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'{{Italic title}} {{Automatic taxobox | name = ''Mapusaurus'' | fossil_range = [[Late Cretaceous]], {{fossil range|95|earliest=97|latest=94}} | image = Mapusaurus.jpg | image_width = 250px | image_caption = Reconstructed skeletons of an adult and juvenile | authority = [[Rodolfo Coria|Coria]] & [[Phil Currie|Currie]], [[2006 in paleontology|2006]] | subdivision_ranks = [[Species]] | subdivision = *[[extinction|†]]'''''M. roseae''''' <small>Coria & Currie, 2006 ([[type species|type]])</small> }} '''''Mapusaurus''''' ("earth lizard") was a giant [[carnosauria]]n [[dinosaur]] from the early [[Late Cretaceous]] ([[Cenomanian]] stage) of what is now [[Argentina]]. ==Description== [[File:Mapusaurus scale.png|thumb|left|Size compared to a human, based on the largest fragmentary specimen]] It was similar in size to its close relative ''[[Giganotosaurus]]'', with the largest known individuals estimated as over {{convert|10.2|m|ft}} in length and weighing approximately {{convert|3|MT|ST}}.<ref name="coria&currie2006">{{cite journal | last1 = Coria | first1 = R. A. | last2 = Currie | first2 = P. J. | year = 2006 | title = A new carcharodontosaurid (Dinosauria, Theropoda) from the Upper Cretaceous of Argentina | url = http://www.mnhn.fr/museum/front/medias/publication/7653_g06n1a4.pdf | journal = Geodiversitas | volume = 28 | issue = 1| pages = 71–118 |issn=1280-9659 }}</ref> The longest individual for which Coria and Currie (2006) provided an estimate is the animal to which femur MCF-PVPH-208.203 belonged; this individual is estimated as {{convert|10.2|m|ft}} long. Coria and Currie note the presence of isolated bones from at least one longer individual, but do not provide a figure, instead finding the larger bones comparable in size to those from a ''[[Giganotosaurus]]'' estimated at {{convert|12.2|m|ft}} in length. Maximum length is thus unknown but greater than {{convert|12.2|m|ft}}. The weight estimate is from another femur (MCF-PVPH-208.234). It was furthermore concluded that the largest remain, a pubic shaft, was 110% the size of the ''Giganotosaurus'' holotype. Holtz estimated it at {{convert|12.6|m|ft}}.<ref name="Holtz2008">Holtz, Thomas R. Jr. (2012) ''Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,'' [http://www.geol.umd.edu/~tholtz/dinoappendix/HoltzappendixWinter2011.pdf Winter 2011 Appendix.]</ref> In an analysis on the cranial anatomy of carcharodontosaurids, Drew Eddy and Julia Clarke (2011) estimated the size of ''Mapusaurus'' at {{convert|12.6|m|ft}}.<ref>{{cite journal|title=Eddy DR, Clarke JA (2011) New Information on the Cranial Anatomy of Acrocanthosaurus atokensis and Its Implications for the Phylogeny of Allosauroidea (Dinosauria: Theropoda). PLoS ONE 6(3): e17932. doi:10.1371/journal.pone.0017932}}</ref> this estimate was repeated in a calibrated phylogenetic table in a 2014 analysis by Canale ''et al''.<ref>{{cite journal|title=Canale JI, Novas FE, Salgado L, Coria RA. 2014. Cranial ontogenetic variation in Mapusaurus rosae (Dinosauria: Theropoda) and the probable role of heterocrony in carcharodontosaurid evolution. Palaeontol Z doi: 10.1007/s12542-014-0251-3}}</ref> Coria and Currie diagnosed ''Mapusaurus'' as follows: "''Mapusaurus'' n. gen. is a [[Carcharodontosauridae|carcharodontosaurid]] theropod whose [[skull]] differs from ''Giganotosaurus'' in having thick, rugose unfused nasals that are narrower anterior to the nasal/[[maxilla]]/[[lacrimal bone|lacrimal]] junction; larger extension of the [[Antorbital fenestra|antorbital fossa]] onto maxilla; smaller maxillary [[Fenestra (anatomy)|fenestra]]; wider bar (interfenestral strut) between antorbital and maxillary fenestrae; lower, flatter lacrimal [[horn (anatomy)|horn]]; transversely wider [[prefrontal]] in relation to lacrimal width; ventrolaterally curving lateral margin of the [[palpebral (bone)|palpebral]]; shallow [[interdental plate]]s; higher position of Meckelian canal; more posteriorly sloping anteroventral margin of [[dentary]]. ''Mapusaurus roseae'' is unique in that the upper [[quadratojugal]] process of [[jugal]] splits into two prongs; small anterior [[mylohyoid groove|mylohyoid]] [[foramen]] positioned above dentary contact with [[splenial]]; second and third [[metacarpal]]s fused; [[humerus]] with broad [[Anatomical terms of location#Proximal and distal|distal]] end and little separation between [[Condyle (anatomy)|condyle]]s; the [[Ilium (bone)#In dinosaurs|brevis fossa]] of the [[Ilium bone#In dinosaurs|ilium]] extends deeply into excavation dorsal to ischial peduncle. It also differs from ''Giganotosaurus'' in having [[cone (geometry)|conical]], slightly curving [[neck|cervical]] [[epipophyses]] that taper distally; axial posterior zygapohyses joined on midline; smaller and less elaborate prespinal [[lamina of the vertebral arch|lamina]] on midline of cervicals; remarkably sharp [[Dorsum (biology)|dorsal]] margin of cervical [[Vertebra#General structure|neural spines]]; tall, wider neural spines; curved ischiatic shaft; more slender [[fibula]]."