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84-536: Centrosaurus ( / ˌ s ɛ n t r oʊ ˈ s ɔːr ə s / SEN -troh- SOR -əs ; lit.   ' pointed lizard ' ) is a genus of centrosaurine ceratopsian dinosaur from Campanian age of Late Cretaceous Canada . Their remains have been found in the Dinosaur Park Formation , dating from 76.5 to 75.5 million years ago. The first Centrosaurus remains were discovered and named by paleontologist Lawrence Lambe in strata along

168-458: A continent." Genus The composition of a genus is determined by taxonomists . The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: Moreover, genera should be composed of phylogenetic units of

252-585: A female Styracosaurus or Monoclonius as a valid genus. While sexual dimorphism has been proposed for a more basal ceratopsian, Protoceratops , there is no firm evidence for sexual dimorphism in any ceratopsid. Others have synonymized C. nasicornus with C. apertus , or considered it a separate Centrosaurus species: Centrosaurus nasicornus . It has also been suggested as the direct ancestor of Styracosaurus albertensis . A 2014 study of changes during growth in Centrosaurus concluded that C. nasicornus

336-1095: A female Styracosaurus , instead regarding it as a synonym of Centrosaurus apertus . While sexual dimorphism has been proposed for an earlier ceratopsian, Protoceratops , there is no firm evidence for sexual dimorphism in any ceratopsid. The cladogram depicted below represents a phylogenetic analysis by Chiba et al. (2017): Diabloceratops eatoni Machairoceratops cronusi Avaceratops lammersi (ANSP 15800) MOR 692 CMN 8804 Nasutoceratops titusi Malta new taxon Xenoceratops foremostensis Sinoceratops zhuchengensis Wendiceratops pinhornensis Albertaceratops nesmoi Medusaceratops lokii Rubeosaurus ovatus Styracosaurus albertensis Coronosaurus brinkmani Centrosaurus apertus Spinops sternbergorum Einiosaurus procurvicornis Achelousaurus horneri Pachyrhinosaurus canadensis Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum The evolutionary origins of Styracosaurus were not understood for many years because fossil evidence for early ceratopsians

420-548: A flooded river. A discovery of thousands of Centrosaurus fossils near the town of Hilda , Alberta , is believed to be the largest bed of dinosaur bones ever discovered. The area is now known as the Hilda mega-bonebed . Because of the variation between species and even individual specimens of centrosaurines, there has been much debate over which genera and species are valid, particularly whether Centrosaurus and/or Monoclonius are valid genera, undiagnosable, or possibly members of

504-651: A later homonym of a validly published name is a nomen illegitimum or nom. illeg. ; for a full list refer to the International Code of Nomenclature for algae, fungi, and plants and the work cited above by Hawksworth, 2010. In place of the "valid taxon" in zoology, the nearest equivalent in botany is " correct name " or "current name" which can, again, differ or change with alternative taxonomic treatments or new information that results in previously accepted genera being combined or split. Prokaryote and virus codes of nomenclature also exist which serve as

588-628: A long time and redescribed as new by a range of subsequent workers, or if a range of genera previously considered separate taxa have subsequently been consolidated into one. For example, the World Register of Marine Species presently lists 8 genus-level synonyms for the sperm whale genus Physeter Linnaeus, 1758, and 13 for the bivalve genus Pecten O.F. Müller, 1776. Within the same kingdom, one generic name can apply to one genus only. However, many names have been assigned (usually unintentionally) to two or more different genera. For example,

672-438: A mix of animals, and nondiagnostic ceratopsian remains). Bonebed 42 is known to contain numerous pieces of skulls such as horncores, jaws and frill pieces. Several other species which were assigned to Styracosaurus have since been assigned to other genera. S. sphenocerus , described by Edward Drinker Cope in 1890 as a species of Monoclonius and based on a nasal bone with a broken Styracosaurus -like straight nose horn,

756-487: A nearly complete articulated skeleton with a partial skull in 1915. These fossils were also found in the Dinosaur Park Formation, near Steveville , Alberta. Brown and Erich Maren Schlaikjer compared the finds, and, though they allowed that both specimens were from the same general locality and geological formation, they considered the specimen sufficiently distinct from the holotype to warrant erecting

