Dino card No. 1136 of 2,027

Maraapunisaurus

Say it: mah-RAH-poo-nee-SORE-us

Name means: “huge reptile”1

Ate: PlantsLong-necksLate Jurassic to Early Cretaceous

Maraapunisaurus was a giant, long-necked plant-eater that lived in what is now Colorado, USA. It is known from just one huge backbone bone that was lost long ago, so scientists have to study old drawings to figure out how big it really was.1 2

Lived

149 to 143 million years ago3

Late Jurassic to Early Cretaceous

Fossils found in

Garden Park, north of Cañon City, Colorado, USA1

Food

Plants1 3

Length

30.3 to 32 m2 1

estimate based on a rebbachisaurid model

Weight

70 tonnes to 120 tonnes1 2

estimates vary; 70 t (Molina-Pérez & Larramendi 2020) to 80, 120 t (Paul 2019)

Height

7.95 m1

at the hips

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

How heavy was it?

as heavy as 20 elephants

as long as 7 cars parked in a rowas long as 180 bananas end to endas heavy as 24000 watermelonstaller than a giraffe

How big was Maraapunisaurus compared to YOU?

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cool stuff

Fun facts

Maraapunisaurus is only known from a single fossil bone, a huge backbone spine that was 1.5 meters (4.9 feet) tall when found.1 2

The original fossil was lost after being studied in the 1870s, so all we have are old drawings and notes.1

Scientists used to think Maraapunisaurus was the longest dinosaur ever, at 58 meters (190 feet), but newer studies say it was about 30 to 32 meters (98 to 105 feet) long.1 2

It belongs to a group called rebbachisaurids, which are relatives of Diplodocus with strange, air-filled bones in their spines.1 2

The name Maraapunisaurus comes from the Southern Ute word 'maraapuni' meaning 'huge', because of its enormous size.1

Maraapunisaurus lived in a savanna-like environment with ferns and some tall trees along rivers, which it used for shade.1

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

?Was Maraapunisaurus the biggest dinosaur ever?

Some scientists used to think so, but newer estimates say it was about 35 to 40 metres long, making it one of the longest known vertebrates ever, though its exact size compared to others like Supersaurus is uncertain.1

?How long was Maraapunisaurus?

Estimates vary: the largest guess was 58 metres, but most modern studies say 30 to 40 metres.1 2

?How much did Maraapunisaurus weigh?

Scientists estimate its mass at 70 to 120 tonnes.1

?What did Maraapunisaurus eat?

It was a plant-eater that probably ate ferns and other low plants in a savanna-like environment, with some tall trees along rivers for shade.1

?When did Maraapunisaurus live?

It lived during the Late Jurassic period, about 150 million years ago.1

?Where was Maraapunisaurus found?

Its only known fossil was discovered in Garden Park, near Cañon City, Colorado, USA.1

?Why is Maraapunisaurus only known from one bone?

The single backbone bone was lost after being studied in the 1870s, so scientists now rely on old drawings and notes.1

?Is Maraapunisaurus a dinosaur?

Yes, it is a sauropod dinosaur, a long-necked plant-eater from the group called rebbachisaurids.1

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Myth buster

Myth: Many people think Maraapunisaurus was the biggest dinosaur ever, longer than a blue whale.

Truth: Newer research shows it was about 30 to 32 meters long, still huge but not the biggest. The old huge size estimate was based on a mistaken classification as a diplodocid.1 2

For dino experts

Scientific name: Maraapunisaurus
Named by: Carpenter 20183
Group: Long-necks
Family / clade: Rebbachisauridae3
Classification: Sauropodomorpha > Sauropoda > Diplodocoidea3
Age of the rocks: 149 to 143 million years (Tithonian)3
Rock formations: Morrison3
Countries: USA3
Fossil records: 1 in the Paleobiology Database3
Discovery: The only fossil was found in 1877 by Oramel Lucas near Cañon City, Colorado, and sent to paleontologist Edward Drinker Cope. Cope named it Amphicoelias fragillimus in 1878. In 2018, Kenneth Carpenter renamed it Maraapunisaurus after realizing it was a different kind of dinosaur.1 2
Still debated: Scientists are still not sure exactly how big Maraapunisaurus was because the only fossil is lost and the drawings may not be perfectly accurate.1

Where the facts come from

Maraapunisaurus (en.wikipedia.org)
Maraapunisaurus fragillimus, N.G. (formerly Amphicoelias fragillimus), a basal Rebbachisaurid from the Morrison Formation (Upper Jurassic) of Colorado | Geology of the Intermountain West (giw.utahgeology.org)
Maraapunisaurus in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.

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