Iliosuchus
Temporal range: Bathonian
~168–166 Ma
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Drawing of BMNH R83
Photograph of BMNH R83
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Clade: Orionides
Clade: Avetheropoda
Clade: Coelurosauria
Genus: †Iliosuchus
Huene, 1932
Type species
Iliosuchus incognitus
Huene, 1932
Synonyms
  • Megalosaurus incognitus (von Huene, 1932 [originally Iliosuchus])

Iliosuchus (meaning "crocodile hipped") is a genus of theropod dinosaur known from Bathonian–age (168.3 – 166.1 mya) rocks of England. It was perhaps 2 metres (6.6 ft) long.[1]

History

The only known fossils of this genus are three ilia (BMNH R83, OUM J29780 and OUM J28971) from the Stonesfield Slate, Oxfordshire, England. From the holotype BMNH R83, which was discovered in 1880,[2] Friedrich von Huene described and named the only species, I. incognitus, in 1932.[3] The generic name is derived from the ilium and Greek Souchos, the crocodile god. The specific name means "unknown" in Latin. Another species, I. clevelandi, was proposed in 1976 by Peter Galton,[4] who assigned Stokesosaurus clevelandi to Iliosuchus, but this has found no acceptance among other researchers;[5] in 1980 Galton himself withdrew his opinion.[6]

Description

The Iliosuchus ilia, very small with a length of nine to ten centimetres, have a vertical supra–acetabular ridge on the surface, similar to tyrannosaurids and many other predatory dinosaurs belonging to the group Tetanurae, including Piatnitzkysaurus and Megalosaurus.[7] Such fragmentary and incomplete material is inadequate for accurate classification; nonetheless, Iliosuchus has sometimes been considered a tyrannosaurid ancestor. This is unlikely to be correct as the bones cannot be distinguished from small individuals of Megalosaurus, a megalosaurid. Whatever the case, Iliosuchus is not diagnostic and is therefore dubious.[7] If Iliosuchus incognitus is a tyrannosauroid, it would be a possible ancestor to Proceratosaurus, the earliest recognized tyrannosauroid, and would be the earliest of the tyrannosauroids.

See also

References

  1. ^ Holtz, Thomas R. Jr. (2008) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages Supplementary Information
  2. ^ Lomax, D. & Tamura, N. (2014). "Dinosaurs of the British Isles", Siri Scientific Press pg. 162 ISBN 9780957453050
  3. ^ F. v. Huene (1932). "Die fossile Reptil-Ordnung Saurischia, ihre Entwicklung und Geschichte", Monographien zur Geologie und Palaeontologie, serie 1 4(1-2): 1-361
  4. ^ P. M. Galton, (1976), "Iliosuchus, a Jurassic dinosaur from Oxfordshire and Utah", Palaeontology 19(3): 587-589
  5. ^ Benson, R.B.J. (2008). "New information on Stokesosaurus, a tyrannosauroid (Dinosauria: Theropoda) from North America and the United Kingdom". Journal of Vertebrate Paleontology. 28 (3): 732–750. doi:10.1671/0272-4634(2008)28[732:NIOSAT]2.0.CO;2. S2CID 129921557.
  6. ^ Galton, P.M.; Powell, H.P. (1980). "The ornithischian dinosaur Camptosaurus prestwichii from the Upper Jurassic of England". Palaeontology. 23: 411–443.
  7. ^ a b Benson, R.B.J. (2009). "An assessment of variability in theropod dinosaur remains from the Bathonian (Middle Jurassic) of Stonesfield and New Park Quarry, UK and taxonomic implications for Megalosaurus bucklandii and Iliosuchus incognitus." Palaeontology 52 857-877, [1]
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