The Animantarx is one of the most interesting genera of ankylosaurid dinosaurs as it is the very first dinosaur to be discovered with the help of technology.
Ramal Jones, a radiologist, found its fossils while performing a radiological survey in the Mussentuchit Member of the Cedar Mountain Formation in Utah as some places in the area had shown radioactivity.
His scintillometer picked up a higher level of radioactivity than usual at a certain area, and when the area was excavated, the remains of a dinosaur were found.
Later, these remains were described and named by K. Carpenter, J. I. Kirkland, D. L. Burge, and J. Bird in 1999.
The fact that they were found in the Mussentuchit Member of the Cedar Mountain Formation implied that these animals would have lived almost 104-98 million years ago during the Late Cretaceous period.
They consisted of fossils of a skeleton of a single specimen, including its lower jaw, back half of the skull, some parts of its limbs, as well as its neck and back vertebrae.
Its skull was found to be domed, and its jaw was armored along half of its length, which led to scientists coming to the conclusion that its whole body was armored and covered in bony plates of armor as well, but a tail club was not present.
There was also evidence that it had small horns on the top and sides of its skull.
These fossils were studied carefully, given their radioactivity, and are currently preserved and exhibited in the College of Eastern Utah, Prehistoric Museum, which is located in Price, Utah.
If you want to learn more about this cool prehistoric animal, then keep reading!
Animantarx is certainly a very dashing name that has a very simple pronunciation. It can be pronounced as 'ænɪˈmæntɑːrks' and its phonetic pronunciation is 'An-e-man-tarks'.
What type of dinosaur was an Animantarx?
An Animantarx belonged to the order Ornithischia. It has been put in the family Nodosauridae, within the suborder Ankylosauria.
Nodosaurid ankylosaurs were heavy-bodied animals that were usually covered in rows of bony armored plates but did not have a tail club at the end of their tails like most ankylosaurs. Some also had spikes or spines covering their necks and backs.
When the fossils of the Animantarx were studied, it was found that the animal could have been related to Edmontonia, which also belongs to Nodosauridae, and lived during the Late Cretaceous period.
In which geological period did the Animantarx roam the Earth?
The Animantarx was found in the Mussentuchit Member of the Cedar Mountain Formation. All fossils found within this member are known to have existed from the Albian age of the Early Cretaceous to the Cenomanian age of the Late Cretaceous. They would have lived on Earth almost 104-98 million years ago.
When did the Animantarx become extinct?
Since it lived during the last epoch of the Cretaceous, it is safe to say that this ankylosaur would have been a victim of the Cretaceous-Paleogene extinction event which occurred around 66 million years ago.
This event was caused by the impact of a giant comet or asteroid on the surface of the Earth and led to the extinction of almost all species of plants and animals living at the time.
Where did an Animantarx live?
This prehistoric animal would have lived in what now constitutes North America, as its remains were found in the Cedar Mountain Formation which is located in the US state of Utah. Since being discovered, its fossil remains have been placed and exhibited in the College of Eastern Utah, Prehistoric Museum, located in Price, Utah.
What was an Animantarx's habitat?
The bones of this dinosaur were found in mudstone, and fossils of a lot of aquatic animals were also discovered in the same Formation in Utah, which could mean that the land where these animals all lived could have been a floodplain.
However, there is also the possibility that it could have been a grassland or a forest habitat where there were plenty of water bodies.
Who did an Animantarx live with?
Ankylosaurs are usually known for being social animals and could have lived in small groups or herds.
From the bones of other dinosaurs found in the same site as the Animantarx, it can also be thought that it coexisted with dinosaurs from other genera, such as the iguanodont Eolambia, and the ankylosaurs Gastonia and Cedarpelta, and could have even been related to them.
It was also once thought that the bones of a dinosaur found in the Cedar Mountain Formation belonged to the Sauropelta, but that theory has since been disproved.
How long did an Animantarx live?