<ref name="coria&currie2006"/> ==Discovery== [[File:Mapusaurus bones.png|thumb|Some ''Mapusaurus'' bones]] ''Mapusaurus'' was excavated between 1997 and 2001, by the Argentinian-Canadian Dinosaur Project, from an exposure of the [[Huincul Formation]] (Rio Limay Group, [[Cenomanian]]) at Canadon de Gato. It was described and named by [[paleontologists]] [[Rodolfo Coria]] and [[Phil Currie]] in 2006.<ref name="coria&currie2006"/> The name ''Mapusaurus'' is derived from the [[Mapuche]] word ''Mapu'', meaning 'of the Land' or 'of the Earth' and the [[Ancient Greek|Greek]] ''sauros'', meaning '[[lizard]]'. The [[type species]], ''Mapusaurus roseae'', is named for both the [[rose]]-colored rocks, in which the fossils were found and for [[Gordon Letwin|Rose Letwin]], who sponsored the expeditions which recovered these [[fossil]]s. The designated [[holotype]] for the [[genus]] and [[type species]], ''Mapusaurus roseae'', is an isolated right nasal (MCF-PVPH-108.1, Museo Carmen Funes, Paleontología de Vertebrados, Plaza Huincul, Neuquén). Twelve paratypes have been designated, based on additional isolated skeletal elements. Taken together, the many individual elements recovered from the ''Mapusaurus'' bone bed represent most of the skeleton.<ref name="coria&currie2006"/> hello YellowMonsterKilla10 huehuehue ==Paleobiology== [[File:Mapusaurus BW.jpg|thumb|left|Artist's impression]] The [[fossil]] remains of ''Mapusaurus'' were discovered in a [[bone bed]] containing at least seven individuals of various [[Ontogeny|growth stages]]. Coria and Currie speculated that this may represent a long term, possibly coincidental accumulation of carcasses (some sort of [[predator trap]]) and may provide clues about ''Mapusaurus'' behavior.<ref name="coria&currie2006"/> Other known [[theropod]] bone beds include the ''[[Allosaurus]]''-dominated [[Cleveland Lloyd Dinosaur Quarry]] of [[Utah]], an ''[[Albertosaurus]]'' bone bed from [[Alberta]] and a ''[[Daspletosaurus]]'' bone bed from [[Montana]]. [[File:Mapusaurus-skull-comparison.jpg|thumb|A skull comparison between two ''Mapusaurus roseae'' skulls]] Paleontologist Rodolfo Coria, of the [[Museo Carmen Funes]], contrary to his published article, repeated in a press-conference earlier suggestions that this congregation of fossil bones may indicate that ''Mapusaurus'' hunted in groups and worked together to take down large prey, such as the immense [[sauropod]] ''[[Argentinosaurus]]''.<ref name="AP1">Associated Press (2006). Details Revealed About Huge Dinosaurs. ABC News US. [http://abcnews.go.com/Technology/wireStory?id=1852246&page=1]</ref> If so, this would be the first substantive evidence of gregarious behavior by large theropods other than ''[[Tyrannosaurus]]'', although whether they might have hunted in organized packs (as wolves do) or simply attacked in a mob, is unknown. The authors interpreted the [[Sedimentary depositional environment|depositional environment]] of the Huincul Formation at the Canadon de Gato locality as a freshwater paleochannel deposit, "laid down by an ephemeral or seasonal stream in a region with arid or semi-arid climate".<ref name="coria&currie2006"/> This bone bed is especially interesting, in light of the overall scarcity of fossilized bone within the Huincul Formation. An ontogenetic study by Canale ''et al'' (2014)<ref>{{cite journal|last1=Canale|first1=Juan|title=Cranial ontogenetic variation in Mapusaurus roseae (Dinosauria: Theropoda) and the probable role of heterochrony in carcharodontosaurid evolution|journal=Palaeontol Z|date=September 24, 2014|url=http://www.researchgate.net/publication/276266912_Cranial_ontogenetic_variation_in_Mapusaurus_roseae_%28Dinosauria_Theropoda%29_and_the_probable_role_of_heterochrony_in_carcharodontosaurid_evolution|ref=Canale JI, Novas