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'{{Short description|Extinct genus of dinosaurs}} {{Italic title}} {{speciesbox | name = ''Megaraptor'' | fossil_range = [[Late Cretaceous]], [[Turonian]]–[[Coniacian]]<ref name="Juan D. Porfiri, Fernando E. Novas, Jorge O. Calvo, Federico L. Agnolín, Martín D. Ezcurra and Ignacio A. Cerda 2014 35–55"/> | image = Megaraptor hand.jpg | image_caption = Reconstructed hand | genus = Megaraptor | parent_authority = [[Fernando Novas|Novas]] 1998 | species = namunhuaiquii | authority = Novas 1998 }} '''''Megaraptor''''' ("giant thief") is a [[genus]] of large [[Theropoda|theropod]] [[dinosaur]] that lived in the ages of the [[Late Cretaceous]].<ref name="novas1998"/><ref name="calvoetal2004"/> Its fossils have been discovered in the Patagonian [[Portezuelo Formation]] of [[Argentina]], That is in South America. Initially thought to have been a giant [[dromaeosaur]]-like [[coelurosaur]], it was classified as a [[Neovenatoridae|neovenatorid]] [[Allosauroidea|allosauroid]] in previous phylogenies, but more recent phylogeny and discoveries of related [[megaraptora]]n genera has placed it as either a basal [[Tyrannosauroidea|tyrannosauroid]] or a basal [[Coelurosauria|coelurosaur]].<ref>{{Cite web | url=https://www.paleowire.com/just-out-a-new-megaraptoran-theropod-dinosaur-from-the-upper-cretaceous-bajo-de-la-carpa-formation-of-northwestern-patagonia-cretaceous-research/ | title=Just out &#124; A new megaraptoran theropod dinosaur from the Upper Cretaceous Bajo de la Carpa Formation of northwestern Patagonia @ Cretaceous Research}}</ref> ==Description== [[File: Megaraptor namunhuaiquii size chart.png|thumb|Size comparison.]] [[File:Megaraptor namunhuaiquii.jpg|left|thumb|Hypothetical life restoration of an adult]] [[File:Megaraptor bust.png|thumb|left|''Megaraptor'' head reconstruction based on the juvenile skull]] ''Megaraptor'' was initially described as a giant [[Dromaeosauridae|dromaeosaur]], known primarily from a single claw (about 30&nbsp;cm long) that resembled the sickle-shaped foot claw of dromaeosaurids.<ref name="novas1998">{{cite journal | last1 = Novas | first1 = F.E. | year = 1998 | title = ''Megaraptor namunhuaiquii'', gen. et sp. nov., a large-clawed, Late Cretaceous theropod from Patagonia | journal = Journal of Vertebrate Paleontology | volume = 18 | pages = 4–9 | doi = 10.1080/02724634.1998.10011030 }}</ref> The discovery of a complete front limb, however, showed that this giant claw actually came from the first finger of the hand. In 2010, [[Gregory S. Paul]] estimated its length at {{convert|8|m|ft}}, its weight at {{convert|1|tonne|lbs}}.<ref>Paul, G.S., 2010, ''The Princeton Field Guide to Dinosaurs'', Princeton University Press p. 99</ref> The hands were unusually elongated, bearing sickle-shaped claws even more recurved than those of [[Spinosauridae|spinosaurids]].<ref name="calvoetal2007">Calvo, J.O., Porfiri, J.D., González-Riga, B.J., and Kellner, A.W. (2007) "A new Cretaceous terrestrial ecosystem from Gondwana with the description of a new sauropod dinosaur". ''Anais da Academia Brasileira de Ciências'', '''79'''(3): 529–41.[https://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=pubmed&dopt=AbstractPlus&list_uids=17768539]</ref> ==Classification== The hand is quite distinct from other basal [[Tetanurae|tetanurans]], so it was not initially clear whether ''Megaraptor'' was an allosaurid, a carcharodontosaurid, a spinosauroid, or something else entirely.<ref name="calvoetal2004">{{cite journal | last1 = Calvo | first1 = J. O. | last2 = Porfiri | first2 = J.D. | last3 = Veralli | first3 = C. | last4 = Novas | first4 = F.E. | last5 = Poblete | first5 = F. | year = 2004 | title = Phylogenetic status of ''Megaraptor namunhuaiquii'' Novas based on a new specimen from Neuquén, Patagonia, Argentina | journal = [[Ameghiniana]] | volume = 41 | pages = 565–575 }}</ref> Subsequent studies, as well as the identification of close relatives with similar large claws on the forelimbs (see below), helped identify ''Megaraptor'' as a highly advanced and lightly built allosauroid, and a member of the family [[Neovenatoridae]].