Editing Torvosaurus (section)

== Systematics and classification ==
[[File:Complete skeleton of Torvosaurus.jpg|thumb|''Torvosaurus'' sp. in Japan]]
When first described in 1979 by Galton and Jensen,<ref name="galt79">P. M. Galton and J. A. Jensen. 1979. [https://www.researchgate.net/publication/272152788_A_new_large_theropod_dinosaur_from_the_Upper_Jurassic_of_Colorado A new large theropod dinosaur from the Upper Jurassic of Colorado] {{Webarchive|url=https://web.archive.org/web/20210709182839/https://www.researchgate.net/publication/272152788_A_new_large_theropod_dinosaur_from_the_Upper_Jurassic_of_Colorado |date=July 9, 2021 }}. Brigham Young University Geology Studies 26(1):1–12</ref> ''Torvosaurus'' was classified as a [[Megalosauridae|megalosaurid]], which is the current consensus.<ref name="Carrano2012"/> It was later assigned to [[Carnosauria]] by [[Ralph Molnar]] ''et al.'' in 1990,<ref>R. E. Molnar, S. M. Kurzanov, and Z. Dong. 1990. "Carnosauria". In: D. B. Weishampel, H. Osmólska, and P. Dodson (eds.), ''The Dinosauria''. University of California Press, Berkeley</ref> then to a basal position in [[Megalosauroidea|Spinosauroidea]] by [[Oliver Walter Mischa Rauhut]] in 2003,<ref>O. W. M. Rauhut. 2003. The interrelationships and evolution of basal theropod dinosaurs. Special Papers in Palaeontology 69:1–213</ref> and to a very basal position in [[Tetanurae]] by [[Thomas R. Holtz Jr.|Thomas Holtz]] in 1994.<ref>T.R. Holtz, 1994, "The phylogenetic position of the Tyrannosauridae: implications for theropod systematics", ''Journal of Paleontology'' '''68'''(5): 1100–1117</ref> All these assignments are not supported by present phylogenetic analysis.<ref name="Carrano2012"/> In 1985, Jensen assigned ''Torvosaurus'' to a family of its own, [[Megalosauridae|Torvosauridae]].<ref name="Jensen1985"/> Despite support for this concept by [[Paul Sereno]]<ref>P.C. Sereno, J.A. Wilson, H.C.E. Larsson, D.B. Dutheil, and H.-D. Sues, 1994, "Early Cretaceous dinosaurs from the Sahara", ''Science'' '''266'''(5183): 267–271</ref> and Mateus,<ref name=OMetal06/> it seems redundant because ''Torvosaurus'' is closely related to, and perhaps the [[sister species]] of, the earlier ''[[Megalosaurus]]'' within [[Megalosauridae|Megalosaurinae]].<ref name="Carrano2012"/> However, Torvosauridae may be used as an alternative name for Megalosauridae if ''Megalosaurus'' is considered an indeterminable ''nomen dubium''.<ref>P.C. Sereno, 1998, "A rationale for phylogenetic definitions, with application to the higher-level taxonomy of Dinosauria", ''Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen'' '''210'''(1): 41–83</ref> Though a close relative of ''Megalosaurus'', ''Torvosaurus'' is seemingly more advanced, or apomorphic. ''Torvosaurus''{{'}}s larger [[clade]], [[Megalosauridae]], is most commonly held as a [[basal (phylogenetics)|basal]] branch of [[Tetanurae]], considered to be less derived than [[carnosaur]]s or [[coelurosaur]]s and likely related to the [[spinosaurid]]s.<ref name="Carrano2012"/>
 
The following is a [[cladogram]] based on the phylogenetic analysis conducted by Carrano, Benson, and Sampson (2012) showing the relationships of ''Torvosaurus'':<ref name="Carrano2012">Carrano, M. T.; Benson, R. B. J.; Sampson, S. D. (2012). "The phylogeny of Tetanurae (Dinosauria: Theropoda)". Journal of Systematic Palaeontology 10 (2): 211–300. doi:10.1080/14772019.2011.630927</ref>

{{clade| style=font-size:90%;line-height:90%
|label1=[[Megalosauroidea]]
|1={{clade
   |1=[[Piatnitzkysauridae]] [[File:Piatnitzkysaurus floresi by Paleocolour.jpg|80px]]
   |label2=[[Megalosauria]]
   |2={{clade
      |1=''[[Streptospondylus]]''
      |2=[[Spinosauridae]] [[File:Spinosaurus aegyptiacus.png|70px]]
      |label3=[[Megalosauridae]]
      |3={{clade
         |label1=[[Eustreptospondylinae]]
         |1={{clade  
            |1=''[[Eustreptospondylus]]'' [[File:Eustrept1DB1 (Flipped).jpg|80px]] }}
         |2={{clade
            |label1=[[Megalosaurinae]]
            |1={{clade
               |1=''[[Duriavenator]]'' [[File:Duriavenator NT (Flipped).jpg|80px]]
               |2={{clade
                  |1=''[[Megalosaurus]]'' [[File:Megalosaurus silhouette by Paleogeek.svg|80px]]
                  |2='''''Torvosaurus''''' [[File:Torvosaurus tanneri Reconstruction (Flipped).png|80px]] }} }}
            |label2=[[Afrovenatorinae]]
            |2={{clade
               |1=''[[Afrovenator]]'' [[File:Afrovenator_Abakensis_by_PaleoGeek.jpg|80px]]
               |2={{clade
                  |1=''[[Dubreuillosaurus]]'' [[File:Dubreuillosaurus NT Flipped.png|80px]]
                  |2=''[[Magnosaurus]]'' [[File:Magnosaurus (Flipped).jpg|80px]] }}
               |3={{clade
                  |1=''[[Leshansaurus]]''
                  |2=''[[Piveteausaurus]]'' }} }} }} }} }} }} }}

=== Distinguishing anatomical features ===
[[File:Torvosaurus gurneyi vertebra.png|thumb|upright|Caudal vertebra of ''T. gurneyi'']]

According to Carrano ''et al.'' (2012), ''Torvosaurus'' can be distinguished based on the following characteristics:<ref>Carrano, Benson and Sampson, 2012. The phylogeny of Tetanurae (Dinosauria: Theropoda). Journal of Systematic Palaeontology. 10(2), 211–300</ref>
* The presence of a very shallow [[maxilla]]ry [[fossa (anatomy)|fossa]] (it lacks a ''fenestra maxillaris'' piercing the bone wall)
* The presence of fused interdental plates
* The pneumatic fossae in the posterior dorsal and the anterior caudal vertebrae centra being expanded to form enlarged, deep openings
* The puboischiadic plate being highly ossified (the paired bony plates of both sides connect and close off the entire underside of the pelvis, a very basal trait that Galton & Jensen saw as an indication that Theropoda was [[Polyphyly|polyphyletic]], with Carnosauria having independently evolved from carnivorous [[Plateosauridae|Prosauropoda]])<ref name=galt79/>
* A distal expansion of the [[ischium]] shaft with a prominent lateral midline crest and an ovalur outline when examined in lateral view
* The cervical vertebrae are [[Vertebral column#Classification|opisthocoelous]] with a pronounced flat rim around the anterior ball (according to Rauhut, 2000)
* A transverse [[fenestra]] is situated in the neural arch of the dorsal vertebrae in front of the [[Hyposphene-hypantrum articulation|hyposphene]] (according to Rauhut, 2000)<ref>Rauhut, 2000. The interrelationships and evolution of basal theropods (Dinosauria, Saurischia). Ph.D. dissertation, Univ. Bristol [U.K.], 1–440.</ref>