Dino card No. 0398 of 2,015

Chensaurus

Say it: chen-SORE-us

Ate: MeatIchthyosaursEarly Triassic to Middle TriassicNot technically a dinosaur

Chensaurus was an early ichthyosaur, a marine reptile that swam in the seas during the Triassic Period. It had a long, narrow body and a small tail fin, and it moved through the water like an eel. It was not a dinosaur, but a distant relative of lizards and snakes.1

Fun fact: this sea reptile swam while dinosaurs walked on land. Everyone calls them dinos, but they were a different branch of reptiles.

Lived

251 to 237 million years ago3

Early Triassic to Middle Triassic

Fossils found in

Fossils of Chensaurus were found in Anhui Province, China.3

Food

Meat3

Length

up to 1 m2

small body size of less than 1 m

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

cool stuff

Fun facts

Chensaurus is one of the oldest known ichthyosaurs, living about 250 million years ago.3

It had a long, narrow body and a small caudal fin, which suggests it swam like an eel, not like a fish.1

Chensaurus had a high number of vertebrae in its body, which helped it move in a wavy, eel-like way.1

It is considered an evolutionary intermediate between land reptiles and later, more fish-like ichthyosaurs.1

The name Chensaurus was given in 1991, but some scientists think it is the same as another ichthyosaur called Chaohusaurus.2

AI-made picture of Chensaurus — An AI-made picture of how Chensaurus 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.

Myth buster

Myth: Chensaurus was a dinosaur.

Truth: Chensaurus was an ichthyosaur, a marine reptile, not a dinosaur. Ichthyosaurs lived in the sea and were more closely related to lizards and snakes.1

For dino experts

Scientific name: Chensaurus
Named by: Mazin Suteethora et al. 19913
Group: Ichthyosaurs
Family / clade: Grippiidae3
Classification: Ichthyosauria > Ichthyosauromorpha3
Age of the rocks: 251 to 237 million years ()3
Countries: China3
Fossil records: 9 in the Paleobiology Database3
Discovery: Chensaurus was named by Mazin Suteethora and colleagues in 1991. The fossils were found in Anhui Province, China.3 3
Still debated: Scientists debate whether Chensaurus is a separate genus or just a younger name for Chaohusaurus, because the fossils are very similar.2

Where the facts come from

Eel-like swimming in the earliest ichthyosaurs - ADS (ui.adsabs.harvard.edu)
PBDB Taxon (paleobiodb.org)
Chensaurus 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.