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Euoplocephalus

'Well-armoured head'

WWD

Euoplocephalus was a strange-looking dinosaur: almost turtle-like in appearance, with spiny body armour and a clubbed tail. Euoplocephalus would have been one of the most armoured dinos ever. Its head alone had bony eyelids that came down like shutters, a cobblestone-like bony forehead, and pyramid-shaped horns jutting from the back of the head.

They call it home

Euoplocephalus has been found in Dinosaur Park and Horseshoe Canyon formations of Alberta, Canada and the Judith River Formation of Montana. These stretches of ancient rock have been preserved for 80 million years. Euoplocephalus would have lived alongside Stegoceras, Albertosaurus and many others.

What we heard about their hearing

What we heard about their hearing

Euoplocephalus was able to hear low frequency sounds, the same kind of sounds it could have produced itself.


What big teeth you have

What big teeth you have

Don't let the feeble teeth of Euoplocephalus fool you. It was an eating machine with deep cheek pouches, and a secondary palate so that it could chew and breathe at the same time.

Nose knowledge

Nose knowledge

This dinosaur really smelled! It had an extensive and complex respiratory passage, which may have meant that its sense of smell was outstanding.


The poop scoop

The poop scoop

Euoplocephalus left us very little about its leavings, but since they had a very high-fibre diet, it would be safe to say it would have produced mountains of dung.

The most fantastic find

The most fantastic find

Euoplocephalus is the best known ankylosaur. Palaeontologists have recovered over forty individual fossils consisting of over fifteen known skulls, as well as a few almost-complete specimens with armour plating still attached. The discoveries with armour plating still attached are the most fascinating because it allows scientists to see exactly how the animal would have looked in real life.

Euoplocephalus features

Euoplocephalus features Height: 2m (6.56ft)
Length: 6m (19.68ft)
Weight: 2 tonnes (2.24 short tons)
Top speed: 8kph (4.97mph)
Vision: Euoplocephalus would have needed a pair of prehistoric glasses, since it had small eyes and most probably weak vision.
Skin: Euoplocephalus' body was covered in bands of plates running down like pavements covering its entire body.
Brain: Euoplocephalus shares the distinction of being a bit of a dunce like the tiny-brained Stegosaurus. The brain of Euoplocephalus could sit nicely inside a coffee cup.
Prey: Euoplocephalus probably ate low-growing plants like small ferns, cycads and perhaps even flowering plants, which first evolved in the Cretaceous. Euoplocephalus had a stomach like a fermentation vat, which would help decompose even the toughest plants. To accommodate such an enormous digestive machine, the ribcage was deep and the abdomen was built like a barrel.
Bite: Euoplocephalus were vegetarians, probably eating the equivalent of over 700 carrots per day.
Nest: We can guess from other similar dinosaurs that Euoplocephalus laid eggs much like our modern turtles and they would have deposited 20-30 rounded eggs in a heap.

Euoplocephalus facts and theories

Euoplocephalus facts and theories

  1. Euoplocephalus had an unusual and unique active form of defence. If a predator, such as a tyrannosaur persisted, Euoplocephalus would swing its club-like tail from side to side, causing serious injury.
  2. No wonder the animal's name means 'well-armoured head'. Its skull was so thick that even a raptor like Deinonychuscould would leave barely a scratch.
  3. Euoplocephalus habitat was vast floodplains bordering ancient rivers.
  4. Originally this dinosaur was given the name Stereocephalus, but it was later discovered that other scientists had used this name to refer to a new species of insect. It is a rule among scientists that each formal name of an animal can only be used once, which meant that Stereocephalus became Euoplocephalus.
  5. Most animals have a quite simple nasal passageway in which the nostrils are linked to the throat by a short passage. Ankylosaurs have a highly convoluted nasal passageway that twists round and round like a loopy strand of spaghetti. What was the purpose of this strange shape? Maybe the looping condition helped ankylosaurs smell, breathe, regulate body temperature better, or make melodic sounds.
  6. Some scientists think that Euoplocephalus could even use their front legs to dig for tubers in the ground, like some mammals do today.