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Vagaceratops Temporal range: Late Cretaceous, | |
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Cast of the holotype skull, Canadian Museum of Nature | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Ceratopsia |
Family: | † Ceratopsidae |
Subfamily: | † Chasmosaurinae |
Genus: | † Vagaceratops Sampson et al., 2010 |
Species: | †V. irvinensis |
Binomial name | |
†Vagaceratops irvinensis (Holmes et al., 2001 [originally Chasmosaurus ]) | |
Synonyms | |
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Vagaceratops (meaning "wandering (vagus, Latin) horned face", in reference to its close relationship with Kosmoceratops from Utah) is a genus of herbivorous ceratopsian dinosaur. It is a chasmosaurine ceratopsian which lived during the Late Cretaceous period (late Campanian) in what is now Alberta. Its fossils have been recovered from the Upper Dinosaur Park Formation. It is sometimes included in the genus Chasmosaurus as Chasmosaurus irvinensis instead of being recognized as its own genus.
In 2010, paleontologist Scott D. Sampson and colleagues named Vagaceratops (from the Dinosaur Park Formation, whose sole species, C. irvinensis, was formerly placed in Chasmosaurus ), as well as Kosmoceratops and Utahceratops (from the Kaiparowits Formation) in the same article. [1] These genera, which were considered unusual compared to typical members of their group, were part of a spate of ceratopsian discoveries in the early 21st century, when many new taxa were named (a 2013 study stated that half of all valid genera were named since 2003, and the decade has been called a "ceratopsid renaissance"). [2] [3] [4]
Vagaceratops was a medium-sized ceratopsian, reaching 4.5 m (15 ft) in length and weighing 1.2 t (1.3 short tons). [5] It is known primarily from three fossil skulls. Although the general structure was typical of ceratopsids (i.e. a parrot-like beak, large neck frill, and nasal horn) it has some peculiarities. The skulls are characterized by a reduced supraorbital horn, brow horns that are reduced to low bosses and a larger snout compared to related animals. Vagaceratops had smaller parietal fenestrae than most ceratopsids and had a strange configuration of epoccipitals (bones surrounding the frill). It possessed ten epoccipitals, eight of which were centrally flattened, curved forward and upward and fused together to form a jagged margin along the back of the frill. The frill was shorter and more square-shaped than other chasmosaurines, being wider than it was long.
Vagaceratops was named by Scott D. Sampson, Mark A. Loewen, Andrew A. Farke, Eric M. Roberts, Catherine A. Forster, Joshua A. Smith, and Alan L. Titus in 2010, and the type species is Vagaceratops irvinensis. [1] This species was originally described as a species of Chasmosaurus (C. irvinensis) in 2001. [6] Its relationships remain debated. Vagaceratops has variously been allied with Kosmoceratops [1] or with Chasmosaurus. [7] [6]
The cladogram below is the phylogeny of the Chasmosaurinae by Brown et al. (2015): [8]
Ceratopsidae |
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Recently it has been suggested that Chasmosaurinae had a deep evolutionary split between a Chasmosaurus clade and a Pentaceratops clade. Vagaceratops was hypothesized to be the last member of the Chasmosaurus clade from northern Laramidia, with the last representative of the clade being its close relative Kosmoceratops. [9]
Torosaurus is a genus of herbivorous chasmosaurine ceratopsian dinosaur that lived during the late Maastrichtian age of the Late Cretaceous period, between 68 and 66 million years ago, though it is possible that the species range might extend to as far back as 69 million years ago. Fossils have been discovered across the Western Interior of North America, from as far north as Saskatchewan to as far south as Texas.
Chasmosaurus is a genus of ceratopsid dinosaur from the Late Cretaceous Period in North America. Its given name means 'opening lizard', referring to the large openings (fenestrae) in its frill. With a length of 4.3–4.8 metres (14.1–15.7 ft) and a weight of 1.5–2 tonnes —or anywhere from 2,200 to nearly 5,000 lbs., give or take—Chasmosaurus was of a slightly smaller to ‘average’ size, especially when compared to larger ceratopsians. The Chasmosaurs were similar, in overall build and weight, to a white rhinoceros or an Indian rhinoceros; just like rhinos, and all other ceratopsians, they were purely herbivorous, needing to consume around 54 kilograms, or 120 lbs., of plant matter each day.