840-457: A new genus, Rubeosaurus , by Andrew McDonald and Jack Horner in 2010, but it has been considered either its own genus or a species of Styracosaurus (or even a specimen of S. albertensis ) again, since 2020. The first fossil remains of Styracosaurus were collected in Alberta , Canada by C. M. Sternberg (from an area now known as Dinosaur Provincial Park , in a formation now called

924-417: A new species, and described the fossils as Styracosaurus parksi , named in honor of William Parks . Among the differences between the specimens cited by Brown and Schlaikjer were a cheekbone quite different from that of S. albertensis , and smaller tail vertebrae . S. parksi also had a more robust jaw, a shorter dentary , and the frill differed in shape from that of the type species. However, much of

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1008-465: A partial parietal under the accession number USNM 11869. Unlike S. albertensis , the longest parietal spikes converge towards their tips, instead of projecting parallel behind the frill. There also may only have been two sets of spikes on each side of the frill, instead of three. As estimated from the preserved material, the spikes are much shorter than in S. albertensis , with the longest only 295 millimeters (11.6 inches) long. An additional specimen from

1092-409: A reference for designating currently accepted genus names as opposed to others which may be either reduced to synonymy, or, in the case of prokaryotes, relegated to a status of "names without standing in prokaryotic nomenclature". An available (zoological) or validly published (botanical) name that has been historically applied to a genus but is not regarded as the accepted (current/valid) name for

1176-405: A relatively short tail. Each toe bore a hooflike ungual which was sheathed in horn. Various limb positions have been proposed for Styracosaurus and ceratopsids in general, including forelegs which were held underneath the body, or, alternatively, held in a sprawling position. The most recent work has put forward an intermediate crouched position as most likely. Styracosaurus is a member of

1260-536: A series of fossil skulls from the Two Medicine Formation of Montana. The position of Styracosaurus in this lineage is now equivocal, as the remains that were thought to represent Styracosaurus have been transferred to the genus Rubeosaurus . Styracosaurus is known from a higher position in the formation (relating specifically to its own genus) than the closely related Centrosaurus , suggesting that Styracosaurus displaced Centrosaurus as

1344-522: A similar result to McDonald and Horner when the specimen was included as part of the S. ovatus hypodigm. Wilson and colleagues also suggested that the new taxon may have been ancestral to the later forms it was found related to, suggesting that gradual evolution through anagenesis could be the reason for the intermediate morphologies of many specimens and species found in the Two Medicine Formation, possibly also including S. ovatus . As

1428-448: A single large horn over their noses. These horns curved forwards or backwards depending on the specimen. Skull ornamentation was reduced as animals aged. The frill was relatively short compared to the total skull length and could grow to over half a meter (68.8 cm) long in the oldest and largest adults. Centrosaurus is distinguished by having two large hornlets which hook forwards over the frill. A pair of small upwards directed horns

1512-427: A taxon; however, the names published in suppressed works are made unavailable via the relevant Opinion dealing with the work in question. In botany, similar concepts exist but with different labels. The botanical equivalent of zoology's "available name" is a validly published name . An invalidly published name is a nomen invalidum or nom. inval. ; a rejected name is a nomen rejiciendum or nom. rej. ;

1596-455: A total of c. 520,000 published names (including synonyms) as at end 2019, increasing at some 2,500 published generic names per year. "Official" registers of taxon names at all ranks, including genera, exist for a few groups only such as viruses and prokaryotes, while for others there are compendia with no "official" standing such as Index Fungorum for fungi, Index Nominum Algarum and AlgaeBase for algae, Index Nominum Genericorum and

1680-425: A unique combination of parietal features only shared completely with the other specimens of the species. Though it was originally found to nest closer to Einiosaurus and later centrosaurines by McDonald and colleagues in both 2010 and 2011, revisions of phylogenetic analyses in 2013 by Scott Sampson and colleagues, and further expansions and modifications of the same dataset, instead placed Rubeosaurus ovatus as

1764-445: A waterhole during a drought. Centrosaurus is found lower in the formation than Styracosaurus , indicating that Centrosaurus was displaced by Styracosaurus as the environment changed over time. The large frills and nasal horns of the ceratopsians are among the most distinctive facial adornments of all dinosaurs. Their function has been the subject of debate since the first horned dinosaurs were discovered. Common theories concerning

