Dino card No. 1129 of 2,027

Mamenchisaurus

Say it: mah-MEN-chih-SORE-us

Name means: “Mamenchi lizard”6

Ate: PlantsLong-necksMiddle Jurassic to Early Cretaceous

Mamenchisaurus was a giant plant-eater with the longest neck of any known animal. Its neck was so long that it could look into second-story windows without even trying!1

Lived

168 to 113 million years ago6

Middle Jurassic to Early Cretaceous

Fossils found in

China (Sichuan, Gansu, Yunnan), Mongolia, and Thailand6 2

Food

Plants6 1

Length

13 to 22 m2 1

M. constructus was about 13 m long, while M. hochuanensis reached 22 m

Weight

45 tonnes1

Height

3.5 m1

at the torso

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 torso

How heavy was it?

as heavy as 8 elephants

as long as 5 cars parked in a rowas long as 120 bananas end to endas heavy as 9000 watermelonsas tall as 2 doors stacked up

How big was Mamenchisaurus compared to YOU?

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cool stuff

Fun facts

Mamenchisaurus had 19 neck bones, more than any other dinosaur. Its neck was longer than its body and tail combined.1

The first Mamenchisaurus fossil was found near a ferry crossing on the Mamenchi River in Sichuan, China.2

Mamenchisaurus lived during the Late Jurassic and Early Cretaceous periods, about 168 to 113 million years ago.6

A complete skeleton of Mamenchisaurus hochuanensis was discovered in Hechuan County, Sichuan, and is the most complete sauropod ever found in China.1

Mamenchisaurus had a small head and spoon-shaped teeth, perfect for stripping leaves from branches.1

Some Mamenchisaurus fossils were found in red mudstone, which suggests they lived near rivers or lakes.1

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

?How big was Mamenchisaurus?

Most species were 15 to 26 metres (49 to 85 ft) long, possibly up to 35 metres (115 ft). It weighed about 12 tonnes (13 tons).3 4

?How long was its neck?

Its neck was up to 15 metres (49 ft) long, the longest of any known dinosaur. That is longer than a school bus.5 4

?What did Mamenchisaurus eat?

It was a plant-eater that ate conifers, ferns, cycads and other plants. It swallowed leaves whole and may have used stomach stones to help digest them.4

?When did Mamenchisaurus live?

It lived during the Late Jurassic Period, from about 161 to 145 million years ago. One species lived even later, in the Early Cretaceous.3 4

?Where was Mamenchisaurus found?

Fossils have been found in China, mostly in Sichuan and Xinjiang. The first one was discovered near the Mamenchi River in Sichuan.3 4

?Why did Mamenchisaurus have such a long neck?

The long neck probably helped it reach leaves high in trees or eat soft plants in wetlands without going into the water. It might also have been used for showing off to mates.4 5

?Was Mamenchisaurus bigger than T. rex?

Yes, Mamenchisaurus was much longer and heavier than T. rex. It could be up to 35 metres (115 ft) long, while T. rex was only about 12 metres (40 ft).3

?Did Mamenchisaurus have feathers?

No, Mamenchisaurus was a sauropod, and no sauropod fossils have ever been found with feathers. It had scaly skin like modern reptiles.3

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Myth buster

Myth: Many people think Mamenchisaurus used its long neck like a giraffe to reach high treetops.

Truth: Scientists think Mamenchisaurus probably kept its neck low and ate soft plants near the ground or in shallow water, because its neck bones were not very flexible.1

For dino experts

Scientific name: Mamenchisaurus
Named by: Young 19546
Group: Long-necks
Family / clade: Mamenchisauridae6
Classification: Sauropodomorpha > Sauropoda6
Age of the rocks: 168 to 113 million years (Bathonian / Aptian)6
Rock formations: Shaximiao, Ulan Malgait, Xiangtang6
Countries: China, Mongolia, Thailand6
Fossil records: 24 in the Paleobiology Database6
Discovery: Chinese paleontologist Yang Zhongjian (also known as C. C. Young) named Mamenchisaurus in 1954 based on a partial skeleton found near Yibin, Sichuan. The first complete skeleton of a larger species, M. hochuanensis, was dug up in Hechuan County in the 1970s.6 1
Still debated: Scientists still debate exactly how many species of Mamenchisaurus existed, because many fossils are incomplete and hard to compare.1

Where the facts come from

Mamenchisaurus (naturalhistory.si.edu)
PBDB Taxon (paleobiodb.org)
Mamenchisaurus (Wikipedia) (Wikipedia)
Mamenchisaurus - Dinosaur - Enchanted Learning Software (enchantedlearning.com)
Longest ever necked dinosaur discovered in China | Natural History Museum (nhm.ac.uk)
Mamenchisaurus in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.

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