What is a Chasmosaurus?
Chasmosaurus belli was a dinosaur that lived in North America, several million years before the related specimen known as Triceratops. It was smaller than this one. Its name refers to the large openings observable in its collar.
It stood out for having small, blunt horns, compared to more popular ceratopsians such as Triceratops. It was quadruped, had a prominent jaw and three horns on its long face.
The length of the horns on their faces varied depending on sex in two types of Chasmosaurus. Added to these is that he had a ruffle around his neck that was particular. Its shape was square and it had a canopy of bone and skin. It extended over his neck and part of his back.
Specialists suggest that he used it in mating rituals. During the time when they were looking for a mate, they could change color, or they would even use it to identify themselves with other members of their pack. This structure would also be a deterrent to a possible attacker.
In the same way, it has been suggested that its steering wheel functioned as a body thermoregulation device.
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Finding of the Chasmosaurus
Lawrence M. Lambe described three ceratopsians found in Alberta in 1902. He designated them as members of the Monoclonius family and called them Monoclonius dawsoni, Monoclonius canadensis and Monoclonius belli.
Later it would be known that none of them actually belonged to this family. One of the specimens was a Centrosaurusanother was about a Eoceratops and the third was renamed as Protosaurus By himself Lambe.
In 1914 Lambe noticed that it had already been called Protosaurus to a species of reptile. That’s why he called him Chasmosaurus belliwhich is the one that is currently in force.
Charles Mortram Sternberg, who was a fossil collector and paleontologist, while visiting the National Museum of Canada, observed the structure of two skeletons. He noticed that one was bigger than the other.
His observations led him to notice that one had a heavier build than the other. He concluded that this physical difference was related to the sex of the animals. He understood that the smaller skeleton was male and that the larger one was that of a female.
Later in 1933 Barnum Brown described a skull found in 1913, which he called Chasmosaurus kaiseni. It had similarities with that of Chasmosaurus belliexcept for the fact that it had larger eyebrow horns.
That same year, a skull found in 1926 was also analyzed and was also assigned to the family. Chasmosaurinae. The head was smaller than that of Chasmosaurus kaiseni, but maintained the necessary characteristics to consider it a relative. He named it as Chasmosaurus brevirostris.
Another important analysis occurred in 1940 when studying a skull discovered in 1938. It boasted a large nasal horn with eyebrow horns that were smaller than in the other Chasmosaurus individuals that were previously identified.
Anyway he was placed within the family Chasmosaurus as Chasmosaurus russelli. Efforts were made to consolidate the species, explaining the variations based on sexual differences or ages, or arguing the small variations common to all specimens.
However, another Ceratosian was found in 1938 that was clearly different from Chasmosaurus. When studying it, scientists saw more characteristics than in any other species, which led to the great species of the late Cretaceous, such as Triceratops and probably Pentaceratops. They described and named him as Chasmosaurus marshaleni.
What does Chasmosaurus mean?
The name Chasmosaurus comes from the Greek chasma what does it mean opening, hole either fenestra. It is also combined with saurus What does it mean lizard.
In this way his name is translated as open lizard either lizard that opens, referring to the large openings of its steering wheel. The epithet beautifulwas assigned as a tribute to the fossil collector Walter Bell.
The subfamily Chasmosaurinae
The centrosaurus is located within the ceratopsids and within the Chasmosaurinae. It is a taxon or systematic group that differs from the Centrosaurinae by having horny and triangular shields.
They were quadrupeds with front legs shorter than the hind legs. His limbs were strong and his body was stocky. Its skull stood out for being massive and large, and ending in a pointed snout.
As was the case with ceratopsids, this horn was formed from the rostral bone that was located in the upper jaw and the predental bone originating in the lower jaw.
Their teeth were organized in batteries or rows that were continually replaced when they fell out as a result of wear.
They had a shorter nasal horn and longer eye horns compared to the Centroaurinae. The shield on its neck developed from the parietal and squamosal bones. It was 100% longer than the skull and had large openings.
The skulls of Pentaceratops and Torosaurus were almost two meters long, which are the longest known of any land animal.. The edge of the ruffles were simple protuberances and not spines as some Centrosaurinae used to have.
As with the Ceratopsidae, fossil remains of the Chasmosaurinae have only been found in North America. The west of the continent was part of Laramida Island during much of the Cretaceous.