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1848-427: A way that contrasted McDonald and Horner who referred it to Styracosaurus ovatus . While Wilson et al. agreed that the close relationship between S. albertensis and S. ovatus meant that the genus name Rubeosaurus should be abandoned, they cautioned against synonymization. MOR 492 was moved into its own taxon, Stellasaurus ancellae , which nested alongside Einiosaurus , Achelousaurus and Pachyrhinosaurus in

1932-437: Is a junior synonym of C. apertus , representing a middle growth stage. The species C. brinkmani , described in 2005, was moved to the new genus Coronosaurus in 2012. Centrosaurus were large dinosaurs, although not as large as some of their relatives, reaching 5–5.5 metres (16–18 ft) long and 2–2.5 metric tons (2.2–2.8 short tons) in body mass situated atop stocky limbs. Like other centrosaurines, Centrosaurus bore

2016-469: Is also found over the eyes. The frills of Centrosaurus were moderately long, with fairly large fenestrae and small hornlets along the outer edges. The genus Centrosaurus gives its name to the Centrosaurinae subfamily. Its closest relatives appear to be Styracosaurus and Monoclonius . It so closely resembles the latter of these that some paleontologists have considered them to represent

2100-476: Is an extinct genus of herbivorous ceratopsian dinosaur from the Late Cretaceous ( Campanian stage ) of North America. It had four to six long parietal spikes extending from its neck frill , a smaller jugal horn on each of its cheeks, and a single horn protruding from its nose, which may have been up to 60 centimeters (2 feet) long and 15 centimeters (6 inches) wide. The function or functions of

2184-479: Is derived from the same Greek word. Later, vast bonebeds of Centrosaurus were found in Dinosaur Provincial Park , also in Alberta . Some of these beds extend for hundreds of meters and contain thousands of individuals of all ages and all levels of completion. Scientists have speculated that the high density and number of individuals would be explained if they had perished while trying to cross

2268-612: Is discouraged by both the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants , there are some five thousand such names in use in more than one kingdom. For instance, A list of generic homonyms (with their authorities), including both available (validly published) and selected unavailable names, has been compiled by the Interim Register of Marine and Nonmarine Genera (IRMNG). The type genus forms

2352-713: Is known from the Dinosaur Park Formation of Alberta, about halfway up the formation. This bonebed is associated with different types of river deposits. The mass deaths may have been a result of otherwise non-herding animals congregating around a waterhole in a period of drought, with evidence suggesting the environment may have been seasonal and semi-arid. Paleontologists Gregory Paul and Per Christiansen proposed that large ceratopsians such as Styracosaurus were able to run faster than an elephant , based on possible ceratopsian trackways which did not exhibit signs of sprawling forelimbs. Styracosaurs were herbivorous dinosaurs; they probably fed mostly on low growth because of

2436-460: Is somewhat arbitrary. Although all species within a genus are supposed to be "similar", there are no objective criteria for grouping species into genera. There is much debate among zoologists about whether enormous, species-rich genera should be maintained, as it is extremely difficult to come up with identification keys or even character sets that distinguish all species. Hence, many taxonomists argue in favor of breaking down large genera. For instance,

2520-474: Is the type species , and the generic name is permanently associated with the type specimen of its type species. Should the specimen turn out to be assignable to another genus, the generic name linked to it becomes a junior synonym and the remaining taxa in the former genus need to be reassessed. In zoological usage, taxonomic names, including those of genera, are classified as "available" or "unavailable". Available names are those published in accordance with

2604-635: The Centrosaurinae . Other members of the clade include Centrosaurus (from which the group takes its name), Pachyrhinosaurus , Avaceratops , Einiosaurus , Albertaceratops , Achelousaurus , Brachyceratops , and Monoclonius , although these last two are dubious . Because of the variation between species and even individual specimens of centrosaurines, there has been much debate over which genera and species are valid, particularly whether Centrosaurus and/or Monoclonius are valid genera, undiagnosable, or possibly members of

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2688-767: The Centrosaurus bone bed where it was found. The specimen remains one of the few dinosaur specimens found with severe cancer. Thomas M. Lehman has observed that Centrosaurus fossils haven't been found outside of southern Alberta even though they are among the most abundant Judithian dinosaurs in the region. Large herbivores like the ceratopsians living in North America during the Late Cretaceous had "remarkably small geographic ranges" despite their large body size and high mobility. This restricted distribution strongly contrasts with modern mammalian faunas whose large herbivores' ranges "typical[ly] ... span much of

