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Temporal range: Middle Jurassic-Early Cretaceous, 175.6–135 Ma
Sinraptor dongi.jpg
Sinraptor dongi, Royal Tyrrell Museum
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: Saurischia
Suborder: Theropoda
Infraorder: Carnosauria
Superfamily: Allosauroidea
Family: Metriacanthosauridae
Paul, 1988
Type species
Megalosaurus parkeri
Huene, 1923
  • Sinraptoridae Currie & Zhao, 1993

Metriacanthosauridae is an extinct family of carnivorous allosauroid theropod dinosaurs.[1] They tended to be large predators, some growing to sizes of 10 metres (33 ft). Metriacanthosaurids are carnosaurs, and many were initially classified within Megalosauridae or Allosauridae. A gigantic tooth belonging to what most likely is a giant sinraptorid has been described by Xu and Clarke in 2008.[2]


Metriacanthosaurids share the following unambiguous synapomorphies among allosauroids:[1]

  • A short or absent anterior ramus of the maxilla (also found in Carcharodontosaurids and Piatnitzkysaurids).
  • The laterosphenoid articulated on the frontal and postorbital.
  • A squamosal without constriction of the lower temporal fenestra. (also found in megalosauroids)
  • A flange on the squamosal covering the quadrate head laterally.
  • A well-defined longitudinal groove on the lateral side of the dentary housing a row of neurovascular foramina.
  • Broad, well developed spinopostzygapophyseal lamina on the axis.
  • A manus shorter than the forearm.
  • Subrectangular and sheet-like neural spines of middle caudal vertebrae.
  • A manus without digit V or the phalanges of digit IV (also found in Neovenatorids).
  • A heart-shaped cross section of the ilium's paired midshafts (also found in Coelophysids).
  • Fused distal end of the ischium (also found in Neovenatorids and basal tetanurans).

Metriacanthosaurines share the following synapomorphies among metriacanthosaurids:[1]


Cladistically, Sinraptoridae was latest defined in 2005 by Paul Sereno as the most inclusive monophyletic group that contains Sinraptor dongi and all species closer related to Sinraptor than to either Allosaurus fragilis, Carcharodontosaurus saharicus, or the house sparrow (Passer domesticus).[3]

Carrano, Benson & Sampson (2012) noted that the name Metriacanthosauridae should be used as it has priority over Sinraptoridae.[1] Furthermore, they named a new subfamily Metriacanthosaurinae to include all metriacanthosaurids more closely related to Metriacanthosaurus than to Yangchuanosaurus. A much larger phylogenetic analysis found the basal megalosauroid Xuanhanosaurus (according to Benson et al., 2010)[4] as the basalmost metriacanthosaurid. Both Poekilopleuron and Lourinhanosaurus were recovered outside the family, and many taxa within the Metriacanthosauridae were in polytomy. However, the position of Xuanhanosaurus and Poekilopleuron is very unstable, and their exclusion from the analysis gave more resolved and stable cladogram. The cladogram presented here follows that study.[1]





Other coelurosaurians







Yangchuanosaurus zigongensis

CV 00214

Yangchuanosaurus shangyouensis




"Sinraptor" hepingensis

Sinraptor dongi



  1. ^ a b c d e 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. 
  2. ^ Xu, X., Clark, J.M. (2008): The presence of a gigantic theropod in the Jurassic Shishugou Formation, Junggar Basin, western China. Vertebrata PalAsiatica, 46: 158-160.
  3. ^ Sereno, Paul. "Sinraptoridae". Taxon Search. Retrieved 12 December 2010. 
  4. ^ Benson, R.B.J., Carrano, M.T and Brusatte, S.L. (2010). "A new clade of archaic large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to the latest Mesozoic". Naturwissenschaften. 97 (1): 71–78. Bibcode:2010NW.....97...71B. doi:10.1007/s00114-009-0614-x. PMID 19826771.  Supporting Information

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