Ceratops
Encyclopedia
Ceratops is a dubious
genus
of ceratopsia
n dinosaur
which lived during the Late Cretaceous
. Its fossils have been found in Montana
. Although poorly known, Ceratops is important in the history of dinosaurs, since it is the type species
for which both Ceratopsia
and Ceratopsidae
are named. Unfortunately, the material is too poor to be confidently referred to better specimens, and Ceratops is considered a nomen dubium
.
condyle and a pair of horn cores) were found by John Bell Hatcher
(1861–1904) in the summer of 1888 in the uppermost Judith River Formation
of Montana. O. C. Marsh originally believed the animal to be similar to Stegosaurus
, but with two horns on its head.
In 1995, Trexler and Sweeney noted that complete material from a bonebed that had been found in Montana
could enable Ceratops to be reexamined. The site, known as the Mansfield Bonebed, belongs to the same stratigraphic level as the one the yielded the original Ceratops remains. It had initially been interpreted as containing Styracosaurus
, but what earlier authors considered the frill spikes of Styracosaurus turned out to be chasmosaurine orbital horns. Trexler and Sweeney pointed out that these horns closely resembled those of Ceratops, and could allow the genus to be rescued as a valid name. The ceratopsids in the bonebed were later referred to the genus Albertaceratops
, and later re-classified in their own genus, Medusaceratops
.
In 2005, remarkably well preserved cranial and post cranial elements of a Judithian
ceratopsian were discovered in Fergus County, Montana
. Examination suggests close affinity with C. montanus. The locality has been determined to be on or in close proximity to the stratigraphic layer of C. montanus, and not too many miles away. The fossils have since been meticulously prepared, studied and evaluated. A team of writers is currently (Q1, 2011) in the process of preparing for publication. This specimen may or may not be referred to C. montanus; debate on the merits of referring to a nomen dubium versus a new species designation continue.
for "horned face"), a group of herbivorous dinosaurs with parrot
-like beaks which thrived in North America
and Asia
during the Cretaceous Period, which ended roughly 65 million years ago.
In 1999, Penkalski and Dodson concluded Ceratops is a nomen dubium
because the material is too meager. They add that Avaceratops
appears closely related and may even be a juvenile Ceratops but there is not enough material to prove it.
Others:
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of ceratopsia
Ceratopsia
Ceratopsia or Ceratopia is a group of herbivorous, beaked dinosaurs which thrived in what are now North America, Europe, and Asia, during the Cretaceous Period, although ancestral forms lived earlier, in the Jurassic. The earliest known ceratopsian, Yinlong downsi, lived between 161.2 and 155.7...
n dinosaur
Dinosaur
Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...
which lived during the Late Cretaceous
Late Cretaceous
The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...
. Its fossils have been found in Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
. Although poorly known, Ceratops is important in the history of dinosaurs, since it is the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
for which both Ceratopsia
Ceratopsia
Ceratopsia or Ceratopia is a group of herbivorous, beaked dinosaurs which thrived in what are now North America, Europe, and Asia, during the Cretaceous Period, although ancestral forms lived earlier, in the Jurassic. The earliest known ceratopsian, Yinlong downsi, lived between 161.2 and 155.7...
and Ceratopsidae
Ceratopsidae
Ceratopsidae is a speciose group of marginocephalian dinosaurs including Triceratops and Styracosaurus...
are named. Unfortunately, the material is too poor to be confidently referred to better specimens, and Ceratops is considered a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
.
History
The first remains referred to Ceratops (an occipitalOccipital
The word occipital, in zoology, pertains to the occiput .Occipital is a descriptor for several areas of animal & human anatomy.*External occipital protuberance* Internal occipital crest* Greater occipital nerve...
condyle and a pair of horn cores) were found by John Bell Hatcher
John Bell Hatcher
John Bell Hatcher was an American paleontologist and fossil hunter best known for discovering Torosaurus.-Biography:...
(1861–1904) in the summer of 1888 in the uppermost Judith River Formation
Judith River Formation
The Judith River Formation is a fossil-bearing geologic formation in Montana, and is part of the Judith River Group. It dates to the upper Cretaceous, between 80 and 75 million years ago, corresponding to the "Judithian" land vertebrate age...
of Montana. O. C. Marsh originally believed the animal to be similar to Stegosaurus
Stegosaurus
Stegosaurus is a genus of armored stegosaurid dinosaur. They lived during the Late Jurassic period , some 155 to 150 million years ago in what is now western North America. In 2006, a specimen of Stegosaurus was announced from Portugal, showing that they were present in Europe as well...
, but with two horns on its head.
In 1995, Trexler and Sweeney noted that complete material from a bonebed that had been found in Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
could enable Ceratops to be reexamined. The site, known as the Mansfield Bonebed, belongs to the same stratigraphic level as the one the yielded the original Ceratops remains. It had initially been interpreted as containing Styracosaurus
Styracosaurus
Styracosaurus was a genus of herbivorous ceratopsian dinosaur from the Cretaceous Period , about 76.5 to 75.0 million years ago...