2772-400: The Dinosaur Park Formation ) and named by Lawrence Lambe in 1913. This quarry was revisited in 1935 by a Royal Ontario Museum crew who found the missing lower jaws and most of the skeleton. These fossils indicate that S. albertensis was around 5.5–5.8 metres (18–19 ft) in length and stood about 1.65 metres (5.4 ft) high at the hips. An unusual feature of this first skull is that

2856-621: The International Code of Zoological Nomenclature ; the earliest such name for any taxon (for example, a genus) should then be selected as the " valid " (i.e., current or accepted) name for the taxon in question. Consequently, there will be more available names than valid names at any point in time; which names are currently in use depending on the judgement of taxonomists in either combining taxa described under multiple names, or splitting taxa which may bring available names previously treated as synonyms back into use. "Unavailable" names in zoology comprise names that either were not published according to

2940-824: The International Plant Names Index for plants in general, and ferns through angiosperms, respectively, and Nomenclator Zoologicus and the Index to Organism Names for zoological names. Totals for both "all names" and estimates for "accepted names" as held in the Interim Register of Marine and Nonmarine Genera (IRMNG) are broken down further in the publication by Rees et al., 2020 cited above. The accepted names estimates are as follows, broken down by kingdom: The cited ranges of uncertainty arise because IRMNG lists "uncertain" names (not researched therein) in addition to known "accepted" names;

3024-478: The Red Deer River in Alberta . The name Centrosaurus means "pointed lizard" (from Greek kentron , κέντρον , "point" and sauros , σαῦρος , "lizard") and refers to, the series of small hornlets placed along the margin of their frills, not the nasal horns (which were unknown when the dinosaur was named). The genus is not to be confused with the stegosaur Kentrosaurus , the name of which

3108-420: The cancer had reached an aggressive stage. The cancer would have resulted in a severe limp that would have made the ceratopsian more vulnerable to predation. However, the fact that it was part of a herd allowed the Centrosaurus to survive much longer than would be expected for an animal infected with such severe disease. The individual itself is believed to have died from drowning in the flash flood that created

3192-419: The nomenclature codes , which allow each species a single unique name that, for animals (including protists ), plants (also including algae and fungi ) and prokaryotes ( bacteria and archaea ), is Latin and binomial in form; this contrasts with common or vernacular names , which are non-standardized, can be non-unique, and typically also vary by country and language of usage. Except for viruses ,

3276-404: The platypus belongs to the genus Ornithorhynchus although George Shaw named it Platypus in 1799 (these two names are thus synonyms ) . However, the name Platypus had already been given to a group of ambrosia beetles by Johann Friedrich Wilhelm Herbst in 1793. A name that means two different things is a homonym . Since beetles and platypuses are both members of the kingdom Animalia,

3360-489: The Two Medicine Formation was referred to Styracosaurus ovatus in 2010 by Andrew McDonald and John Horner , having been found earlier in 1986 but not described until that year. Known from a premaxilla , the nasal bones and their horncore, a postorbital bone and a parietal, the specimen Museum of the Rockies 492 was considered to share the medially-converging parietal spikes with the only other specimen of S. ovatus ,

3444-405: The animal sliced up plants. Like other ceratopsians, this dinosaur may have been a herd animal , travelling in large groups, as suggested by bone beds . Named by Lawrence Lambe in 1913, Styracosaurus is a member of the Centrosaurinae . One species , S. albertensis , is currently assigned to Styracosaurus . Another species, S. ovatus , named in 1930 by Charles Gilmore was reassigned to

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3528-442: The base for higher taxonomic ranks, such as the family name Canidae ("Canids") based on Canis . However, this does not typically ascend more than one or two levels: the order to which dogs and wolves belong is Carnivora ("Carnivores"). The numbers of either accepted, or all published genus names is not known precisely; Rees et al., 2020 estimate that approximately 310,000 accepted names (valid taxa) may exist, out of