Though the lifespan of an Animantarx is not known, life expectancies of other ankylosaurs have been estimated to be in the range of 60-80 years.
How did they reproduce?
Ankylosaurs were oviparous, meaning they did not give birth to live young, but laid eggs from which their young ones emerged.
Animantarx Fun Facts
What did an Animantarx look like?
The appearance of an Animantarx ramaljonesi is thought to have been similar to other ankylosaurs. It had a bulky and short body.
Its skull was found to be domed with a pattern of armor covering its roof. Small horns were also present on the top and sides of its skull.
The structure of its neck vertebrae and back vertebrae classified this dinosaur as a nodosaurid. Its tail, although long, lacked the tail club that is present in a dinosaur belonging to Ankylosauria, but absent in the tail of a nodosaurid.
Bone fragments were also found from all its limbs, which were found to be of equal length. Its lower jaw was also armored along half of its length, and its entire upper body would have been covered with bony armor plates like the lower jaw or with spikes to protect itself from predators.
How many bones did a have?
The exact number of bones in the body of an Animantarx is not currently known as a complete skeleton of the animal is yet to be found.
How did they communicate?
It is not known how exactly these dinosaurs communicated but they could have used vocalizations or their body language or a combination of both to express themselves all those million years ago.
How big was an Animantarx?
The body length of the Animantarx has been estimated to have been around 10 ft (3 m). It would have been just a little smaller in length than a Gastonia, which was also found around the same time in Utah, and is thought to be related to the Animantarx.
How fast could an Animantarx move?
Ankylosaurs are thought to have been very slow and their speed would not have exceeded 6.2 mph (10 kph).
How much did an Animantarx weigh?
This dinosaur is estimated to have been weighed in the range of 1,100-1,540 lb (500-700 kg).
What were the male and female names of the species?
There were no special names for male and female dinosaurs of this species or genus.
What would you call a baby Animantarx?
A baby Animantarx would have been called a hatchling.
What did they eat?
Like other members of Ornithischia, this dinosaur was also herbivorous and would have fed on low-lying plants and vegetation.
Some predators that could have fed on an Animantarx ramaljonesi in the Cretaceous could have been the theropod Deinonychus, as it was also found in the Cedar Mountain Formation in Utah.
How aggressive were they?
These dinosaurs would not have been very aggressive as they were herbivores, and the armor on its body would have only been used for defense purposes.
Did you know...
Around the time when the fossils of Animantarx were discovered by Ramal Jones, he and his wife, Carol Jones also discovered the bones of another dinosaur nearby, within the Cedar Mountain Formation in Utah.
These bones were then found to belong to the iguanodont Eolambia, and its type species, Eolambia caroljonesa, was named after Carol Jones, who discovered its fossils.
What dinosaur has no tail?
All dinosaur fossils that have been discovered show that they had tails, though their lengths might vary. Some herbivores such as the ankylosaurids even had a mace-like club at the end of their tails that would have been used to protect themselves against a predator.
However, the dinosaurs belonging to the family Nodosauridae within Ankylosauria did not have tail clubs. The reason for this is currently unknown.
What does the term Animantarx mean?
After it was found by Ramal Jones, the name Animantarx was given to this dinosaur in 1999 by K. Carpenter, J. I. Kirkland, D. L. Burge, and J. Bird, because of a comment that R. S. Lull made about the armor of these animals.
He said that the armored body of an Animantarx was like a living fortress or citadel that would have been very hard to attack.
The name is derived from Latin meaning 'alive' and 'citadel or fortress', and translates from Latin to 'living fortress'.
The species name, Animantarx ramaljonesi, is named after Ramal Jones, who originally discovered the bone fossils of this prehistoric animal. These bones are now preserved in the College of Eastern Utah, Prehistoric Museum in Price, Utah.
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 Archaeoceratops facts and Geranosaurus facts for kids.
You can even occupy yourself at home by coloring in one of our free printable Animantarx coloring pages.
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Second image by Conty
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