Chasmosaurinae

Chasmosaurines Temporal range: Late Cretaceous, 76.5–66 Ma PreЄ Є O S D C P T J K Pg N
Chasmosaurus belli skeleton, Royal Tyrrell Museum of Palaeontology
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Dinosauria
Order:	†Ornithischia
Family:	†Ceratopsidae
Subfamily:	†Chasmosaurinae Lambe, 1915
Type species
†Chasmosaurus belli Lambe, 1902
Subgroups
See text.

Chasmosaurinae is a subfamily of ceratopsid dinosaurs. Triceratops is a well-known example. They were one of the most successful groups of herbivores of their time. Chasmosaurines appeared in the early Campanian, and became extinct, along with all other non-avian dinosaurs, during the Cretaceous–Paleogene extinction event. Broadly, the most distinguishing features of chasmosaurinae are prominent brow horns and long frills lacking long spines; centrosaurines generally had short brow horns and relatively shorter frills, and often had long spines projecting from their frills. Chasmosaurines are currently known definitively from rocks in western Canada, the western United States, and northern Mexico.

Genera

• Family Ceratopsidae
  • Subfamily Chasmosaurinae
    • Agujaceratops - (Texas, USA)
    • Anchiceratops - (Alberta, Canada)
    • Arrhinoceratops - (Alberta, Canada)
    • Bravoceratops - (Texas, USA)
    • Chasmosaurus - (Alberta, Canada)
    • Coahuilaceratops - (Coahuila, Mexico)
    • ? Dysganus - (Montana, USA)
    • Judiceratops - (Montana, USA)
    • Kosmoceratops - (Utah, USA)
    • Medusaceratops - (Montana, USA)
    • Mercuriceratops - (Montana, USA & Alberta, Canada)^[1]
    • Mojoceratops - (Alberta & Saskatchewan, Canada)
    • Pentaceratops - (New Mexico, USA)^[2]
    • Spiclypeus - (Montana, USA)
    • Utahceratops - (Utah, USA)
    • Vagaceratops - (Alberta, Canada)
    • Tribe Triceratopsini
      • Agathaumas - (Wyoming, USA)
      • Eotriceratops - (Alberta, Canada)
      • Ojoceratops - (New Mexico, USA)^[3]
      • Polyonax - (Colorado, USA)
      • Regaliceratops - (Alberta, Canada)
      • Tatankaceratops - (South Dakota, USA)
      • Titanoceratops - (New Mexico, USA)
      • Torosaurus - (Wyoming, Montana, South Dakota, North Dakota, & Utah, USA & Saskatchewan, Canada)
      • Triceratops - (Montana & Wyoming, USA & Saskatchewan & Alberta, Canada)

Below is the phylogeny of Brown et al.^[4]

Ceratopsidae	Centrosaurinae Chasmosaurinae Vagaceratops Kosmoceratops Chasmosaurus belli Chasmosaurus russeli Mojoceratops Agujaceratops Utahceratops Pentaceratops Bravoceratops Coahuilaceratops Anchiceratops Arrhinoceratops Triceratopsini Regaliceratops Eotriceratops Ojoceratops Titanoceratops Nedoceratops Torosaurus latus Torosaurus utahensis Triceratops horridus Triceratops prorsus

See also

• Timeline of ceratopsian research

References

1. Ryan, M. J.; Evans, D. C.; Currie, P. J.; Loewen, M. A. (2014). "A new chasmosaurine from northern Laramidia expands frill disparity in ceratopsid dinosaurs". Naturwissenschaften. doi:10.1007/s00114-014-1183-1.
2. Spencer G. Lucas, Robert M. Sullivan and Adrain P. Hunt (2006). Re-evaluation of Pentaceratops and Chasmosaurus (Ornithischia: Ceratopsidae) in the Upper Cretaceous of the Western Interior. p. 4.
3. Michael J. Ryan,Brenda J. Chinnery-Allgeier (n.d.). New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium. Royall Tyrell Museum. p. 500.
4. Brown, Caleb M.; Henderson, Donald M. (June 4, 2015). "A new horned dinosaur reveals convergent evolution in cranial ornamentation in ceratopsidae". Current Biology (online). doi:10.1016/j.cub.2015.04.041.

External links

• 1.http://paleodb.org/cgi-bin/bridge.pl