Pentaceratops

Taxobox
name = "Pentaceratops"
fossil_range = Late Cretaceous

---

image_width = 250px
| regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Ornithischia
subordo = Ceratopsia
familia = Ceratopsidae
subfamilia = Ceratopsinae
genus = "Pentaceratops"
genus_authority = Osborn, 1923
subdivision_ranks = Species
subdivision=
* "P. sternbergii" (type) Osborn, 1923

"Pentaceratops" is a genus of ceratopsid dinosaur from the late Cretaceous Period of what is now North America. Its name means "five-horned face", derived from the Greek "penta/πέντα"" meaning 'five', "ceras/κέρας"" meaning 'horn' and "-ops/ωψ"" meaning 'face' [ cite book|author=Liddell & Scott|year=1980|title=Greek-English Lexicon, Abridged Edition |publisher=Oxford University Press, Oxford, UK|id=ISBN 0-19-910207-4] , in reference to its two long epijugal bones, spikes which protrude out sidewards from under its eyes, in addition to the three more obvious horns.

"Pentaceratops" lived around 75-73 million years ago, its remains having been mostly found in the Kirtland Formation [ Sullivan, R.M. and S.G. Lucas. 2006. The Kirtlandian land-vertebrate “age”— faunal composition, temporal position and biostratigraphic correlation in the nonmarine Upper Cretaceous of western North America. New Mexico Museum of Natural History and Science Bulletin 35:7-29] in the San Juan Basin in New Mexico. Other dinosaurs which shared its time period include "Parasaurolophus cyrtocristatus", the pachycephalosaur "Prenocephale", the armored dinosaur "Nodocephalosaurus" and possibly the tyrannosaurid "Daspletosaurus".

It was about 8 m (27 ft) long, and has been estimated to have weighed around 5,500 kg (13,000 lb).

Discoveries and species

The first examples were collected by C. H. Sternberg in the San Juan Basin in New Mexico and described by Henry Fairfield Osborn in 1923, who obligingly gave it the specific name "sternbergii" after its discoverer. The frill of "Pentaceratops" is larger than that of "Triceratops", with two large holes (fenestrae) in it. In 1930, Carl Wiman described a second species of "Pentaceratops", "P. fenestratus", but this was later determined to be the same species as the original finds. Further material discovered in Colorado has been identified as "Pentaceratops" in 2006. [Lucas, S.G., Sullivan, R.M., Hunt, A.P., 2006c, Re-evaluation of "Pentaceratops" and "Chasmosaurus" (Ornithischia, Ceratopsidae) in the Upper Cretaceous of the Western Interior: New Mexico Museum of Natural History and Science, Bulletin 35]

"Pentaceratops" species
*"P. sternbergii"

"Pentaceratops" has the distinction of having produced the largest known skull for a land vertebrate. That skull and its associated skeleton are on display at the Sam Noble Oklahoma Museum of Natural History [http://www.sciencemag.org/cgi/content/summary/282/5390/871b?rbfvrToken=c79498a2bee3849d539afdf3f2fc9e7394445b48] . The skeleton was found in New Mexico in 1941.

Classification

Within the Ceratopsia, "Pentaceratops" belonged to the subfamily Ceratopsinae and appears to be most closely related to "Anchiceratops" and the earlier genus "Chasmosaurus". It may have been a close relative to the ancestor of "Torosaurus", which lived a few million years later, right at the end of the Cretaceous period, when all ceratopsians died out.

Diet

"Pentaceratops", like all ceratopsians, was an herbivore. During the Cretaceous, flowering plants were "geographically limited on the landscape", and so it is likely that this dinosaur fed on the predominant plants of the era: ferns, cycads and conifers. It would have used its sharp ceratopsian beak to bite off the leaves or needles.

References

*cite book|author=Dodson, P.|year=1996|title=The Horned Dinosaurs|publisher=Princeton University Press, Princeton, New Jersey|id=ISBN 0-691-05900-4

External links

* [http://www.dinodata.org/index.php?option=com_content&task=view&id=7236&Itemid=67 "Pentaceratops" at DinoData]
* [http://www.isgs.uiuc.edu/dinos/de_4/5a795a0.htm "Pentaceratops", from the Dinosaur Encyclopaedia] at Dino Russ' Lair
* [http://www.dinosaurvalley.com/Visiting_Drumheller/Kids_Zone/Groups_of_Dinosaurs/index.php Kids Zone page on dinosaur types]
* [http://dino.lm.com/images/display.php?id=619 Photo of Pentaceratops skull at Sam Noble Museum]