, but what earlier authors considered the frill spikes of Styracosaurus turned out to be chasmosaurine orbital horns. Trexler and Sweeney pointed out that these horns closely resembled those of Ceratops, and could allow the genus to be rescued as a valid name. The ceratopsids in the bonebed were later referred to the genus Albertaceratops
Albertaceratops
Albertaceratops was a genus of centrosaurine horned dinosaur from the middle Campanian-age Upper Cretaceous Oldman Formation of Alberta, Canada....
, and later re-classified in their own genus, Medusaceratops
Medusaceratops
Medusaceratops is a genus of herbivorous ceratopsian dinosaur. It is a chasmosaurine ceratopsian which lived during the Late Cretaceous period in what is now Montana. It is known from two partial parietals, the holotype WDC DJR 001 and the paratype WDC DJR 002...
.
In 2005, remarkably well preserved cranial and post cranial elements of a Judithian
Judith River Formation
The Judith River Formation is a fossil-bearing geologic formation in Montana, and is part of the Judith River Group. It dates to the upper Cretaceous, between 80 and 75 million years ago, corresponding to the "Judithian" land vertebrate age...
ceratopsian were discovered in Fergus County, Montana
Fergus County, Montana
-National protected areas:* Charles M. Russell National Wildlife Refuge * Lewis and Clark National Forest * Upper Missouri River Breaks National Monument -Demographics:...
. Examination suggests close affinity with C. montanus. The locality has been determined to be on or in close proximity to the stratigraphic layer of C. montanus, and not too many miles away. The fossils have since been meticulously prepared, studied and evaluated. A team of writers is currently (Q1, 2011) in the process of preparing for publication. This specimen may or may not be referred to C. montanus; debate on the merits of referring to a nomen dubium versus a new species designation continue.
Classification
Ceratops belonged to the Ceratopsia (the name is Ancient GreekAncient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
for "horned face"), a group of herbivorous dinosaurs with parrot
Parrot
Parrots, also known as psittacines , are birds of the roughly 372 species in 86 genera that make up the order Psittaciformes, found in most tropical and subtropical regions. The order is subdivided into three families: the Psittacidae , the Cacatuidae and the Strigopidae...
-like beaks which thrived in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
during the Cretaceous Period, which ended roughly 65 million years ago.
In 1999, Penkalski and Dodson concluded Ceratops is a nomen dubium
Nomen dubium
In zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
because the material is too meager. They add that Avaceratops
Avaceratops
Avaceratops is a genus of small ceratopsian dinosaur which lived during the late Campanian during the Late Cretaceous Period in what are now the Northwest United States.-Discoveries and species:...
appears closely related and may even be a juvenile Ceratops but there is not enough material to prove it.
Species
Type:- Ceratops montanus Marsh 1888 (USNM 2411)
Others:
- C. (Bison) alticornis (Marsh 1887/1889). This was the famous pair of horn cores that were originally thought by Marsh to be from a giant bisonBisonMembers of the genus Bison are large, even-toed ungulates within the subfamily Bovinae. Two extant and four extinct species are recognized...
. Marsh realized his error in 1889 and referred the horns to his Ceratops. Today they are recognized as the first TriceratopsTriceratopsTriceratops is a genus of herbivorous ceratopsid dinosaur which lived during the late Maastrichtian stage of the Late Cretaceous Period, around 68 to 65 million years ago in what is now North America. It was one of the last dinosaur genera to appear before the great Cretaceous–Paleogene...
remains found and are, to date, the southernmost known Triceratops fossils. Even as Triceratops, it also is a nomen dubiumNomen dubiumIn zoological nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application...
. - C. (ChasmosaurusChasmosaurusChasmosaurus is a genus of ceratopsid dinosaur from the Upper Cretaceous Period of North America. Its name means 'opening lizard', referring to the large openings in its frill . With a length of and a weight of , Chasmosaurus was a ceratopsian of average size...
) belli (Lambe 1902/Hatcher vide Stanton & Hatcher 1905) - C. (Eoceratops) canadensis (Lambe 1902/Hatcher vide Stanton & Hatcher 1905)
- C. (Triceratops) horridus (Marsh 1889). This was the first intact ceratopsian skull discovered and led Marsh to realize the significance of the other specimens. As with the aforementioned species, it too is currently recognized as Triceratops.
- C. paucidens (Marsh 1889/1890); nomem dubium included with LambeosaurusLambeosaurusLambeosaurus is a genus of hadrosaurid dinosaur that lived about 76 to 75 million years ago, in the Late Cretaceous Period of North America. This bipedal/quadrupedal, herbivorous dinosaur is known for its distinctive hollow cranial crest, which in the best-known species resembled a hatchet...
lambei - C. (Chasmosaurus) recurvicornis (Cope 1890/Hatcher vide Stanton & Hatcher 1905)
External links
- http://www.dinosaurvalley.com/Visiting_Drumheller/Kids_Zone/Groups_of_Dinosaurs/index.php