Open Paleo

Proceratosaurus

Huene, 1926 proh-suh-RAT-oh-SAW-ruhs /proʊsəˌrætoʊˈsɔːrəs/

From Greek pro- (πρό, 'before' or 'precursor of') prefixed to Ceratosaurus, as it was originally thought to be closely related to or ancestral to Ceratosaurus; meaning 'before Ceratosaurus'

168.2–165.3 million years ago Bathonian, Middle Jurassic
Middle Jurassic stages

Proceratosaurus is a genus of theropod dinosaur that lived during the Middle Jurassic in what is now England. The holotype and only known specimen consists of a mostly complete skull with an accompanying lower jaw and a hyoid bone, found near Minchinhampton, a town in Gloucestershire. It was originally described in 1910 as a species of Megalosaurus, M. bradleyi, but was moved to its own genus, Proceratosaurus, in 1926. The genus was named for its supposed close relationship with Ceratosaurus, later shown to be erroneous, due to perceived resemblance of Proceratosaurus's incomplete cranial crest to Ceratosaurus's nasal horn.

Diagnosis

  1. Four premaxillary teeth with peculiar lateral flat longitudinal folds unknown elsewhere
  2. Eighteen maxillary teeth (including two gaps), greater number than in Megalosaurus or Ceratosaurus
  3. Lateral temporal opening relatively broad in whole height, differing from Megalosaurids
  4. External narial openings differing in shape from Megalosaurus and Ceratosaurus
  5. Ascending process of maxilla distinctly different in shape and breadth from Megalosaurids
  6. Comb-like nasal prominence unknown elsewhere in dinosaurs

Species

Proceratosaurus bradleyi Huene, 1926

Type species

Named for F. Lewis Bradley, who discovered the holotype skull during excavation for a reservoir near Minchinhampton, England.

Holotype
BMNH R4860 , Natural History Museum
Material
Skull, incomplete in upper half
Horizon
Great Oolite Group, Bathonian, Middle Jurassic , 168.2–165.3 million years ago
Locality
Minchinhampton reservoir, Gloucestershire, United Kingdom Huene (1926) and Rauhut and colleagues (2010) give the horizon only as the Great Oolite of Minchinhampton. Carrano and colleagues (2012) assign it to the White Limestone Formation and Naish and Cau (2022) to the Taynton Limestone Formation, neither stating a basis.

References

  1. Rauhut, O. W. M.; Milner, A. C.; Moore-Fay, S. (2010). Cranial osteology and phylogenetic position of the theropod dinosaur Proceratosaurus bradleyi (Woodward, 1910) from the Middle Jurassic of England. Zoological Journal of the Linnean Society 158(1): 155-195. doi:10.1111/j.1096-3642.2009.00591.x

    Redescribes the holotype and gives the horizon as "Great Oolite, Late Bathonian, Middle Jurassic".

    rauhut2010a
  2. Naish, D.; Cau, A. (2022). The osteology and affinities of Eotyrannus lengi, a tyrannosauroid theropod from the Wealden Supergroup of southern England. PeerJ 10: e12727. PeerJ. doi:10.7717/peerj.12727

    Places the taxon in "the Bathonian Taynton Limestone Formation", citing Rauhut and colleagues (2010).

    naish2022a
  3. Huene, F. V. (1926). On several known and unknown reptiles of the order Saurischia from England and France. Annals and Magazine of Natural History, series 9 17: 473-489. doi:10.1080/00222932608633437 huene1926a
  4. 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. Informa UK Limited. doi:10.1080/14772019.2011.630927

    Assigns the Minchinhampton Reservoir material to the White Limestone Formation of the Great Oolite Group.

    carrano2012a
  5. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the hip height estimate, and the appearance features.

    jones2026c