The term Coelosaurus antiquus means the antique hollow lizard. This species is a dubious Theropod species and was named by Joseph Leidy in the year 1865. Leidy also described the species.
The fossil specimens were found in the Navesink Formation of New Jersey and the only remains that were found were two tibiae. It lived during the Late Cretaceous age. The fossil remains found are preserved in the American Museum of Natural History.
The Leidy found species was later classified under Ornithomimus by paleontologists Donald Baird and John R. Horner as Ornithomimus antiquus in the year 1979.
Some other Paleontologists as well followed up on this classification, but many have not accepted this as there is no justification whatsoever for the classification of the New Jersey species to be classified under a genus that is well known to be only from North America.
David Weishampel in 2004, after researching on the specimens declared that he thought the Coelosaurus antiquus to be indeterminate among the Ornithomimosaurs and declared it to be a nomen dubium. Paleontologists Bard and Horner in 1979, discovered the name Coelosaurus was already occupied by another dubious taxon and was named by an anonymous author called Richard Owen in 1854.
Scroll down to read about the Coelosaurus antiquus's life, what they fed on, their habits, and other exciting details! And for more relevant content, read our Caviramus factsand Tupuxuara facts for kids.
Coelosaurus Interesting Facts
How do you pronounce 'Coelosaurus'?
The dinosaur name Coelosaurus can be pronounced as Seel-o-saw-rus. As the word is in English with Greek roots, Coel is pronounced as Seel or Sill.
What type of dinosaur was a Coelosaurus?
The Coelosaurus antiquus is a meat-eating reptilia class dinosaur and this dinosaur species is a dubious Theropod dinosaur and was named by Joseph Leidy in the year 1865. The fossils were found in the Navesink Formation of New Jersey and the only remains that were found were two tibiae. It lived during the Late Cretaceous period.
In which geological period did the Coelosaurus roam the earth?
These dinosaurs lived during the Late Cretaceous period which was about 94-86 million years ago. They were alive during the Late Jurassic period in history as well.
When did the Coelosaurus become extinct?
Dinosaurs, in general, went extinct almost 65 million years ago, that is, at the end of the Cretaceous period, after living on the earth for about 165 million years. But this species existed in the Late Cretaceous period which was 94-86 million years ago. They also walked the Earth during the Late Jurassic period in history.
Where did a Coelosaurus live?
The Unenlagia dinosaur-bird existed in the Late cretaceous period and fed on herbivorous dinosaurs which means they habituated areas that were near nature. Terrestrial habitats with moderate temperature and dense vegetation were the perfect places for the bird-like dinosaur to inhabit.
During the Late Cretaceous period, areas of North America had started to drift away from Europe and South America and were just connected to Asia which led it to have several large islands by warm, shallow seas.
What was a Coelosaurus' habitat?
These dinosaurs inhabited areas of North America and the fossils of the dinosaur were found in the Navesink Formation of New Jersey.
Who did a Coelosaurus live with?
There is no information as of now on whether these theropod bird species stayed in groups or they stayed alone. But if assumed, small dinosaurs like this tend to stay in flocks in order to protect themselves from predators and also to hunt easily.
How long did a Coelosaurus live?
These theropod dinosaurs are still a species that hasn't been discovered fully and therefore the age of their survival is unclear. Till more fossil remains are unearthed, nothing can be speculated or proven.
How did they reproduce?
Theropods much like other reptiles mated with each other during the breeding season and in the case of this breed, the female dinosaur laid eggs. The eggs hatch after a certain period of time and newborn dinosaurs came out.
The adult dinosaur birds took care of the newborns till they could move with their parents or go along with their new family.
Coelosaurus Fun Facts
What did a Coelosaurus look like?
The only fossil to be found was two tibiae during excavations and this doesn't help in any way to structure how the hollow lizard skeleton looked, but according to Donald Baird and John R. Horner as this dinosaur was classified under the Ornithomimus genus, and therefore if the Ornithomumus is observed, the features of this dinosaur can be assumed.