Ceratopsia or Ceratopia is a group of herbivorous, beaked dinosaurs that 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 million years ago. The last ceratopsian species, Triceratops prorsus, became extinct during the Cretaceous–Paleogene extinction event, 66 million years ago.
Pentaceratops is a genus of herbivorous ceratopsid dinosaur from the late Cretaceous Period of what is now North America. Fossils of this animal were first discovered in 1921, but the genus was named in 1923 when its type species, Pentaceratops sternbergii, was described. Pentaceratops lived around 76–73 million years ago, its remains having been mostly found in the Kirtland Formation in the San Juan Basin in New Mexico. About a dozen skulls and skeletons have been uncovered, so anatomical understanding of Pentaceratops is fairly complete. One exceptionally large specimen later became its own genus, Titanoceratops, due to its more derived morphology, similarities to Triceratops, and lack of unique characteristics shared with Pentaceratops.
Nedoceratops is a controversial genus of ceratopsid dinosaur from the Late Cretaceous period Lance Formation of North America. It is known only from a single skull discovered in Wyoming. Its status is the subject of ongoing debate among paleontologists: some authors consider Nedoceratops a valid, distinct taxon, while others consider it to be an unusual specimen of Triceratops.
Anchiceratops is an extinct genus of chasmosaurine ceratopsid dinosaur that lived approximately 72 to 71 million years ago during the latter part of the Cretaceous Period in what is now Alberta, Canada. Anchiceratops was a medium-sized, heavily built, ground-dwelling, quadrupedal herbivore that could grow up to an estimated 4.3 metres (14 ft) long. Its skull featured two long brow horns and a short horn on the nose. The skull frill was elongated and rectangular, its edges adorned by coarse triangular projections. About a dozen skulls of the genus have been found.
Arrhinoceratops is a genus of herbivorous ceratopsian dinosaur. The name was coined as its original describer concluded it was special because the nose-horn was not a separate bone, however further analysis revealed this was based on a misunderstanding. It lived during the latest Campanian/earliest Maastrichtian stage of the Late Cretaceous, predating its famous relative Triceratops by a few million years, although it was contemporary with Anchiceratops. Its remains have been found in Canada.
Medusaceratops is an extinct genus of centrosaurine ceratopsian dinosaur known from the Late Cretaceous Judith River Formation of Montana, northern United States. It contains a single species, Medusaceratops lokii.
Chasmosaurinae is a subfamily of ceratopsid dinosaurs. They were one of the most successful groups of herbivores of their time. Chasmosaurines appeared in the early Campanian, and became extinct, along with all other non-avian dinosaurs, during the Cretaceous–Paleogene extinction event. Broadly, the most distinguishing features of chasmosaurines are prominent brow horns and long frills lacking long spines; centrosaurines generally had short brow horns and relatively shorter frills, and often had long spines projecting from their frills.
Centrosaurinae is a subfamily of ceratopsid, a group of large quadrupedal ornithischian dinosaur. Centrosaurine fossil remains are known primarily from the northern region of Laramidia but isolated taxa have been found in China and Utah as well.
Coahuilaceratops is a genus of ceratopsian dinosaur. It is a chasmosaurine ceratopsian which lived during the Late Cretaceous period in what is now southern Coahuila in northern Mexico. It is known from the holotype CPC 276, a partial skeleton of an adult individual which includes several skull elements. Another specimen, CPS 277, may represent a juvenile Coahuilaceratops. All specimens of Coahuilaceratops were collected from a single location in the middle strata of the Cerro del Pueblo Formation, which dates to between 72.5 and 71.4 million years ago.
Utahceratops is an extinct genus of ceratopsian dinosaur that lived approximately 76.4~75.5 million years ago during the Late Cretaceous period in what is now Utah. Utahceratops was a large-sized, robustly-built, ground-dwelling, quadrupedal herbivore, that could grow up to an estimated 4.5–5 m (15–16 ft) long.
