Open Paleo

Centrosaurus

Lambe, 1905 SEN-troh-SOR-uhs /ˌsɛntroʊˈsɔːrəs/

From Greek kentron (κέντρον) meaning 'point' and Greek sauros (σαῦρος) meaning 'lizard'. Full meaning: 'pointed lizard', referring to the small hornlets along the margin of its frill.

83.6–72.2 million years ago Campanian, Late Cretaceous
Late Cretaceous stages

Centrosaurus is a genus of centrosaurine ceratopsid dinosaur from the Campanian age of the Late Cretaceous of Canada. Its remains have been found in the Dinosaur Park Formation, dating from 76.5 to 75.5 million years ago. The type and only species seen as valid today is Centrosaurus apertus.

Diagnosis

  1. Fontanelles of the crest included entirely within the parietal part of the expansion (not bounded laterally by the squamosal)
  2. Posterior border of crest bears a pair of greatly modified hooked epoccipital processes (large hook-like spurs of bone) on the hinder border
  3. Crest broadly expanded laterally, broader than long, with a robust transverse posterior bar that is concave in outline behind
  4. Squamosals confined to the antero-lateral edge of the frill, contributing little to its overall formation
  5. Large oval fontanelles one on either side of the median line, bounded behind by the transverse bar and laterally/anteriorly by thin side extensions

Species

Centrosaurus apertus Lambe, 1905

Type species

From Latin 'apertio' meaning 'an opening' or 'aperture', referring to the two large, open fenestrae in the frill that distinguish it from other ceratopsians.

Holotype
CMN 971 , Canadian Museum of Nature
Material
Large posterior squamoso-parietal crest (coalesced parietals) with associated nasal horn core.
Horizon
Belly River Group, Campanian, Late Cretaceous , 83.6–72.2 million years ago
Locality
Red Deer River, Alberta, Canada Hatcher and colleagues (1907) give the type as found "in the Belly River (Judith River) series of Red Deer River"; no source read places it in the Oldman or the Dinosaur Park Formation.

Synonyms of the genus

Name Type Reason
Eucentrosaurus junior objective Proposed as a replacement name when Centrosaurus was thought to be preoccupied by the stegosaur Kentrosaurus; the perceived conflict was later determined to be invalid.

References

  1. Hatcher, J. B.; Marsh, O. C.; Lull, R. S. (1907). The Ceratopsia. Monographs of the United States Geological Survey 49: 1-300. United States Geological Survey.

    Gives the type as found "in the Belly River (Judith River) series of Red Deer River, Alberta".

    hatcher1907a
  2. Lambe, L. M. (1905). On the squamoso-parietal crest of the horned dinosaurs Centrosaurus apertus and Monoclonius canadensis from the Cretaceous of Alberta. Proceedings and Transactions of the Royal Society of Canada, series 2 10(4): 1-9. lambe1905a
  3. Paul, G. S. (2024). The Princeton Field Guide to Dinosaurs (3rd ed.). Princeton University Press.

    Source of the appearance features.

    paul2024a