Dino card No. 0635 of 2,027

Euoplocephalus

Say it: yoo-OP-loh-SEF-uh-lus

Name means: “well-armoured head”1

Ate: PlantsArmoured dinosLate Cretaceous

Euoplocephalus was a tank-like dinosaur covered in bony armour and a heavy club on its tail. It lived in what is now Canada and the USA during the Late Cretaceous period. This slow-moving plant-eater could defend itself from big predators like Albertosaurus.1

Lived

84 to 66 million years ago4

Late Cretaceous

Fossils found in

Alberta, Canada and Montana, USA1 2

Food

Plants1

Length

5.3 m1

Weight

2 tonnes1

Height

1.2 m1

at the hips (torso height)

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

How long was it?

How tall was it?

at the hips (torso height)

How heavy was it?

as heavy as 1.5 cars

as long as 5 dogs nose to tailas long as 29 bananas end to endas heavy as 67 big dogsas heavy as 400 watermelonsup to the handle of a door

How big was Euoplocephalus compared to YOU?

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cool stuff

Fun facts

Euoplocephalus had a heavy club at the end of its tail made of bone. It could swing this club to fight off predators.1

Its body was covered in rows of bony plates called scutes. It also had two bone rings around its neck for extra protection.1

Euoplocephalus was about 5.3 metres (17 feet) long and weighed around 2 metric tons (2.2 short tons). That is as heavy as a small car.1

The first fossil was found in 1897 in Alberta, Canada. It was originally named Stereocephalus, but that name was already used for an insect, so it was changed to Euoplocephalus in 1910.1

Euoplocephalus lived between about 76 and 75 million years ago, during the late Campanian stage of the Late Cretaceous.1

Scientists once thought many different ankylosaur fossils all belonged to Euoplocephalus, but now they know most are separate species like Scolosaurus and Platypelta.1

Euoplocephalus had a short, drooping snout and a horny beak to bite off plants. Its teeth show it could chew tough plant material.1

AI-made picture of Euoplocephalus — An AI-made picture of how Euoplocephalus might have looked, made by a computer from what scientists know. It is a guess: the real animal may have looked different, and nobody knows its true colours.

you asked

Most asked questions about Euoplocephalus

?How big was Euoplocephalus?

About 5.3 metres (17 feet) long and 2 tonnes (2.2 short tons) in weight, as heavy as a small car.1 3

?What did Euoplocephalus eat?

It was a plant-eater. It used a horny beak to bite off plants and had small teeth to chew tough plant material.1 3

?Did Euoplocephalus have a tail club?

Yes, it had a heavy bony club at the end of its tail. It could swing this club to defend itself from predators like Albertosaurus.1 3

?Was Euoplocephalus bigger than Ankylosaurus?

No, Ankylosaurus was bigger. Among ankylosaurids, Euoplocephalus was exceeded in size only by Ankylosaurus and perhaps Tarchia and Cedarpelta.1

?When did Euoplocephalus live?

It lived during the Late Cretaceous period, about 76 to 70 million years ago.3

?Where was Euoplocephalus found?

Fossils have been found in Canada (Alberta) and the United States (Montana).1 3

?How fast could Euoplocephalus run?

Nobody knows for sure, but it was a slow-moving dinosaur with short, sturdy legs built for walking, not running.1

?What does the name Euoplocephalus mean?

It means 'well-armed head', from Greek words for 'well', 'armed', and 'head'.1

Ask Rex about Euoplocephalus

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Myth buster

Myth: Euoplocephalus could roll into a ball like an armadillo to protect itself.

Truth: Euoplocephalus could not roll into a ball. It relied on its armour and tail club for defence.1

For dino experts

Scientific name: Euoplocephalus
Named by: Lambe 19104
Group: Armoured dinos
Family / clade: Ankylosauridae4
Classification: Ornithischia > Ankylosauria > Ankylosauridae > Thyreophora4
Age of the rocks: 84 to 66 million years (Campanian / Maastrichtian)4
Rock formations: Dinosaur Park, Judith River, Two Medicine4
Countries: Canada, USA, China4
Fossil records: 18 in the Paleobiology Database4
Also known as: Stereocephalus (older names now counted as the same animal)4
Discovery: Canadian paleontologist Lawrence Morris Lambe discovered the first Euoplocephalus fossil on 18 August 1897 in what is now Dinosaur Provincial Park, Alberta. He named it Stereocephalus in 1902, but changed the name to Euoplocephalus in 1910 because the old name was already taken.1
Still debated: Scientists still debate exactly which fossils belong to Euoplocephalus and which belong to other closely related ankylosaurs like Anodontosaurus and Scolosaurus.1

Where the facts come from

Euoplocephalus (en.wikipedia.org)
PBDB Taxon (paleobiodb.org)
Euoplocephalus | Natural History Museum (nhm.ac.uk)
Euoplocephalus in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.

Every fact on this page has a number that points to its source. If we got something wrong, sorry, we are dino fans, not a science journal. Tell us at [email protected] and we will fix it.

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