Arrhinoceratops
Herbivore·Late Cretaceous·Canada·Quadrupedal
Arrhinoceratops was a herbivorous ceratopsian dinosaur that lived during the Late Cretaceous period, specifically the latest Campanian to earliest Maastrichtian stages. Known primarily from a partial skull found in Canada, its name, meaning "no nose-horn face," was based on an initial misinterpretation of its nasal structure. It predated its more famous relative, Triceratops, by a few million years.
Key Facts
- ›Arrhinoceratops lived during the Late Cretaceous, from the latest Campanian to earliest Maastrichtian stages.
- ›Its remains have been discovered in Canada, specifically from the Horseshoe Canyon Formation.
- ›The dinosaur was a herbivore, likely feeding on ferns, cycads, and conifers.
- ›Its skull featured a broad, square frill with two oval openings and moderate brow horns, but a shorter, blunter nose horn.
- ›Arrhinoceratops is considered a member of the Chasmosaurinae subfamily and is phylogenetically close to Anchiceratops.
- ›Estimated body length ranges from 4.5 to 6 meters (15 to 20 feet).
- Broad, square neck frill with two oval openings
- Frill deeply veined by arterial grooves
- Sides of frill adorned by about nine osteoderms
- Lightly scalloped rear edge of frill
- Moderately long brow horns
- Shorter and blunter nose horn than most ceratopsids
- Short and high snout
Triceratops, Anchiceratops, Torosaurus
Canada, North America
About Arrhinoceratops
Arrhinoceratops was a genus of herbivorous ceratopsian dinosaur that lived during the Late Cretaceous period. Its existence spanned the latest Campanian and earliest Maastrichtian stages, making it a contemporary of other iconic dinosaurs and slightly predating the famous Triceratops.
Discoveries and Classification
The genus Arrhinoceratops was first described by William Arthur Parks in 1925. The type species, Arrhinoceratops brachyops, is known from a partially crushed and distorted skull found in Alberta, Canada, along the Red Deer River. The generic name, meaning "no nose-horn face," stemmed from an early misunderstanding by Parks regarding the structure of the nasal horn. Further analysis revealed that this feature, or its lack of a separate ossification, was not as unique as initially believed.
Physical Characteristics
Since Arrhinoceratops is primarily known from its skull, detailed information about its overall anatomy is limited. The skull, when reconstructed, displays a broad, square neck frill featuring two oval-shaped openings. This frill is notable for its deep veining and the presence of approximately nine osteoderms along its sides, with a lightly scalloped rear edge. Its brow horns were of moderate length, but the nose horn was distinctively shorter and blunter compared to many other ceratopsids. The snout itself was short and high. Popular science estimates place its fully grown body length between 4.5 to 6 meters (15 to 20 feet) and its weight at around 1.3 tonnes (2,900 lb).
Paleobiology and Habitat
As a member of the Ceratopsidae family, Arrhinoceratops was a herbivore. Its diet likely consisted of the ferns, cycads, and conifers that dominated the landscape during the Cretaceous period. It would have used its strong, beak-like mouth to shear off vegetation. The dinosaur inhabited a wet coastal environment characterized by densely forested areas, experiencing warm summers and cool winters. Evidence suggests it may have been preyed upon by large theropods such as Albertosaurus.
Phylogeny
Arrhinoceratops is classified within the Ceratopsia, specifically belonging to the Chasmosaurinae subfamily. Modern phylogenetic analyses place it in close relation to Anchiceratops, with some earlier research suggesting it might have been a direct ancestor to Torosaurus.
Source: Wikipedia ↗
Frequently Asked Questions
What does the name Arrhinoceratops mean?
The name Arrhinoceratops means "no nose-horn face." It is derived from the Greek words "a-/α-" (no), "rhis/ῥίς" (nose), "keras/κέρας" (horn), and "-ops/ὤψ" (face). This name was given due to an initial misunderstanding of its nasal horn structure.
When did Arrhinoceratops live?
Arrhinoceratops lived during the Late Cretaceous period. Specifically, it inhabited the latest Campanian and earliest Maastrichtian stages, predating Triceratops by a few million years.
What did Arrhinoceratops eat?
Arrhinoceratops was a herbivore. It likely fed on the prevalent plants of its time, such as ferns, cycads, and conifers, using its sharp beak to bite off vegetation.
Where were Arrhinoceratops fossils found?
The primary remains of Arrhinoceratops, including its holotype skull, were discovered in Canada. They were found along the Red Deer River in Alberta, within the Horseshoe Canyon Formation.
What are the key physical features of Arrhinoceratops?
Knowledge of Arrhinoceratops's physical characteristics is mainly from its skull. It possessed a broad, square neck frill with two large openings, moderately long brow horns, and a shorter, blunter nose horn. Its snout was short and high, and its body is assumed to be typical of other Ceratopsidae.
Is Arrhinoceratops related to Triceratops?
Yes, Arrhinoceratops is a relative of Triceratops. It lived a few million years before Triceratops and is also classified within the Ceratopsidae family.
Related Dinosaur species
Abditosaurus
Abditosaurus is an extinct genus of titanosaurian sauropod dinosaur that lived during the Late Cretaceous period in what is now Catalonia, Spain. It is known from the most complete titanosaur skeleton ever discovered in Europe, representing a large species that inhabited the Ibero-Armorican Island. Phylogenetic analyses suggest it was related to South American and African saltasaurines, distinguishing it from other European dwarf sauropods.
Acantholipan
Acantholipan is a genus of herbivorous nodosaurid dinosaur discovered in Mexico. It lived during the early Santonian age of the Late Cretaceous period and is known from fragmentary fossils, including a partial skeleton with osteoderms. Acantholipan gonzalezi is the type species, named in honor of paleontologist Arturo Homero González-González.
Acanthopholis
Acanthopholis is a genus of herbivorous ankylosaurian dinosaur belonging to the family Nodosauridae. It lived during the Late Cretaceous Period in England and is characterized by its distinctive armor, including keeled plates and prominent spikes along its neck and shoulders. The genus name translates to "spiny scales."