Name:
Chasmosaurus
(Cleft lizard).
Phonetic: Kazz-moe-sore-us.
Named By: Lawrence Lambe - 1914.
Synonyms: Eoceratops, Mojoceratops.
Classification: Chordata, Reptilia, Dinosauria,
Ornithischia, Ceratopsia, Ceratopsidae, Chasmosaurinae.
Species: C. belli (type), C.
russelli.
Type: Herbivore.
Size: 4.3 to 4.8 meters long.
Known locations: Canada, Alberta - Dinosaur Park
Formation.
Time period: Campanian of the Cretaceous.
Fossil representation: Many specimens are known
allowing for accurate reconstruction. Fossilised skin is also known.
The
elongated frill of Chasmosaurus had two large
fenestra in the middle
which would have had a skin covering in life giving the appearance of a
'solid' frill. As a display device the frill may have been brightly
coloured with an elaborate display. Also since the frill in these parts
was soft tissue, Chasmosaurus may have flushed
blood into the area to
make the colours even more vivid. The flushing of blood has also
brought forth ideas of a possible heat exchange device for
thermoregulation, with blood flushed into the area to allow it to cool
across a larger surface area. However, because the large fenestrae were
filled only with skin, the frill would have provided only minimal
defence against a predator.
Chasmosaurus
has also been used as the base for the name of the ceratopsian
group
Chasmosaurinae. The ceratopsian dinosaurs of this
group are noted for
their large, long neck frills and relatively short horns, and include
others such as Pentaceratops
and Anchiceratops.
Further reading
- New genera and species from the Belly River Series (mid-Cretaceous) -
Geological Survey of Canada Contributions to Canadian Palaeontology
3(2): 25-81 - L. M. Lambe - 1902.
- On Gryposaurus notabilis, a new genus and species
of trachodont
dinosaur from the Belly River Formation of Alberta, with a description
of the skull of Chasmosaurus belli - The Ottawa
Naturalist 27: 145-155
- L. M. lambe - 1914.
- Integument of Chasmosaurus belli - Canadian
Field-Naturalist 39:
108-110 - C. M. Sternberg - 1925.
- Ceratopsidae from Alberta - Journal of Paleontology 14(5):468-480 -
C. M. Sternberg - 1940.
- Chasmosaurus mariscalensis, sp. nov., a new
ceratopsian dinosaur from
Texas - Journal of Vertebrate Paleontology, 9(2): 137-162 - T. M.
Lehman - 1989.
- The ceratopsian subfamily Chasmosaurinae: sexual dimorphism and
systematics - T. M. Lehman - 1990 - In Dinosaur Systematics:
Perspectives and Approaches, Cambridge University Press, Cambridge, pp.
211-229 - K. Carpenter & P. J. Currie (eds.).
- Chasmosaurus mariscalensis skull from Big Bend
National Park - C. A.
Forster & P. C. Sereno - 1993 - In National Park Service
Paleontology Research Abstract Volume. Technical Report NPS/NRPEFO/NRTR
93/11:14 - V. Santucci (ed.).
- Cranial morphology and systematics of Chasmosaurus
(Dinosauria:
Ceratopsidae) from the Upper Cretaceous of western Canada - Journal of
Vertebrate Paleontology 15(4):726-742 - S. J. Godfrey & R.
Holmes - 1995.
- A new species of Chasmosaurus (Dinosauria:
Ceratopsia) from the
Dinosaur Park Formation of southern Alberta - Canadian Journal of Earth
Sciences 38: 1423–1438 - R. B. Holmes, C. A. Forster, M. J. Ryan
& K. M. Shepherd - 2001.
- Re-evaluation of Pentaceratops and Chasmosaurus
(Ornithischia:
Ceratopsidae) in the Upper Cretaceous of the Western Interior - S. G.
Lucas, R. M. Sullivan & A. P. Hunt - 2006 - In Late Cretaceous
Vertebrates from the Western Interior. New Mexico Museum of Natural
History and Science Bulletin 35:367-370 - S. G. Lucas and R. M.
Sullivan (eds.).
- Mojoceratops perifania, A New Chasmosaurine
Ceratopsid from the Late
Campanian of Western Canada. - Journal of Paleontology 84 (4): 681–694.
- Nicholas R. Longrich - 2010.
- A new specimen of Chasmosaurus belli
(Ornithischia: Ceratopsidae), a
revision of the genus, and the utility of postcrania in the taxonomy
and systematics of ceratopsid dinosaur - Zootaxa, 2963: 1-47 - S. C. R.
Maidment & P. M. Barrett - 2011.
- A Re-Evaluation of the chasmosaurine ceratopsid genus Chasmosaurus
(Dinosauria: Ornithischia) from the Upper Cretaceous (Campanian)
Dinosaur Park Formation of Western Canada. - PLoS ONE, 11(1): e0145805.
- J. A. Campbell, M. J. Ryan, R. B. Holmes & C. J.
Schr�der-Adams - 2016.