3612-477: The distinction of Styracosaurus ovatus , with Holmes et al. considering the latter a junior synonym of the former. The conclusion of Holmes and colleagues was supported by a later 2020 study authored by Caleb Brown, Holmes, and Philip J. Currie , who described a new juvenile Styracosaurus specimen and determined that there were several specimens that are otherwise consistent with S. albertensis have been found with inward angled midline frill spikes, though not

3696-460: The environment changed over time and/or dimension. It has been suggested that Styracosaurus albertensis is a direct descendant of Centrosaurus ( C. apertus or C. nasicornis ), and that it in turn evolved directly into the slightly later species Rubeosaurus ovatus . Subtle changes can be traced in the arrangement of the horns through this lineage, leading from Rubeosaurus to Einiosaurus , to Achelousaurus and Pachyrhinosaurus . However,

3780-446: The form "author, year" in zoology, and "standard abbreviated author name" in botany. Thus in the examples above, the genus Canis would be cited in full as " Canis Linnaeus, 1758" (zoological usage), while Hibiscus , also first established by Linnaeus but in 1753, is simply " Hibiscus L." (botanical usage). Each genus should have a designated type , although in practice there is a backlog of older names without one. In zoology, this

3864-423: The four longest frill spines was comparable in length to the nose horn, at 50 to 55 centimeters (20 to 22 inches) long. The nasal horn was estimated by Lambe at 57 centimeters (22 inches) long in the type specimen, but the tip had not been preserved. Based on other nasal horn cores from Styracosaurus and Centrosaurus , this horn may have come to a more rounded point at around half of that length. Aside from

3948-422: The function of ceratopsian frills and horns include defense from predators, combat within the species, and visual display. A 2009 study of Triceratops and Centrosaurus skull lesions found that bone injuries on the skulls were more likely caused by intraspecific combat (horn-to-horn combat) rather than predatory attacks. The frills of Centrosaurus were too thin to be used for defense against predators, although

4032-737: The generic name (or its abbreviated form) still forms the leading portion of the scientific name, for example, Canis lupus lupus for the Eurasian wolf subspecies, or as a botanical example, Hibiscus arnottianus ssp. immaculatus . Also, as visible in the above examples, the Latinised portions of the scientific names of genera and their included species (and infraspecies, where applicable) are, by convention, written in italics . The scientific names of virus species are descriptive, not binomial in form, and may or may not incorporate an indication of their containing genus; for example,

4116-500: The holotype of Styracosaurus ovatus was found in deposits much younger than the remainder of Styracosaurus specimens, and was considered to have the most extreme morphology while still falling within plausible variation as Holmes et al. had concluded, Wilson and colleagues advised that S. ovatus was retained as a separate, probably directly descended from S. albertensis , species of Styracosaurus . The immature specimen USNM 14768, referred to S. ovatus by McDonald et al. in 2011,

4200-399: The holotype. Following this additional material, the species was added to a phylogenetic analysis where it was found to group not with Styracosaurus albertensis , but in a clade including Pachyrhinosaurus , Einiosaurus and Achelousaurus , and therefore McDonald and Horner gave the species the new genus name Rubeosaurus . Another specimen, the partial immature skull USNM 14768, which

4284-450: The horns and frills have been debated for many years. Styracosaurus was a relatively large dinosaur, reaching lengths of 5–5.5 metres (16–18 ft) and weighing about 1.8–2.7 metric tons (2.0–3.0 short tons). It stood about 1.8 meters (5.9 feet) tall. Styracosaurus possessed four short legs and a bulky body. Its tail was rather short. The skull had a beak and shearing cheek teeth arranged in continuous dental batteries , suggesting that

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4368-498: The jaws of Centrosaurus were adapted to shear through tough plant material. The discovery of gigantic bone beds of Centrosaurus in Canada suggest that they were gregarious animals and could have traveled in large herds. A bone bed composed of Centrosaurus and Styracosaurus remains is known from the Dinosaur Park Formation in what is now Alberta. The mass deaths may have been caused by otherwise non-herding animals gathering around

4452-410: The large nasal horn and four long frill spikes, the cranial ornamentation was variable. Some individuals had small hook-like projections and knobs at the posterior margin of the frill, similar to but smaller than those in Centrosaurus . Others had less prominent tabs. Some, like the type individual, had a third pair of long frill spikes. Others had much smaller projections, and small points are found on

