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

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. Its size has been estimated at 5.8 metres (19 ft) and 3,500 kilograms (7,700 lb).

Discovery and naming

Albertaceratops skull
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. 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.

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.

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:

CentrosaurinaeDiabloceratops 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
Diabloceratops eatoni Machairoceratops cronusi
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
NasutoceratopsiniAvaceratops lammersi (ANSP 15800) MOR 692 CMN 8804 Nasutoceratops titusi Malta new taxon
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
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
Sinoceratops zhuchengensis Wendiceratops pinhornensis
Sinoceratops zhuchengensis
Wendiceratops pinhornensis
Albertaceratops nesmoi
Medusaceratops lokii
EucentrosauraCentrosaurini Rubeosaurus ovatus Styracosaurus albertensis Coronosaurus brinkmani Centrosaurus apertus Spinops sternbergorum Pachyrhinosaurini Einiosaurus procurvicornis Pachyrostra Achelousaurus horneri Pachyrhinosaurus canadensis Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum
CentrosauriniRubeosaurus ovatus Styracosaurus albertensis Coronosaurus brinkmani Centrosaurus apertus Spinops sternbergorum
Rubeosaurus ovatus Styracosaurus albertensis
Rubeosaurus ovatus
Styracosaurus albertensis
Coronosaurus brinkmani Centrosaurus apertus Spinops sternbergorum
Coronosaurus brinkmani
Centrosaurus apertus Spinops sternbergorum
Centrosaurus apertus
Spinops sternbergorum
PachyrhinosauriniEiniosaurus procurvicornis Pachyrostra Achelousaurus horneri Pachyrhinosaurus canadensis Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum
Einiosaurus procurvicornis
PachyrostraAchelousaurus horneri Pachyrhinosaurus canadensis Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum
Achelousaurus horneri
Pachyrhinosaurus canadensis Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum
Pachyrhinosaurus canadensis
Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum
Pachyrhinosaurus lakustai
Pachyrhinosaurus perotorum

See also

External links

  • , by Julius T. Csotonyi
  • from the Calgary Sun