After Ryan & Russell, 2005, and Ryan, 2007
<==o †Ceratopsidae Marsh, 1890a [Ceratopidae Marsh, 1890 emend. ??, Agathaumidae Cope] |--o †Centrosaurinae Lambe, 1915 [Pachyrhinosaurinae] | |?- †Avaceratops lammersi Dobson, 1986 | |?- †Brachyceratops montanensis Gilmore, 1914b (nomen dubium?) | |?- †Monoclonius crassus Cope, 1876a (nomen dubium?) | |-- †Albertaceratops nesmoi Ryan, 2006 | `--+--o †Centrosaurus Lambe, 1904b [Monocolonius Lambe, 1902; Centrosaurssus Ryan & Russell, 2005 (lapsus calami)] | | |-- †C. apertus Lambe, 1904b [incl. Monoclonius dawsoni Lambe, 1902; C. flexus Brown, 1914; M. cutleri, M. nasicornis Brown, 1917; M. longirostris Sternberg, 1940] | | `-- †C. brinkmani Ryan & A.P. Russell, 2005 | `--+--o †Styracosaurus Lambe, 1913 | | |-- †S. albertensis Lambe, 1913 [?Monoclonius nasicornus Brown, ] | | `-- †S. ovatus Gilmore, 1930 | `--o †Pachyrhinosaurini sensu Sampson, 1995b | |-- †Einiosaurus procurvicornis Sampson, 1995b | `--+-- †Achelousaurus horneri Sampson, 1995b | `--o †Pachyrhinosaurus Sternberg, 1950 | |-- †P. sp. [Wapiti formation, North America] | `-- †P. canadiensis Sternberg, 1950 `--o Chasmosaurinae Lambe, 1915 [Ceratopinae Marsh, 1890a, Ceratopsinae Marsh, 1890a emend. ??, Eoceratopsinae] |?- †Ceratops hatcheri [C. montanus?] [nomen dubium??] |?- †Eotriceratops xerinsularis Wu, Brinkman, Eberth & Braman, 2007 |--o †Triceratops Marsh, 1889b sensu Forster, 1996 [taxonomic history] | |?- †T. prorsus Marsh, 1890 [taxonomic history] | `-- †T. horridus Marsh, 1889a [taxonomic history] `--+--o †Torosaurus Marsh, 1891b [taxonomic history] | |-- †T. latus Marsh, 1891b [taxonomic history] | `-- †T. utahensis (Gilmore, 1946b) [taxonomic history] `--+--+-- †Arrhinoceratops brachyops Parks, 1925 | `--o †Anchiceratops Lambe, 1914a | |-- †A. ornatus Lambe, 1914a | `-- †A. sp. [Judith River Formation, North America] `--+-- †Pentaceratops sternbergii Osborn, 1923b `--+?- †Agujaceratops mariscalensis (Lehman, 1989) Lucas, Sullivan & Hunt, 2006 [†Chasmosaurus mariscalensis Lehman, 1989] `--o †Chasmosaurus Lambe, 1914a [Monoclonius] |?- †C. canadiensis (Lambe, 1902) [Monoclonius canadiensis Lambe, 1902] |-- †C. russelli Sternberg, 1940b `--+-- †C. irvinensis Holmes, Forster, Ryan & Shepherd, 2001 `-- †C. belli (Lambe, 1914a) [Monoclonius belli Lambe, 1902]
Reference(s):
- Dodson, P., 1996: The Horned Dinosaurs.
–Princeton University Press, Pinceton, New Jersey, pp. xiv-346 - Dodson, P., & Currie, P. J., 1990: Neoceratopsia. 593-618.
in Weishampel, D. B., Dodson, P., & Osmólska, H. (eds.), 1990: The Dinosauria.
–University of California Press, Berkley, Los Angeles, Oxford, 1990 xvi-733 - Forster, C. A., 1996: Species resolution in Triceratops: Cladistic and morphometric approaches.
–Journal of Vertebrate Paleontology: Vol. 16, #2, pp. 259-270 - Godfrey, S. J. & Holmes, R., 1995: Cranial morphology and systematics of Chasmosaurus (Dinosauria: Ceratopsidae) from the Upper Cretaceous of Western Canada.
–Journal of Vertebrate Paleontology: Vol. 15, #4, pp. 726-742 - Holmes, R. B., Forster, C. A., Ryan, M. J. & Shepherd, K. M., 2001: A new species of Chasmosaurus (Dinosauria: Ceratopsia) from the Dinosaur Park Formation of southern Alberta.
–Canadian Journal of Earth Sciencies: Vol. 38, #12, pp. 1423-1438 - Keesey, T. M., 1996-2000: The Dinosauricon
–iNet: The Dinosauricon: http://dinosauricon.com/ - Lehman, T. M., 1989: Chasmosaurus mariscalensis, sp. nov., a new ceratopsian dinosaur from Texas.
–Journal of Vertebrate Paleontology: Vol. 9, #2, pp. 137-162 - Ryan, M. J., 2007: A new basal centrosaurine ceratopsid from the Oldman Formation, southeastern Alberta.
–Journal of Paleontology: Vol. 81, #2, pp. 376-396 [doi: 0022-3360/07/0081-376] - Ryan, M. J. & Russell, A. P., 2005: A new centrosaurine ceratopsid from the Oldman Formation of Alberta and its implications for centrosaurine taxonomy and systematics.
–Canadian Journal of Earth Sciencies: Vol. 42, #7, pp. 1369-1387 - Sampson, S. D., 1995: Two new horned dinosaurs from the Upper Cretaceous Two Medicine Formation of Montana; with a phylogenetic analysis of the Centrosaurinae (Ornithischia: Ceratopsidae).
–Journal of Vertebrate Paleontology: Vol. 15, #4, pp. 743-760 - Sullivan, R. M., Boere, A. C. & Lucas, S. G., 2005: Redescription of the ceratopsid dinosaur Torosaurus utahensis (Gilmore, 1946) an a revision of the genus.
–Journal of Paleontology: Vol. 79, #3, pp. 564-582 - Wu, X.-C., Brinkman, D. B., Eberth, D. A. & Braman, D. R., 2007: A new ceratopsid dinosaur (Ornithischia) from the uppermost Horseshoe Canyon Formation (upper Maastrichtian), Alberta, Canada.
–Canadian Journal of Earth Sciencies: Vol. 44, #9, pp. 1243-1265 [doi: 10.1139/E07-011]