Dino card No. 1221 of 2,027

Mussaurus

Say it: muh-SORE-us

Name means: “mouse lizard”1

Ate: PlantsLong-necksEarly Jurassic

Mussaurus was a long-necked dinosaur that lived in what is now Argentina. When it hatched, it was tiny, about the size of a mouse, but adults grew as long as a school bus!1

Lived

200 to 193 million years ago6

Early Jurassic

Fossils found in

Laguna Colorada Formation, Santa Cruz province, Patagonia, Argentina2 1

Food

Plants2 1

Length

0.2 to 8 m1 3

infants about 20 cm, adults up to 8 m

Weight

0.053 kg to 1.6 tonnes1

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

How long was it?

How heavy was it?

as heavy as 1 cars

as long as 8 dogs nose to tailas long as 44 bananas end to endas heavy as 53 big dogsas heavy as 320 watermelons

How big was Mussaurus compared to YOU?

Just maths in your browser. Nothing is saved or sent anywhere.

cool stuff

Fun facts

Mussaurus babies were only 20 cm (7.9 in) long and weighed about as much as a chicken egg.1 3

As it grew, Mussaurus changed from walking on all fours to walking on two legs.1

Scientists found over 100 eggs and 80 skeletons of Mussaurus together, showing they lived in herds.1

This dinosaur lived about 193 million years ago, during the Early Jurassic period.2

Adult Mussaurus could reach 8 metres (26 ft) long and weigh up to 1.6 metric tons (1.8 short tons).1

Mussaurus is one of the earliest dinosaurs known to have complex social behavior, like living in groups.1

AI-made picture of Mussaurus — An AI-made picture of how Mussaurus 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 Mussaurus

?What did Mussaurus eat?

Mussaurus was an herbivore, meaning it ate plants. It had a long neck to reach leaves and ferns.1

?How big was a baby Mussaurus?

Baby Mussaurus were tiny, about 20 centimetres long and weighing as little as a chicken egg, around 53 to 77 grams.1

?Did Mussaurus live in herds?

Yes, Mussaurus is the earliest dinosaur known to have lived in herds. Scientists found over 100 eggs and 80 skeletons together, showing they lived in age-segregated groups.1 4 5

?How fast could Mussaurus run?

Nobody knows for sure, but since adults walked on two legs and were medium-sized, they could probably move at a moderate jogging speed.1

?When did Mussaurus live?

Mussaurus lived about 193 million years ago, during the Early Jurassic period.1 5

?Why is it called Mussaurus?

Mussaurus means 'mouse lizard' because the first fossils found were tiny babies, about the size of a mouse.1

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Myth buster

Myth: Mussaurus was always a tiny dinosaur.

Truth: Only the babies were tiny. Adults grew to be huge, up to 8 metres long.1

For dino experts

Scientific name: Mussaurus
Named by: Bonaparte and Vince 19796
Group: Long-necks
Family / clade: Sauropodiformes6
Classification: Sauropodomorpha6
Age of the rocks: 200 to 193 million years (Sinemurian)6
Rock formations: Laguna Colorada6
Countries: Argentina6
Fossil records: 2 in the Paleobiology Database6
Discovery: Mussaurus was named by Jose Bonaparte and Martin Vince in 1979. They found tiny skeletons and eggs in the Laguna Colorada Formation in Argentina.2 3
Still debated: Scientists are still debating whether Mussaurus is a direct ancestor of the giant sauropods.1

Where the facts come from

Mussaurus (en.wikipedia.org)
PBDB Taxon (paleobiodb.org)
A M E G H I N I A N A (naturalhistory.si.edu)
Earliest evidence of herd-living and age segregation amongst dinosaurs | Scientific Reports (nature.com)
Fossil bonanza reveals earliest evidence of dinosaurs living in herds | National Geographic (nationalgeographic.com)
Mussaurus 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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