The Coelosaurus like the Ornithomimus was bipedal and had long slender forearms and a long neck with a bird-like, elongated, and toothless beak skull structure. They had very long limbs, hollow bone structures, and large brains and eyes.
The skull was quite big and they presumably had bigger brains in comparison to other non-avialan dinosaurs, but this doesn't prove that they had more intelligence.
The feet bone structure resembled that of a sloth and therefore researchers assumed that they could hang from trees while preying or ideally by using their feet to clench on branches.
The tail of this dinosaur species might have been long and rigid, unlike sauropods who had whip-like tails. They had smaller teeth at the back of the beak which helped them to bite into their prey.
*We've been unable to source an image of a Coelosaurus and have used an image of a Triceratops instead. If you are able to provide us with a royalty-free image of a Coelosaurus, we would be happy to credit you. Please contact us at hello@kidadl.com
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How many bones did a Coelosaurus have?
There is no fossil specimen on the skeleton of this species as of now indicating the number of bones these theropod dinosaurs have. Until more specimen is discovered paleontologists nothing can be assumed.
How did they communicate?
There is no specific mention on how they communicated as it is quite difficult to find, but they definitely didn't have modern means of communication. Like any other animal, dinosaurs also communicated by making sounds and using their body language.
These birds might have included hoots and hollers to communicate as well. Having wings it was natural for the dinosaurs to fly and they could use their wings to make a flapping sound in order to communicate.
How big was a Coelosaurus?
The Coelosaurus was about 110 in (2.8 m) in length and this makes it about five times smaller in length than the prairie falcon which is about 13-18 in (33-45.7 cm) in length.
How fast could a Coelosaurus move?
This Ornithomimus genus dinosaur was a swift flyer and had the ability to fly at a great speed due to its bone structure. The actual speed can't be mentioned as this is speculation made based on the genus of the Coelosaurus.
How much did a Coelosaurus weigh?
The weight of this dinosaur species was about 132.3 lb (60 kg). This makes it about two to four times lighter than the ostrich which weighs about 138-308 lb (62.6-139.7 kg).
What were the male and female names of the species?
There is no specific name for the male or female dinosaurs of this species and are commonly known as Coelosaurus, Coelosaurus antiquus, or hollow lizard. Search for the rest of the fossils is still going on and only after the complete discovery of the significant fossils can it be differentiated.
What would you call a baby Coelosaurus?
The newborn dinosaur was known as hatchling or nestling. This was common for most dinosaur species. There is no specific information on the names of newborns for this dinosaur-bird as of now due to the lack of fossil remains.
What did they eat?
These flying dinosaur species was a carnivore and therefore fed on the meat of the herbivorous dinosaurs smaller in size. They had smaller teeth at the back of the beak which helped them to bite into their prey.
How aggressive were they?
Based on research, dinosaurs are divided into two groups where the sauropods are herbivores and don't attack each other or other dinosaurs while the theropods were meat-eaters and attacked each other and the other dinosaurs as well.
Did you know...
Even though these theropods were meat-eaters they were quite small in size, and might not have been as aggressive as other dinosaur birds like the Ornithomimus velox.
What does the name Coelosaurus mean?
The term Coelosaurus antiquus means the antique hollow lizard. This species was named by Joseph Leidy in the year 1865.
How did Coelosaurus go extinct?
Dinosaurs, in general, went extinct almost 65 million years ago, that is, at the end of the Cretaceous period, after living on the earth for about 165 million years. As history explains an asteroid crashed on the surface of the earth due to which there was destruction and the dinosaurs became extinct.
With different changing periods though, dinosaurs might have gone extinct or just evolved into a different species like the Archaeopteryx.
Here at Kidadl, we have carefully created lots of interesting family-friendly dinosaur facts for everyone to discover! For more relatable facts, check out these Utahraptor fun facts, or Yunnanosaurus facts for kids.
*We've been unable to source an image of a Coelosaurus and have used an image of a Triceratops instead. If you are able to provide us with a royalty-free image of a Coelosaurus, we would be happy to credit you. Please contact us at hello@kidadl.com.
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