Rubeosaurus ovatus is a giant, herbivore centrosaurine ceratopsian dinosaur commonly called the Thornbush Lizard or Bramble because of the arrangement of its spikes.
It is believed that the reptile was an inhabitant of the two medicine formations in Montana, North America. Although a herbivore, the Thornbush Lizard is aggressive and agile and will not hesitate to attack other dinosaurs if they feel their territories are at stake.
The genus of the beast was formerly misidentified by paleontologist Gilmore, as a Styracosaurus but later investigation prompted researchers to give it a different distinct genus of its own.
However, uncertainties about the dinosaur have not been done away with. There is some speculation that the beast is actually the adult form of Brachyceratops as per Michael J Ryan.
It is unfortunate how despite the discovery of various specimens and the unearthing of many remains, the origin, genus, and classification of the animal continues to be heavily disputed even today.
For more relatable content, check out these arkansaurus and stenonychosaurus facts.
Rubeosaurus Interesting Facts
How do you pronounce 'Rubeosaurus'?
The best way to pronounce the name of this beast is to break it down into 'Roo-bee-oh-sore-us'.
What type of dinosaur was a Rubeosaurus?
Rubeosaurus ovatus is a Centrosaurine ceratopsid. Ceratopsians are four-footed, herbivorous, beaked dinosaurs with a bony frill, that lived during the Cretaceous Period in what is now North America, Europe, and Asia.
In which geological period did the Rubeosaurus roam the earth?
The ceratopsian dinosauria roamed the earth during the Campanian stage of the Cretaceous period. On the geologic timescale, the Campanian is the fifth of six eras in the Late or Upper Cretaceous Epoch. It occurred approximately 72-83 million years ago.
When did the Rubeosaurus become extinct?
The exact data of the time, when juvenile, subadult, and mature Rubeosaurus became extinct, is unrecorded or unfounded.
Only three specimens of the animal have been unearthed to date and even now the genus classification of the animal is disputed and debatable.
Vertebrate paleontologist Charles W. Gilmore identified Rubeosaurus ovatus as a new species of Styracosaurus ovatus living in the Upper Two Medicine Formation of Montana based on the partial skull and partial parietal bone of a huge centrosaurine.
Later, McDonald and Horner minutely studied the second specimen of the reptile which included complete bone structures like the left and right nasal and horncore,††‬partial left orbital with horncore, and a nearly complete right parietal with two spikes.
This investigation revealed that R. ovatus was not congeneric with the species of Styracosaurus ovatus, and thus the new genus Rubeosaurus was formed.
Where did Rubeosaurus live?
The fossil of the centrosaurine ceratopsid was discovered in what we now know as Montana, North America.
What was Rubeosaurus' habitat?
The reptile lived in a two medicine formation, which is a geological rock formation located in Montana.
The animal used to inhabit the land in the Campanian stage of the upper cretaceous period.
A major reason why the genus and classification of the R.ovatus are still confusing is that the remains of the Styracosaurus Ovatus were also found in the same habitat as stated by Andrew T. McDonald & John R. Horner, (2010) in their book 'New Material of 'Styracosaurus' ovatus from the Two Medicine Formation of Montana'.
The exact environment they lived in is unknown.
Who did Rubeosaurus live with?
Despite much research, not much is known about the company that the R.ovatus would keep. But since the beast was a herbivore, one can assume that it lived alongside other harmonious herbivores in the two medicine formations.
Some dinosaurian reptiles they could have lived with are Hadrosaurs, Monoclonius, Coronosaurus, Ankylosaurus, and Brachyceratops. Brachyceratops is also speculated to be the adult form of R.ovatus (Ryan et al, 2007).
How long did a Rubeosaurus live?
The exact data pertaining to the lifespan of the dinosaur is currently unknown. According to studies, the food habits of dinosaurs played a significant role in their longevity. Meat-eating dinosaurs had a shorter lifespan while the dinosaurs that were herbivores enjoyed a longer life.
How did they reproduce?
The female of the species would lay eggs and incubate them till they hatched. However, there have been no fossil remains of any reproductive organs of this animal, to shed light on their reproductive process.
Rubeosaurus Fun Facts
What did the Rubeosaurus look like?
Rubeosaurus ovatus is a big dinosaur. It is not very accurately known what the animal looks like but a rough sketch of the animal can be drawn based on its remains.
The specimen found of the beast shows that it has left and right nasal and horncore.
The ‬partial left orbital has a horncore while the right parietal had two prominent spikes. Like most dinosaurs that belong to the Ceratopsidae family, the R.ovatus too sports a bony frill.
The back of the neck frill has four huge spikes, the central two of which are oriented to point towards one another and the outside two of which point away from the middle. It was the unique arrangement of the spikes that convinced Andrew McDonald, and John Horner that this dinosaur was different from the Styracosaurus.
They explicitly pointed out differences between the two genera in their book New Material of "Styracosaurus" ovatus from the Two Medicine Formation of Montana.
Despite the fact that its length is unknown, the skull remains show that the horn was very broad at the base. The beast is believed to be brown in color with red streaks on the skull.
How many bones did a Rubeosaurus have?