It was isolated by a shallow sea, so ceratopsids remained confined to Laramidia. The known fossil remains of the group are only from the Upper Cretaceous and are between 80 and 65 million years old.
Some of the most famous specimens are: Agujaceratops, Anchiceratops, Arrinoceratops, Chasmosaurio, Coahuilaceratops, Eotriceratops, Kosmoceratops, Medusaceratops, Mojoceratops, Nedoceratops, Ojoceratops, Pentaceratops, Titanoceratops, Torosaurus, Triceratops, Utahceratops and Vagaceratops.
Chasmosaurus Characteristics
This dinosaur has an interesting fossil record. Specialists have managed to define what some of its characteristics could have been, which you can read below.
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Classification
In 1915, Lambe assigned the Chasmosaurus within the Ceratopsia and within this to the Chasmosaurinae. These were characterized by having long frills, while the Centrosaurinae had shorter ones. It had a basal position like Chasmosaurinae.
Feeding
It was a herbivorous dinosaur that made use of a hard, beak-shaped mouth with which it swallowed plant matter.. This was then chewed by teeth located on the sides of its mouth, something that only some ceratopsians could do.
Very possibly it consumed cycads, ferns and palm trees, among other great varieties of plants, existing in the forested areas it inhabited.
Locomotion
It moved on its four robust and powerful legs, making it a quadruped. There is still debate about how fast it moved. Some scientists think that they ran at the same speed as rhinos, which can reach 56 km/h.
It is very possible that they lived in herds, as was usual among ceratopsians. Bone beds of Chasmosaurus fossils have been found. This could indicate that they were grazing animals with a social disposition.
Living in herds would have helped them take care of the younger ones and protect themselves from predators.
Predators
There is a possibility that Chasmosaurus was preyed upon by Tyrannosaurus rex itself. Both coexisted in the final phase of the Cretaceous. His steering wheel could have been intimidating and deterrent to his attackers.
However, the youngest were possibly the most at risk from an attack. The adults would have been able to fight with their horns as modern rhinos do today, when threatened.
Where he lived
Chasmosaurus lived in North America, mostly in Canada. So that was hot and humid territory, very different from how we know it today. There were prehistoric tropical plants, such as palm trees and cycads.
When he lived
Analysis of the fossil remains of Chasmosaurus place it in the final phase of the Cretaceous, between 80 and 65 million years ago. It was the time during which most ceratopsids existed.
Habitat
Due to its characteristics, it is expected that Chasmosaurus lived in areas with grasslands, marshes, in semi-arid areas with water beds, where fruits suitable for its diet also grew.
The habitat in which Chasmosaurus lived during the Cretaceous period was marked by profound climatic changes that affected the entire surface of the planet. The slow spread of heat favored the development of certain types of plants, which now reproduced in a different way.
These changes promoted the development of spores, generally ferns, and naked seeds such as conifers that ensured the survival of certain species. Others, such as some kinds of tree ferns, giant horsetails and cycads, became extinct.
In the Cretaceous, plant species suddenly increased. This also happened thanks to the proliferation of insects and the increasingly warm climate. Bees in particular carried out the pollination process, giving rise to a greater number of plant species.
Some of these were predecessors of plants such as magnolias, figs and beeches that we know today.
Who did he live with?
It was a social animal that lived in small groups of a maximum of five dinosaurs and a minimum of three members. Sometimes they formed larger groups to migrate between territories in search of areas with more food.
Then they would get together in groups of 10 or 11 individuals. They were examples of grazing, something that has been proven when numerous beds with bones were discovered in the same areas.
Reproduction
It was oviparous and reproduced after a mating season. The females laid eggs that they cared for as a community, until they were beings with sufficient independence. The males also contributed to their upbringing.
Size
Specialists estimate that they could weigh between 2 and 3.5 tons.. An adult individual could measure between 5 and 6 meters long and 2.5 meters high.
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Behavior
Being a grazing animal, its level of aggressiveness was medium. It generally remained peaceful, but if provoked or attacked by a predator such as Tyrannosaurus rex it could unleash a powerful attack with its horns.
Life expectancy
The study of its fossil remains has allowed paleontologists to establish its natural development cycle. Therefore, they have managed to determine a life expectancy ranging from 37 to 74 years.
When did Chasmosaurus become extinct?
All fossil evidence indicates that Chasmosaurus existed until 66 million years ago….