FE, Salgado L, Coria RA. 2014. Cranial ontogenetic variation in Mapusaurus rosae (Dinosauria: Theropoda) and the probable role of heterocrony in carcharodontosaurid evolution. Palaeontol Z doi: 10.1007/s12542-014-0251-3}}</ref> found that ''Mapusaurus'' displayed heterochrony, an evolutionary condition in which the animals may retain an ancestral characteristic during one stage of their life but lost it as they developed. In ''Mapusaurus'', the maxillary fenestrae are present in the younger individuals but gradually disappeared as they matured. ==Classification== [[Cladistic]] analysis carried out by Coria and Currie definitively showed that ''Mapusaurus'' is nested within the [[clade]] [[Carcharodontosauridae]]. The authors noted that the structure of the [[femur]] suggests a closer relationship with ''Giganotosaurus'' than either [[taxon]] shares with ''[[Carcharodontosaurus]]''. They created a new [[monophyletic]] taxon based on this relationship, the [[Family (biology)|subfamily]] [[Giganotosaurinae]], defined as all carcharodontosaurids closer to ''Giganotosaurus'' and ''Mapusaurus'' than to ''Carcharodontosaurus''. They tentatively included the genus ''[[Tyrannotitan]]'' in this new subfamily, pending publication of more detailed descriptions of the known specimens of that form.<ref name="coria&currie2006"/> The following cladogram after Novas ''et al.'', 2013, shows the placement of ''Acrocanthosaurus'' within Carcharodontosauridae.<ref name="sciencedirect.com">{{cite journal | doi = 10.1016/j.cretres.2013.04.001 | title=Evolution of the carnivorous dinosaurs during the Cretaceous: The evidence from Patagonia | journal=Cretaceous Research | date=2013 | volume=45 | pages=174–215 | first=Fernando E. | last=Novas}}</ref> {{clade| style=font-size:100%;line-height:80% |1={{clade |1=''[[Allosaurus]]'' |label2='''Carcharodontosauridae''' |2={{clade |1=''[[Neovenator]]'' |2=''[[Eocarcharia]]'' |3=''[[Concavenator]]'' |4={{clade |1=''[[Acrocanthosaurus]]'' |2={{clade |1=''[[Shaochilong]]'' |label2=Carcharodontosaurinae |2={{clade |1=''[[Carcharodontosaurus]]'' |label2=Giganotosaurini |2={{clade |1=''[[Tyrannotitan]]'' |2={{clade |1=''Mapusaurus'' |2=''[[Giganotosaurus]]'' }} }} }} }} }} }} }} }} ==Paleoecology== [[File:Mapusaurus skulls.jpg|thumb|Reconstructed skulls of adult and juvenile]] As previously mentioned, the Huincul Formation is thought to represent an arid environment with ephemeral or seasonal streams. The age of this formation is estimated at 97-94 mya. The dinosaur record is considered sparse here. ''Mapusaurus ''shared its environment with sauropods ''Argentinosaurus ''(one of the largest sauropods, if not the largest), and ''[[Cathartesaura]]''. [[Abelisauroidea|Abelisauroid]] theropods ''[[Skorpiovenator]]'' and ''[[Ilokelesia]]'' also lived in the region.<ref>Sánchez, Maria Lidia; Heredia, Susana & Calvo, Jorge O. (2006): Paleoambientes sedimentarios del Cretácico Superior de la Formación Plottier (Grupo Neuquén), Departamento Confluencia, Neuquén [Sedimentary paleoenvironments in the Upper Cretaceous Plottier Formation (Neuquen Group), Confluencia, Neuquén]. Revista de la Asociación Geológica Argentina 61(1): 3-18. PDF fulltext</ref> ==References== {{Wikispecies}}<ref>Canale JI, Novas FE, Salgado L, Coria RA. 2014. Cranial ontogenetic variation in Mapusaurus rosae (Dinosauria: Theropoda) and the probable role of heterocrony in carcharodontosaurid evolution. Palaeontol Z doi: 10.1007/s12542-014-0251-3</ref><ref>Eddy DR, Clarke JA (2011) New Information on the Cranial Anatomy of Acrocanthosaurus atokensis and Its Implications for the Phylogeny of Allosauroidea (Dinosauria: Theropoda). PLoS ONE 6(3): e17932. doi:10.1371/journal.pone.0017932</ref> {{Portal|Dinosaurs}} {{Reflist}} ==External links== *[http://news.nationalgeographic.com/news/2006/04/0417_060417_large_dino.html Meat-Eating Dinosaur Was Bigger Than T. Rex.] National Geographic News. *"[http://www.miketaylor.org.uk/dino/faq/s-size/predator/index.html What were the longest/heaviest predatory dinosaurs?]". Mike Taylor. The Dinosaur FAQ. August 27, 2002. (Named as Unnamed Argentinian Carcharodontosaurine) *"[And the Largest Theropod is... http://dml.cmnh.org/2003Jul/msg00355.html]". The Dinosaur Mailing List Archives. Retrieved 21 March 2010 (Named as Undescribed Carcharodontosaurine) {{Allosauroidea}} [[Category:Carnosaurs]] [[Category:Cretaceous dinosaurs]] [[Category:Dinosaurs of South America]]'