Despite extensive research of the species by world-renowned vertebrate paleontologists like Gilmore, Andrew McDonald, and John R. Horner, it has not been possible to discover the number of bones a Thornbush Lizard had in its body.
Based on the partial skull and partial parietal bone remains and specimen found in 1928, Gilmore came to the conclusion that the Thornbush Lizard was a species of Styracosaurus ovatus.
It was the discovery of the second specimen that took the research in a whole new direction.
The second specimen was slightly more complete and consisted of various bone structures and fragments like the left and right nasal and horncore,†â€â€¬partial left orbital with horncore, left premaxilla, and a nearly complete right parietal with two spikes.†‬The discovery of the unique arrangement of spikes is what actually prompted the scientists to change the genus of the animal.
How did they communicate?
Little content is available about the exact communication process of Rubeosaurus ovatus. Like most dinosaurs, this ceratopsian too probably communicated vocally and visually. The beast may have also used its frill and spikes to engage in dialogue and communicate with the various animals they shared their habitat with during the Campanian stage of the Upper Cretaceous period.
How big was the Rubeosaurus?
Rubeosaurus size is rather humongous. The beast reached up to 13-20 ft (4-6 m) in length. It is bigger in size when compared to the Stokesosaurus in length.
How fast could a Rubeosaurus move?
Based on the remains available, it has not been possible to deduce how fast the animal is. However, it is a common belief that ceratopsian dinosaurs were strong runners.
How much did a Rubeosaurus weigh?
This particular ceratopsian shares a more or less similar weight when compared to other subspecies that belong to the Dinosauria clade Ceratopsidae. R. ovatus weighs 6,600-13,200 lb (2993.71-5987.42 kg) while Styracosaurus ovatus weighs 5952 lb (2699.78 kg).
What were the male and female names of the species?
No sex-specific name has been allocated to the Rubeosaurus ovatus (Dinosauria:Â Ceratopsidae).
What would you call a baby Rubeosaurus?
Juvenile Rubeosaurus ovatus dinosaurs, like their reptile cousins the turtles and crocodiles, are called hatchlings or juveniles.
What did they eat?
It fed on plants, roots, shoots, and stems like every other herbivorous dinosaur that lived in the two medicine formations.
How aggressive were they?
The Thornbush Lizard is believed to be nimble, aggressive, as well as territorial. Male Rubeosaurus could probably charge in like a bull, using its crest, horn, powerful feet, and tail to fend off foes. Only in battles with ravenous beasts like Rubeosaurus vs Megaraptor would the former perhaps find themselves on the losing side.
Did you know...
Michael J. Ryan speculated the R. ovatus to be the adult form of Brachyceratops, based on the remains of the incomplete juvenile specimen. However, because it is difficult to refer to more remnants of them, it is impossible to prove a formal relationship between Brachyceratops and the Montana Dinosaur.
Many research books have been written by prominent paleontologists on this elusive species.
Some of the most appreciated and well-researched books on the beast are 'New Material of 'Styracosaurus' ovatus from the Two Medicine Formation of Montana', by Andrew T. McDonald & John R. Horner, New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, by M. J. Ryan, B. J. Chinnery-Allgeier, D. A. Eberth, and A Subadult Specimen of Rubeosaurus ovatus by McDonald.
Monoclonius is a real species that might have lived in the same period as Styracosaurus.
Rubeosaurus vs Styracosaurus
In 2010, Andrew McDonald and Jack Horner proposed that the Montana dinosaur belonged to a distinct genus.
They called the reptile R. ovatus based on the fragmentary frill and other skull fragments. It happened to be another one of those strange horned dinosaurs with a large nasal horn and third parietal horns that pointed inward, rather than outward, as in Styracosaurus.
Styracosaurus shared its habitat the vast coastal plain with other dinosaurs such as hadrosaurs like Parasaurolophus, Corythosaurus, ceratopsians like Centrosaurus, and Chasmosaurus, as well as the tyrannosaurs Gorgosaurus and Albertosaurus.
The large 18 ft (5.5 m) dinosaur roamed the Earth during the Late Cretaceous Period and became extinct approximately 70-83 million years ago. It was a plant-eating, herbivore creature that survived on palms, ferns, and cycads.
The name Styracosaurus means Spiked Lizard and it gets its name from its physical appearance as it has spikes on its rear end.
Who discovered Rubeosaurus?
The remains of the animal were first examined by Gilmore but based on the preliminary examination of a partial skull and partial parietal bones he had assigned the beast to be a Styracosaurus. It was actually McDonald and Horner who identified the dinosaur and assigned them to the correct genus in 2010.
Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! For more relatable content, check out these Aquilops facts and Coronosaurus facts pages.
You can even occupy yourself at home by coloring in one of our free printable family of four dinosaurs coloring pages.
*The second image is by Nobu Tamura.
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Bachelor of Arts specializing in Journalism and Mass Communication, Postgraduate Diploma in Sports Management
Moumita DuttaBachelor of Arts specializing in Journalism and Mass Communication, Postgraduate Diploma in Sports Management
A content writer and editor with a passion for sports, Moumita has honed her skills in producing compelling match reports and stories about sporting heroes. She holds a degree in Journalism and Mass Communication from the Indian Institute of Social Welfare and Business Management, Calcutta University, alongside a postgraduate diploma in Sports Management.
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