4536-633: The largest component, with 23,236 ± 5,379 accepted genus names, of which 20,845 ± 4,494 are angiosperms (superclass Angiospermae). By comparison, the 2018 annual edition of the Catalogue of Life (estimated >90% complete, for extant species in the main) contains currently 175,363 "accepted" genus names for 1,744,204 living and 59,284 extinct species, also including genus names only (no species) for some groups. The number of species in genera varies considerably among taxonomic groups. For instance, among (non-avian) reptiles , which have about 1180 genera,

4620-573: The lineage may not be a simple, straight line, as a pachyrhinosaur-like species has been reported from the same time and place as Styracosaurus albertensis . In 2020, during the description of Stellasaurus , Wilson et al. found Styracosaurus (including S. ovatus ) to be the earliest member of a single evolutionary lineage that eventually developed into Stellasaurus , Achelousaurus , and Pachyrhinosaurus . Styracosaurus and other horned dinosaurs are often depicted in popular culture as herd animals. A bonebed composed of Styracosaurus remains

4704-508: The lizard genus Anolis has been suggested to be broken down into 8 or so different genera which would bring its ~400 species to smaller, more manageable subsets. Styracosaurus Styracosaurus ( / s t ɪ ˌ r æ k ə ˈ s ɔːr ə s / sti- RAK -ə- SOR -əs ; meaning "spiked lizard" from the Ancient Greek styrax / στύραξ "spike at the butt-end of a spear-shaft" and sauros / σαῦρος "lizard")

4788-403: The most (>300) have only 1 species, ~360 have between 2 and 4 species, 260 have 5–10 species, ~200 have 11–50 species, and only 27 genera have more than 50 species. However, some insect genera such as the bee genera Lasioglossum and Andrena have over 1000 species each. The largest flowering plant genus, Astragalus , contains over 3,000 species. Which species are assigned to a genus

4872-430: The most distinctive facial adornments of all dinosaurs. Their function has been the subject of debate since the first horned dinosaurs were discovered. Early in the 20th century, paleontologist R. S. Lull proposed that the frills of ceratopsian dinosaurs acted as anchor points for their jaw muscles. He later noted that for Styracosaurus , the spikes would have given it a formidable appearance. In 1996, Dodson supported

4956-428: The name could not be used for both. Johann Friedrich Blumenbach published the replacement name Ornithorhynchus in 1800. However, a genus in one kingdom is allowed to bear a scientific name that is in use as a generic name (or the name of a taxon in another rank) in a kingdom that is governed by a different nomenclature code. Names with the same form but applying to different taxa are called "homonyms". Although this

5040-474: The older deposits of the Dinosaur Park Formation S. albertensis is known from. While no phylogenetic analysis was conducted, previous results of updated analyses showed that Rubeosaurus ovatus and Styracosaurus albertensis were not distantly related, so the justification for naming the genus Rubeosaurus was not present, and the variability in Styracosaurus albertensis specimens also did not support

5124-475: The opposite sex. In 1996, Peter Dodson found enough variation between Centrosaurus , Styracosaurus , and Monoclonius to warrant separate genera and that Styracosaurus resembled Centrosaurus more closely than either resembled Monoclonius . Dodson believed one species of Monoclonius , M. nasicornus , may actually have been a female Styracosaurus . His assessments have been partially followed, with other researchers not accepting Monoclonius nasicornus as

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5208-447: The opposite sex. In 1996, Peter Dodson found enough variation between Centrosaurus , Styracosaurus , and Monoclonius to warrant separate genera, and that Styracosaurus resembled Centrosaurus more closely than either resembled Monoclonius . Dodson also believed one species of Monoclonius , M. nasicornis , may actually have been a female Styracosaurus . However, most other researchers have not accepted Monoclonius nasicornis as

5292-511: The origins of horned dinosaurs in general, and suggest that the group originated during the Jurassic in Asia, with the appearance of true horned ceratopsians occurring by the beginning of the late Cretaceous in North America. Goodwin and colleagues proposed in 1992 that Styracosaurus was part of the lineage leading to Einiosaurus , Achelousaurus and Pachyrhinosaurus . This was based on

