |journal=Journal of Vertebrate Paleontology |volume=35 |issue=4 |pages=e1000701 |doi=10.1080/02724634.2014.1000701 |bibcode=2015JVPal..35E0701W |s2cid=129846042 }}</ref> Carcharodontosaurids are represented by ''C. saharicus'' and ''Sauroniops'' in the Kem Kem Beds, ''Tameryraptor'' in the Bahariya Formation, ''[[Eocarcharia]]'' and potentially ''Carcharodontosaurus'' in the Elrhaz Formation, and ''C. iguidensis'' in the Echkar Formation.<ref name=":6" />

==References==
{{reflist}}

==Bibliography==
{{refbegin|40em}}
* {{cite journal|last=Stromer|first=Ernst|year=1934|title=Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltier-Reste der Baharije-Stufe (unterstes Cenoman). 13. Dinosauria|journal=Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematisch-naturwissenschaftliche Abteilung|series=Neue Folge|language=de|volume=22|pages=1–79|url=https://www.zobodat.at/pdf/Abhandlungen-Akademie-Bayern_NF_22_0001-0079.pdf}}
* {{cite book |last1=Taquet |first1=Philippe |title=Géologie et paléontologie du gisement de Gadoufaoua (aptien du Niger) |date=1976 |publisher=Éditions du Centre national de la recherche scientifique |isbn=978-2-222-02018-9 |language=fr }}
* {{Cite book|first1=William|last1=Nothdurft|first2=Josh|last2=Smith|title=The Lost Dinosaurs of Egypt|year=2002|publisher=[[Random House|Random House Publishing Group]]|isbn=978-1-58836-117-2|place=New York|url=https://books.google.com/books?id=Axu-z-FXyboC&pg=PT28}}
* {{Cite journal|last1=Ibrahim|first1=Nizar|last2=Sereno|first2=Paul C.|last3=Varricchio|first3=David J.|last4=Martill|first4=David M.|last5=Dutheil|first5=Didier B.|last6=Unwin|first6=David M.|last7=Baidder|first7=Lahssen|last8=Larsson|first8=Hans C. E.|last9=Zouhri|first9=Samir|last10=Kaoukaya|first10=Abdelhadi|year=2020|title=Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco|journal=[[ZooKeys]]|issue=928|pages=1–216|doi=10.3897/zookeys.928.47517 |pmc=7188693|pmid=32362741|bibcode=2020ZooK..928....1I|doi-access=free}}
{{refend}}

{{Theropoda|A.}}
{{Taxonbar|from1=Q14431|from2=Q2313178|from3=Q12899173}}

[[Category:Carcharodontosauridae]]
[[Category:Dinosaur genera]]
[[Category:Cenomanian dinosaurs]]
[[Category:Fossil taxa described in 1931]]
[[Category:Taxa named by Ernst Stromer]]
[[Category:Dinosaurs of Morocco]]
[[Category:Taxa with lost type specimens]]