Dinopedia
Advertisement

Total anky death
Extinct as can be!

This article contains plagiarized material! You can help Dinopedia out by adding more information to it, or removing/replacing any plagiarized content!


Styracosaurus
Temporal range: Late Cretaceous
6225449 orig
An artist's illustration of Styracosaurus albertensis
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Order: Ornithischia
Suborder: †Cerapoda
Infraorder: †Ceratopsia
Family: Ceratopsidae
Subfamily: †Centrosaurinae
Genus: Styracosaurus
Lambe, 1913
Type species
Styracosaurus albertensis
Lambe, 1913

Styracosaurus ( meaning "spiked lizard") was an herbivorous dinosaur from the Cretaceous period. It was a relative of Centrosaurus and Monoclonius. Unlike them, however, Styracosaurus had six long horns extending from its neck frill, a smaller horn above each of its eyes, and a single horn protruding from its nose at 60 centimeters (2 feet) long and 15 centimeters (6 inches) wide. It was a large dinosaur, reaching lengths of 6 meters (20 feet) and weighing as much as 4 tons. It stood about 1.8 meters (6 feet) tall.

The first fossil remains of Styracosaurus were discovered in Alberta, Canada in 1913, in an area now known as the Dinosaur Provincial Park. Other centrosaurine dinosaurs, such as Pachyrhinosaurus, were also found in that province. Like the rest of the ceratopsian dinosaurs, Styracosaurus possessed four short legs and a bulky body, and was probably able to achieve speeds of up to 32 kilometers per hour (20 miles per hour). Its tail was rather short. It also had a beak and cheek teeth, indicating that its diet was herbivorous and composed mostly of cycads, palms, and other prehistoric plants.

Like other ceratopsians, this dinosaur was most likely a herd animal, traveling in large groups and caring for its young after they hatched. Further evidence of this exists in the discovery of a bonebed in Arizona, USA with about 100 Styracosaurus fossils.

According to its Encephalization Quotient (brain to body weight ratio), the Styracosaurus was of intermediate intelligence.

DAK Styracosaurus

A Styracosaurus replica model.

Discoveries and species[]

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 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 to 5.8 meters in length and stood about 1.65 meters high at the hips. An unusual feature of this first skull is that 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. Styracosaurus "parksi" skeleton, specimen AM5372 Barnum Brown and crew, working for the American Museum of Natural History in New York, collected 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 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 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 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 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. Holotype frill of S. ovatus, which was moved to Rubeosaurus

A third species, S. ovatus, from the Two Medicine Formation of Montana, was described by Gilmore in 1930. The fossil material is limited, with the best being a portion of the parietal bone of the frill, but one unusual feature is that the pair of spikes closest to the midline converge towards the midline, rather than away from it as in S. albertensis. There also may only have been two sets of spikes on each side of the frill, instead of three. The spikes are much shorter than in S. albertensis, with the longest only 295 millimeters (11.6 inches) long. A 2010 review of styracosaur skull remains by Ryan, Holmes, and Russell found it to be a distinct species, and in 2010 McDonald and Horner placed it in its own genus, Rubeosaurus.

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, 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.

Description[]

Individuals of the genus Styracosaurus were approximately 5.5 meters (18 ft) long as adults and weighed around 2.7 tonnes. The skull was massive, with a large nostril, a tall straight nose horn, and a parietosquamosal frill (a neck frill) crowned with at least four large spikes. Each of 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.

Restoration[]

Aside from 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 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 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.

Classification[]

Styracosaurus is a member of 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 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 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.

Paleobiology[]

Styracosaurus and other horned dinosaurs are often depicted in popular culture as herd animals. A bonebed composed of Styracosaurus remains 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 semiarid.

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.

Paleoecology[]

Styracosaurus is known from the Dinosaur Park Formation, and was a member of a diverse and well-documented fauna of prehistoric animals that included horned relatives such as Centrosaurus and Chasmosaurus, duckbills such as Prosaurolophus, Lambeosaurus, Gryposaurus, Corythosaurus, and Parasaurolophus, tyrannosaurids Gorgosaurus, Daspletosaurus, and armored Edmontonia and Euoplocephalus.

The Dinosaur Park Formation is interpreted as a low-relief setting of rivers and floodplains that became more swampy and influenced by marine conditions over time as the Western Interior Seaway transgressed westward. The climate was warmer than present-day Alberta, without frost, but with wetter and drier seasons. Conifers were apparently the dominant canopy plants, with an understory of ferns, tree ferns, and angiosperms.

In popular culture[]

  • Styracosaurus appeared in Disney's Dinosaur, particularly as Eema.
  • Styracosaurus appeared in Disney Pixar's The Good Dinosaur, named Forest woodbush with his horns look resemble to a Diabloceratops.
  • Styracosaurus appeared on Dinosaur King.
  • Styracosaurus appeared on Dinosaur Train.
  • Styracosaurus appeared in the documentary Bizarre Dinosaurs.
  • Styracosaurus appeared in a Roblox game called "Dinosaur Simulator".
  • Styracosaurus appeared in a Roblox game called "Dinosaur World Mobile"
  • Styracosaurus appears in Prehistoric Kingdom.

Gallery[]

Styracosaurus/Gallery

Advertisement