Kosmoceratops is a genus of ceratopsid dinosaur that lived in North America about 76–75.9 million years ago during the Late Cretaceous period. Specimens were discovered in Utah in the Kaiparowits Formation of the Grand Staircase–Escalante National Monument in 2006 and 2007, including an adult skull and postcranial skeleton and partial subadults. In 2010, the adult was made the holotype of the new genus and species Kosmoceratops richardsoni; the generic name means "ornate horned face", and the specific name honors Scott Richardson, who found the specimens. The find was part of a spate of ceratopsian discoveries in the early 21st century, and Kosmoceratops was considered significant due to its elaborate skull ornamentation.
Triceratopsini is a tribe of herbivorous chasmosaurine dinosaurs that lived between the late Campanian to the late Maastrichtian stages of the Cretaceous period, between 74.73 and 66 million years ago. Fossils of these animals have been found in western North America, in particular West Canada, Western and Midwestern United States, which was once part of the ancient continent of Laramidia. The tribe was named by Nicholas R. Longrich in 2011 for the description of Titanoceratops, which he defined as "all species closer to Triceratops horridus than to Anchiceratops ornatus or Arrhinoceratops brachyops". Triceratopsins were the largest of the chasmosaurines; suggesting that gigantism had evolved in the Ceratopsidae once. In addition there is an evolutionary trend in the solidification of the frills, the most extreme being in Triceratops.
Nasutoceratops is genus of ceratopsid dinosaur that lived in North America during the Late Cretaceous period, about 76.0–75.5 million years ago. The first known specimens were discovered in Utah in the Kaiparowits Formation of the Grand Staircase–Escalante National Monument (GSENM) from 2006 onwards, including a subadult skull with a partial postcranial skeleton and rare skin impressions and two partial skulls. In 2013, the subadult was made the holotype of the new genus and species Nasutoceratops titusi; the generic name means "large-nosed horned face", and the specific name honors the paleotologist Alan L. Titus for his work at the GSENM. The dinosaur was noted for its large nose in news reports, and later featured in Jurassic World films.
Coronosaurus is a genus of centrosaurine ceratopsian dinosaurs which lived in the Late Cretaceous, in the middle Campanian stage. Its remains, two bone beds, were discovered by Phillip J. Currie in the Oldman Formation of Alberta, Canada, and its type and only species, Coronosaurus brinkmani, was first described in 2005, as a new species within the genus Centrosaurus. Later studies questioned the presence of a direct relationship, and in 2012 it was named as a separate genus. Coronosaurus means "crowned lizard", coming from "corona", Latin for crown, and "sauros", Greek for lizard; this name refers to the unique, crown-like shape of the horns on the top of its frill.
Judiceratops is an extinct horned dinosaur. It lived around 78 million years ago, during the Late Cretaceous Period in what is now Montana, United States. Like other horned dinosaurs, Judiceratops was a large, quadrupedal herbivore. It is the oldest known chasmosaurine.
Bravoceratops is a genus of large chasmosaurine ceratopsid dinosaur that lived approximately 70 million years ago, and is known from the Late Cretaceous Javelina Formation in what is now Texas, United States.
This timeline of ceratopsian research is a chronological listing of events in the history of paleontology focused on the ceratopsians, a group of herbivorous marginocephalian dinosaurs that evolved parrot-like beaks, bony frills, and, later, spectacular horns. The first scientifically documented ceratopsian fossils were described by Edward Drinker Cope starting in the 1870s; however, the remains were poorly preserved and their true nature was not recognized. Over the next several decades, Cope named several such genera and species. Cope's hated rival, Othniel Charles Marsh, also described ceratopsian remains. In 1887, Marsh mistook a Triceratops horn for one belonging to a new species of prehistoric Bison. Marsh also named the eponymous genus Ceratops in 1888. The next year, he named the most famous ceratopsian, Triceratops horridus. It was the discovery of Triceratops that illuminated the ceratopsian body plan, and he formally named the Ceratopsia in 1890.