<ref name=bensonetal2010>{{cite journal | last1 = Benson | first1 = R.B.J. | last2 = Carrano | first2 = M.T | last3 = Brusatte | first3 = S.L. | year = 2010 | title = A new clade of archaic large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to the latest Mesozoic | journal = Naturwissenschaften | volume = 97 | issue = 1| pages = 71–78 | doi = 10.1007/s00114-009-0614-x | pmid=19826771 | bibcode=2010NW.....97...71B| s2cid = 22646156 }}</ref> More recent studies have proposed that ''Megaraptor'' and its kin are actually [[Tyrannosauroidea|tyrannosauroids]]<ref name="novas2012"/> or [[megalosauroidea|spinosauroids]]<ref name="Holtz2012">{{cite book|last=Holtz|first=T.R. Jr.|year=2012|title=Dinosaurs: The Most Complete, Up-to-date Encyclopedia for Dinosaur Lovers of All Ages|publisher=Random House Books for Young Readers|pages=[https://archive.org/details/dinosaursmostcom00holt/page/95 95–96]|isbn=978-0-375-82419-7|url-access=registration|url=https://archive.org/details/dinosaursmostcom00holt/page/95}}</ref> as opposed to [[Allosauroidea|allosauroids]].<ref name="novas2012">{{cite journal |author1=F. E. Novas |author2=F. L. Agnolín |author3=M. D. Ezcurra |author4=J. I. Canale |author5=J. D. Porfiri | year= 2012 | title=Megaraptorans as members of an unexpected evolutionary radiation of tyrant-reptiles in Gondwana | url=http://www.ameghiniana.org.ar/index.php/ameghiniana/article/view/868/1618 | journal=Ameghiniana | volume=49 | issue=Suppl | pages=R33 }}</ref> A juvenile specimen described in 2014 has provided more evidence towards ''Megaraptor'' being a primitive tyrannosauroid.<ref name="Porfiri2014">{{cite journal | author=Porfiri, J. D., Novas, F. E., Calvo, J. O., Agnolín, F. L., Ezcurra, M. D. & Cerda, I. A.| year= 2014 | title=Juvenile specimen of Megaraptor (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation |journal=Cretaceous Research| volume=51| pages=35–55 | doi=10.1016/j.cretres.2014.04.007| last2= Novas | last3= Calvo | last4= Agnolín | last5= Ezcurra | last6= Cerda }}</ref> The discovery of ''[[Gualicho]]'' indicates that ''Megaraptor'' may not be a tyrannosauroid, but either an allosauroid or basal coelurosaur.<ref>{{Cite journal | doi=10.1371/journal.pone.0157793| pmid=27410683| pmc=4943716|bibcode = 2016PLoSO..1157793A|title = An Unusual New Theropod with a Didactyl Manus from the Upper Cretaceous of Patagonia, Argentina| journal=PLOS ONE| volume=11| issue=7| pages=e0157793|last1 = Apesteguía|first1 = Sebastián| last2=Smith| first2=Nathan D.| last3=Juárez Valieri| first3=Rubén| last4=Makovicky| first4=Peter J.| year=2016| doi-access=free}}</ref> When first discovered and prior to publication, the [[Spinosauridae|spinosaurid]] ''[[Baryonyx]]'' was also reported to be a dromaeosaurid, and the allosauroid ''[[Chilantaisaurus]]'' was reported to be a possible spinosaurid, both based on the large hand claws. [[File:Megaraptor claw cast with scale.JPG|thumb|Claw cast with a ruler for scale]] The cladogram shown below follows an analysis by Porfiri ''et al.'', 2014.<ref name="Juan D. Porfiri, Fernando E. Novas, Jorge O. Calvo, Federico L. Agnolín, Martín D. Ezcurra and Ignacio A. Cerda 2014 35–55">{{Cite journal|author1=Juan D. Porfiri |author2=Fernando E. Novas |author3=Jorge O. Calvo |author4=Federico L. Agnolín |author5=Martín D. Ezcurra |author6=Ignacio A. Cerda |year=2014 |title=Juvenile specimen of ''Megaraptor'' (Dinosauria, Theropoda) sheds light about tyrannosauroid radiation |journal=Cretaceous Research |volume=51 |pages=35–55 |doi=10.1016/j.cretres.2014.04.007 }}</ref> {{Clade/Megaraptora1|Megaraptora1=Aoniraptor}} == References ==<!-- Anais da Academia Brasileira de Ciências (2007) 79(3): 529-541 --> {{Reflist}} == External links == * [https://www.sciencedaily.com/releases/2008/06/080613111410.htm Science Daily] {{Theropoda|A.}} {{Taxonbar|from=Q131540}} {{Portal bar|Dinosaurs|Paleontology|Cretaceous}} [[Category:Megaraptorans]] [[Category:Coniacian life]] [[Category:Turonian life]] [[Category:Late Cretaceous dinosaurs of South America]] [[Category:Cretaceous Argentina]] [[Category:Fossils of Argentina]] [[Category:Portezuelo Formation]] [[Category:Fossil taxa described in 1998]] [[Category:Taxa named by Fernando Novas]]'