5376-850: The position of the head. They may, however, have been able to knock down taller plants with their horns, beak , and bulk. The jaws were tipped with a deep, narrow beak, believed to have been better at grasping and plucking than biting. Ceratopsid teeth, including those of Styracosaurus , were arranged in groups called batteries. Older teeth on top were continually replaced by the teeth underneath them. Unlike hadrosaurids , which also had dental batteries, ceratopsid teeth sliced but did not grind. Some scientists have suggested that ceratopsids like Styracosaurus ate palms and cycads , while others have suggested ferns . Dodson has proposed that Late Cretaceous ceratopsians may have knocked down angiosperm trees and then sheared off leaves and twigs. The large nasal horns and frills of Styracosaurus are among

5460-541: The provisions of the ICZN Code, e.g., incorrect original or subsequent spellings, names published only in a thesis, and generic names published after 1930 with no type species indicated. According to "Glossary" section of the zoological Code, suppressed names (per published "Opinions" of the International Commission of Zoological Nomenclature) remain available but cannot be used as the valid name for

5544-514: The quarry. These were collected and it is hoped more pieces will be found, perhaps enough to warrant a redescription of the skull and test whether S. albertensis and S. parksi are the same. The Tyrrell Museum has also collected several partial Styracosaurus skulls. At least one confirmed bone bed (bonebed 42) in Dinosaur Provincial Park has also been explored (other proposed Styracosaurus bone beds instead have fossils from

5628-917: The same animal. Other members of the Centrosaurinae subfamily include Pachyrhinosaurus , Avaceratops , Einiosaurus , Albertaceratops , and Achelousaurus . The cladogram presented below represents a phylogenetic analysis by Chiba et al. (2017): Diabloceratops eatoni Machairoceratops cronusi Avaceratops lammersi (ANSP 15800) MOR 692 CMN 8804 Nasutoceratops titusi Malta new taxon Xenoceratops foremostensis Sinoceratops zhuchengensis Wendiceratops pinhornensis Albertaceratops nesmoi Medusaceratops lokii Rubeosaurus ovatus Styracosaurus albertensis Coronosaurus brinkmani Centrosaurus apertus Spinops sternbergorum Einiosaurus procurvicornis Achelousaurus horneri Pachyrhinosaurus canadensis Pachyrhinosaurus lakustai Pachyrhinosaurus perotorum Like other ceratopsids ,

5712-415: The same degree as S. ovatus . Though they considered that S. ovatus represented an extreme end of the S. albertensis variation not only in morphology but also as it was stratigraphically younger, they cautioned that at the least the current diagnosis of S. ovatus was inadequate. Later in 2020, the supposed specimen MOR 492 was redescribed by John Wilson and colleagues, who reinterpreted its anatomy in

5796-470: The same kind as other (analogous) genera. The term "genus" comes from Latin genus , a noun form cognate with gignere ('to bear; to give birth to'). The Swedish taxonomist Carl Linnaeus popularized its use in his 1753 Species Plantarum , but the French botanist Joseph Pitton de Tournefort (1656–1708) is considered "the founder of the modern concept of genera". The scientific name (or

5880-408: The scientific epithet) of a genus is also called the generic name ; in modern style guides and science, it is always capitalised. It plays a fundamental role in binomial nomenclature , the system of naming organisms , where it is combined with the scientific name of a species : see Botanical name and Specific name (zoology) . The rules for the scientific names of organisms are laid down in

5964-449: The side margins of some but not all specimens. Modest pyramid-shaped brow horns were present in subadults, but were replaced by pits in adults. Like most ceratopsids, Styracosaurus had large fenestrae (skull openings) in its frill. The front of the mouth had a toothless beak. The bulky body of Styracosaurus resembled that of a rhinoceros . It had powerful shoulders which may have been useful in intraspecies combat. Styracosaurus had

6048-425: The sister taxon of Styracosaurus albertensis , as had been originally considered when the species was first named, though the two species were not moved into the same genus as originally named. A review of the variability within known Styracosaurus specimens by Robert Holmes and colleagues in 2020 found that USNM 11869, the type specimen of Rubeosaurus ovatus , fell within the variation seen in other specimens from

6132-531: The skull consisted of plaster reconstruction, and the original 1937 paper did not illustrate the actual skull bones. It is now accepted as a specimen of S. albertensis . In the summer of 2006, Darren Tanke of the Royal Tyrrell Museum of Palaeontology in Drumheller , Alberta relocated the long lost S. parksi site. Pieces of the skull, evidently abandoned by the 1915 crew, were found in

