Editing Allosaurus (section)

{{mergefrom|Epanterias|discuss=Talk:Allosaurus#Proposal to merge Epanterias into Allosaurus|date=March 2025}}
{{Short description|Extinct genus of carnosaurian theropod dinosaur}}
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{{Use American English|date=March 2024}}
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{{Automatic taxobox
| fossil_range = [[Late Jurassic]] ([[Kimmeridgian]] to [[Tithonian]]), {{Geological range|155|143.1}}
| image = Allosaurus SDNHM (1).jpg
| image_caption = Mounted ''A. fragilis'' skeleton cast, [[San Diego Natural History Museum]]
| image_upright = 1.15
| parent_authority = [[Othniel Marsh|Marsh]], [[1878 in paleontology|1878]]
| taxon = Allosaurus
| authority = Marsh, [[1877 in paleontology|1877]]
| type_species = {{extinct}}'''''Allosaurus fragilis'''''
| type_species_authority = Marsh, 1877
| subdivision_ranks = Other species
| subdivision_ref = 
| subdivision = *{{extinct}}'''''A. europaeus''''' <br/><small>[[Octávio Mateus|Mateus]] et al., [[2006 in paleontology|2006]]</small>
*{{extinct}}'''''A. jimmadseni''''' <br/><small>Chure & Loewen, [[2020 in archosaur paleontology|2020]]</small>
*{{extinct}}'''''A. anax''''' <br/><small>Danison et al., [[2024 in archosaur paleontology|2024]]</small>
| synonyms = {{collapsible list|bullets = true|title=<small>Genus synonymy</small>
|''[[Antrodemus]]''? <br/><small>[[Joseph Leidy|Leidy]], [[1870 in paleontology|1870]]</small>
|''[[Apatodon]]''? <br/><small>Marsh, [[1878 in paleontology|1878]]</small>
|''Creosaurus'' <br/><small>Marsh, [[1878 in paleontology|1878]]</small>
|''[[Epanterias]]''? <br/><small>[[Edward Drinker Cope|Cope]], 1878</small>
|''Labrosaurus'' <br/><small>Marsh, [[1879 in paleontology|1879]]</small>
|"Madsenius" <br/><small>[[Robert Bakker|Bakker]], [[1990 in paleontology|1990]]</small>
|"Wyomingraptor" <br/><small>Bakker, [[1997 in paleontology|1997]]</small>
}}
}}

'''''Allosaurus''''' ({{IPAc-en|ˌ|æ|l|ə|ˈ|s|ɔːr|ə|s}})<ref>{{cite Merriam-Webster|Allosaurus}}</ref><ref>{{cite Dictionary.com|Allosaurus}}</ref> is an extinct [[genus]] of large [[theropoda|theropod]] dinosaur that lived 155 to 145&nbsp;million years ago during the [[Late Jurassic]] [[Geologic time scale|period]] ([[Kimmeridgian]] to late [[Tithonian]] [[Geologic time scale|ages]]). The name "''Allosaurus''" means "different lizard", alluding to its unique (at the time of its discovery) concave [[Glossary of dinosaur anatomy#vertebrae|vertebrae]]. The first fossil remains that could definitively be ascribed to this [[genus]] were described in [[1877 in paleontology|1877]] by [[Othniel Charles Marsh]]. The genus has a very complicated [[Taxonomy (biology)|taxonomy]] and includes at least three valid [[species]], the best known of which is ''A. fragilis''. The bulk of ''Allosaurus'' remains have come from North America's [[Morrison Formation]], with material also known from the [[Alcobaça Formation]] and [[Lourinhã Formation]] in Portugal with teeth known from Germany. It was known for over half of the 20th century as ''[[Antrodemus]]'', but a study of the abundant remains from the [[Cleveland-Lloyd Dinosaur Quarry]] returned the name "''Allosaurus''" to prominence. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles.

''Allosaurus'' was a large [[biped]]al predator for its time. Its skull was light, robust, and equipped with dozens of sharp, [[serrated]] teeth. It averaged {{convert|8.5|m|sp=us}} in length for ''A. fragilis'', with the largest specimens estimated as being {{convert|9.7|m|sp=us}} long. Relative to the large and powerful legs, its three-fingered hands were small and the body was balanced by a long, muscular tail. It is classified in the family [[Allosauridae]]. As the most abundant large predator of the Morrison Formation, ''Allosaurus'' was at the top of the food chain and probably preyed on large herbivorous dinosaurs such as [[ornithopod]]s, [[stegosaurid]]s, and [[sauropod]]s. It is also possible that it hunted other predators. Scientists have debated whether ''Allosaurus'' had cooperative [[social behavior]] and hunted in packs or was a solitary predator that form congregations, with evidence supporting either side.