Chasmosaurinae

Chasmosaurinae
	Skeletal reconstruction of Pentaceratops sternbergii
Temporal occurrence
	Upper Cretaceous (middle Campanium to Maastrichtian )
	80.6 to 66 million years
Locations
	western North America ( Laramidia );
Systematics
	Cerapoda
	Marginocephalia
	Ceratopsia
	Neoceratopsia
	Ceratopsidae
	Chasmosaurinae
Scientific name
	Chasmosaurinae
	Lambe , 1915

The Chasmosaurinae (also Ceratop (s) inae ) are a taxon (a systematic group) of the dinosaurs . Together with the Centrosaurinae they form the group of the Ceratopsidae within the Ceratopsia .

features

Typical of the Chasmosaurinae (here Anchiceratops ) were the short nasal horn, the long over-eye horns and the elongated neck shield.

The Chasmosaurinae moved like all Ceratopsidae quadruped (four-legged), whereby the front legs were clearly shorter than the hind legs. The extremities were generally strong, the body stocky.

The skull was large and massive and had a pointed muzzle. As with all Ceratopsia, this was formed from the rostral bone (in front of the upper jaw) and the predentals (in front of the lower jaw). As with all Ceratopsidae , the dentition consisted of tooth batteries , these are teeth arranged in rows, which were replaced by the next tooth after they were worn out.

The most noticeable differences to the Centrosaurinae were in the horns and the neck shield. The nasal horn was greatly shortened, in return, the over-eye horns were significantly elongated. The neck shield, which, like all higher Ceratopsia, was formed from the parietal and scaled bones , was mostly long - sometimes up to 100 percent of the actual skull length - and had large openings - only in Triceratops it was shortened and closed.

The length of the skull including the neck shield reached over two meters in Pentaceratops and Torosaurus , which are the longest known skulls of all land-dwelling animals. The bony structures on the edge of the shield ( Epoccipitalia ) were at best simple knobs and not spines as in some Centrosaurinae.

Distribution and systematics

Relationships of the Chasmosaurinae according to Sampson et al. (2010)

Triceratops

As with all Ceratopsidae, the fossil evidence of the Chasmosaurinae can only be found in the western part of North America. The west of the continent was an island known as Laramidia during most of the Cretaceous . This paleo-island was isolated by a shallow sea, the Western Interior Seaway , so the ceratopsids were restricted to Laramidia, so they were endemic there . Fossil remains of this group of dinosaurs are only known from the Upper Cretaceous (middle Campanian to Maastrichtian ) and are therefore around 80 to 66 million years old.

The following genera are assigned to the Chasmosaurinae:

Since the material from Ceratops , after which the Ceratopsidae are named, is too poor for a precise systematic determination, Lawrence Lambe named this group after Chasmosaurus in 1915 . The membership of Triceratops in this group was only recognized later, as this dinosaur with its short neck shield differs significantly from the other members.

literature

Peter Dodson , Catherine A. Forster, Scott D. Sampson: Ceratopsidae. In: David B. Weishampel , Peter Dodson, Halszka Osmólska (eds.): The Dinosauria . 2nd edition. University of California Press, Berkeley CA et al. 2004, ISBN 0-520-24209-2 , pp. 494-513.
David E. Fastovsky , David B. Weishampel: The Evolution and Extinction of the Dinosaurs. 2nd edition. Cambridge University Press, Cambridge et al. 2005, ISBN 0-521-81172-4 .

Individual evidence

↑ ^a ^b ^c ^d ^e Scott D. Sampson, Mark A. Loewen, Andrew A. Farke, Eric M. Roberts, Catherine A. Forster, Joshua A. Smith, Alan L. Titus: New Horned Dinosaurs from Utah Provide Evidence for Intracontinental Dinosaur Endemism. In: PLoS ONE . Vol. 5, No. 9, 2010, e12292, doi : 10.1371 / journal.pone.0012292 .

^ Gregory S. Paul : The Princeton Field Guide To Dinosaurs. Princeton University Press, Princeton NJ et al. 2010, ISBN 978-0-691-13720-9 , pp. 265–272, Online ( Memento of the original from July 13, 2015 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. . @1@ 2

↑ Michael J. Ryan, Anthony P. Russell, Scott Hartman: A New Chasmosaurine Ceratopsid from the Judith River Formation, Montana. In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, David A. Eberth: New Perspectives on Horned Dinosaurs. The Royal Tyrrell Museum Ceratopsian Symposium. Indiana University Press, Bloomington IN et al. 2010, ISBN 978-0-253-35358-0 , pp. 181-188.

↑ Michael J. Ryan, David C. Evans, Philip J. Currie , Mark A. Loewen: A new chasmosaurine from northern Laramidia expands frill disparity in ceratopsid dinosaurs. In: Natural Sciences . Vol. 101, No. 6, 2014, pp. 505-512, doi : 10.1007 / s00114-014-1183-1 .

^ Nicholas R. Longrich: A New Chasmosaurine Ceratopsid from the Late Campanian of Western Canada. In: Journal of Paleontology. Vol. 84, No. 4, 2010, ISSN 0022-3360 , pp. 681-694, doi : 10.1666 / 09-114.1 .

^ Robert M. Sullivan, Spencer G. Lucas: A New Chasmosaurine (Ceratopsidae, Dinosauria) from the Upper Cretaceous Ojo Alamo Formation (Naashoibito Member), San Juan Basin, New Mexico. In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, David A. Eberth: New Perspectives on Horned Dinosaurs. The Royal Tyrrell Museum Ceratopsian Symposium. Indiana University Press, Bloomington IN et al. 2010, ISBN 978-0-253-35358-0 , pp. 169-180.

↑ Brown et al. A New Horned Dinosaur Reveals Convergent Evolution in Cranial Ornamentation in Ceratopsidae . Current Biology, 2015 DOI: 10.1016 / j.cub.2015.04.041

↑ Jordan C. Mallon, Christopher J. Ott, Peter L. Larson, Edward M. Iuliano and David C. Evans (2016). Spiclypeus shipporum gen. Et sp. nov., a Boldly Audacious New Chasmosaurine Ceratopsid (Dinosauria: Ornithischia) from the Judith River Formation (Upper Cretaceous: Campanian) of Montana, USA . PLoS ONE 11 (5): doi: 10.1371 / journal.pone.0154218

↑ Christopher J. Ott, Peter L. Larson: A New, Small Ceratopsian Dinosaur from the Latest Cretaceous Hell Creek Formation, Northwest South Dakota, United States: A Preliminary Description. In: Michael J. Ryan, Brenda J. Chinnery-Allgeier, David A. Eberth: New Perspectives on Horned Dinosaurs. The Royal Tyrrell Museum Ceratopsian Symposium. Indiana University Press, Bloomington IN et al. 2010, ISBN 978-0-253-35358-0 , pp. 203-218.

↑ Nicholas R. Longrich: Titanoceratops ouranos, a giant horned dinosaur from the late Campanian of New Mexico. In: Cretaceous Research. Vol. 32, No. 3, 2010, ISSN 0195-6671 , pp. 264-276, doi : 10.1016 / j.cretres.2010.12.007 .

Web links

Commons : Chasmosaurinae - collection of images, videos and audio files

[Sampson-1] Scott D. Sampson, Mark A. Loewen, Andrew A. Farke, Eric M. Roberts, Catherine A. Forster, Joshua A. Smith, Alan L. Titus: New Horned Dinosaurs from Utah Provide Evidence for Intracontinental Dinosaur Endemism. In: PLoS ONE . Vol. 5, No. 9, 2010, e12292, doi : 10.1371 / journal.pone.0012292 .