6216-562: The smallest frill spike on the left side is partially overlapped at its base by the next spike. It appears that the frill suffered a break at this point in life and was shortened by about 6 centimeters (2.4 inches). The normal shape of this area is unknown because the corresponding area of the right side of the frill was not recovered. Barnum Brown and crew, working for the American Museum of Natural History in New York, collected

6300-497: The specific name particular to the wolf. A botanical example would be Hibiscus arnottianus , a particular species of the genus Hibiscus native to Hawaii. The specific name is written in lower-case and may be followed by subspecies names in zoology or a variety of infraspecific names in botany . When the generic name is already known from context, it may be shortened to its initial letter, for example, C. lupus in place of Canis lupus . Where species are further subdivided,

6384-412: The standard format for a species name comprises the generic name, indicating the genus to which the species belongs, followed by the specific epithet, which (within that genus) is unique to the species. For example, the gray wolf 's scientific name is Canis lupus , with Canis ( Latin for 'dog') being the generic name shared by the wolf's close relatives and lupus (Latin for 'wolf') being

6468-403: The taxon is termed a synonym ; some authors also include unavailable names in lists of synonyms as well as available names, such as misspellings, names previously published without fulfilling all of the requirements of the relevant nomenclatural code, and rejected or suppressed names. A particular genus name may have zero to many synonyms, the latter case generally if the genus has been known for

6552-414: The thicker, solid frills of Triceratops might have evolved to protect their necks. The frills of Centrosaurus were most likely used "for species recognition and/or other forms of visual display". A specimen of Centrosaurus apertus recovered from Dinosaur Provincial Park in 1989 was discovered to have crippling osteosarcoma in its right fibula. Examination of the cancerous lesions in the bone suggest

6636-576: The values quoted are the mean of "accepted" names alone (all "uncertain" names treated as unaccepted) and "accepted + uncertain" names (all "uncertain" names treated as accepted), with the associated range of uncertainty indicating these two extremes. Within Animalia, the largest phylum is Arthropoda , with 151,697 ± 33,160 accepted genus names, of which 114,387 ± 27,654 are insects (class Insecta). Within Plantae, Tracheophyta (vascular plants) make up

6720-429: The virus species " Salmonid herpesvirus 1 ", " Salmonid herpesvirus 2 " and " Salmonid herpesvirus 3 " are all within the genus Salmonivirus ; however, the genus to which the species with the formal names " Everglades virus " and " Ross River virus " are assigned is Alphavirus . As with scientific names at other ranks, in all groups other than viruses, names of genera may be cited with their authorities, typically in

6804-400: Was attributed to Styracosaurus in 1915. "S. makeli", mentioned informally by amateur paleontologists Stephen and Sylvia Czerkas in 1990 in a caption to an illustration, is an early name for Einiosaurus . "S. borealis" is an early informal name for S. parksi . A species, Styracosaurus ovatus , from the Two Medicine Formation of Montana , was described by Gilmore in 1930, named for

6888-446: Was considered too immature to be diagnostic, and thus S. ovatus was limited to its holotype USNM 11869. Individuals of the genus Styracosaurus were approximately 5–5.5 metres (16–18 ft) long as adults and weighed about 1.8–2.7 metric tons (2.0–3.0 short tons). The skull was massive, with a large nostril , a tall straight nose horn, and a parietal squamosal frill (a neck frill ) crowned with at least four large spikes. Each of

6972-401: Was earlier referred to the undiagnostic genus Brachyceratops , was also referred to Rubeosaurus ovatus by McDonald and colleagues in 2011 . While the medial spikes of USNM 14768 were too incomplete to show if it shared the convergence seen in other R. ovatus specimens, it was considered to be the same species as it was also found in the older deposits of the Two Medicine Formation, and had

7056-491: Was sparse. The discovery of Protoceratops , in 1922, shed light on early ceratopsid relationships, but several decades passed before additional finds filled in more of the blanks. Fresh discoveries in the late 1990s and 2000s, including Zuniceratops , the earliest known ceratopsian with brow horns, and Yinlong , the first-known Jurassic ceratopsian, indicate what the ancestors of Styracosaurus may have looked like. These new discoveries have been important in illuminating

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