Albertaceratops

Albertaceratops (meaning "Alberta horned face") was a genus of centrosaurine horned dinosaur from the middle Campanian-age Upper Cretaceous Oldman Formation of Alberta, Canada.[1]

Albertaceratops
Temporal range: Late Cretaceous,
Skull in Philip J. Currie Dinosaur Museum
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Order: †Ornithischia
Suborder: †Ceratopsia
Family: †Ceratopsidae
Subfamily: †Centrosaurinae
Genus: †Albertaceratops
Ryan, 2007
Species:
†A. nesmoi
Binomial name
†Albertaceratops nesmoi
Ryan, 2007

Description

Restoration

Albertaceratops is unusual in combining long brow horns with an otherwise centrosaurine skull, as centrosaurines normally possess short brow horns. Over its nose was a bony ridge, and on its frill were two large outwardly-projecting hooks.[1] Its size has been estimated at 5.8 metres (19 ft) and 3,500 kilograms (7,700 lb).[2]

Discovery and naming

Skull of the Albertaceratops nesmoi holotype, TMP 2001.26.1

Albertaceratops is known from a single complete skull (TMP.2001.26.1) found in August 2001 and skull and postcranial fragments. A phylogenetic analysis carried out by its describer, Michael J. Ryan, found it to be the most basal centrosaurine.[1] Additional specimens were reported from a bonebed in the Judith River Formation of Montana, which is equivalent to the Oldman Formation and differentiated only by the Canada–US border. However, further study showed these remains to come from a different centrosaurine, Medusaceratops. Both ceratopsids lived during the same time period, about 77.5 million years ago.[3]

The specific name, A. nesmoi, is derived from the name of Cecil Nesmo, a rancher living in Manyberries, Alberta, a town of less than 100 people located 71 km south of Medicine Hat. The rancher was thus honored in recognition of his efforts to aid fossil hunters.[1]

Classification

Coronosaurus and Albertaceratops in environment
Size of Albertaceratops compared to a human

The cladogram presented below follows a phylogenetic analysis by Chiba et al. (2017), which included a systematic re-evaluation of Medusaceratops lokii:[4]

Centrosaurinae
 
 

Diabloceratops eatoni

 
 

Machairoceratops cronusi

 
 
 
Nasutoceratopsini
 

Avaceratops lammersi (ANSP 15800)

 
 

MOR 692

 
 

CMN 8804

 
 

Nasutoceratops titusi

 
 

Malta new taxon

 
 
 
 

Xenoceratops foremostensis

 
 
 
 

Sinoceratops zhuchengensis

 
 

Wendiceratops pinhornensis

 
 
 

Albertaceratops nesmoi

 
 

Medusaceratops lokii

 
Eucentrosaura
Centrosaurini
 
 

Rubeosaurus ovatus

 
 

Styracosaurus albertensis

 
 
 
 

Coronosaurus brinkmani

 
 
 

Centrosaurus apertus

 
 

Spinops sternbergorum

 
 
 
 
Pachyrhinosaurini
 

Einiosaurus procurvicornis

 
Pachyrostra
 

Achelousaurus horneri

 
 
 

Pachyrhinosaurus canadensis

 
 
 

Pachyrhinosaurus lakustai

 
 

Pachyrhinosaurus perotorum

 
 
 
 
 
 
 
 
 
 

See also

References

  1. Ryan, Michael J. (2007). "A New Basal Centrosaurine Ceratopsid from the Oldman Formation, Southeastern Alberta". Journal of Paleontology. 81 (2): 376–396. doi:10.1666/0022-3360(2007)81[376:ANBCCF]2.0.CO;2. ISSN 0022-3360.
  2. Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 259
  3. Ryan, Michael J.; Russell, Anthony P., and Hartman, Scott. (2010). "A New Chasmosaurine Ceratopsid from the Judith River Formation, Montana", In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, and David A. Eberth (eds), New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, Indiana University Press, 656 pp. ISBN 0-253-35358-0.
  4. Kentaro Chiba; Michael J. Ryan; Federico Fanti; Mark A. Loewen; David C. Evans (2018). "New material and systematic re-evaluation of Medusaceratops lokii (Dinosauria, Ceratopsidae) from the Judith River Formation (Campanian, Montana)". Journal of Paleontology. in press (2): 272–288. doi:10.1017/jpa.2017.62. S2CID 134031275.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.