Dino card No. 0022 of 2,027

Actiosaurus

Say it: AK-tee-oh-SORE-us

Name means: “coast lizard”1

Ate: PlantsLong-necksLate Triassic

Actiosaurus was a reptile that lived a very long time ago, during the Late Triassic period. Scientists are not sure exactly what kind of reptile it was, but it might have been a dinosaur or something else!1 2

Lived

206 to 201 million years ago3

Late Triassic

Fossils found in

France, specifically from the Antully bonebed near Autun.1 2

Food

Plants2

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

cool stuff

Fun facts

Actiosaurus was first described in 1883 by a scientist named Henri Sauvage.1

It was originally thought to be a dinosaur, but in 1908 scientists thought it might be an ichthyosaur, which is a marine reptile, not a dinosaur.1

Some scientists now think Actiosaurus might be a choristodere, which is another kind of reptile that lived in water.1

Actiosaurus is considered a nomen dubium, which means its fossils are too incomplete to be sure what it really is.1

The fossils of Actiosaurus are about 205 to 201 million years old, from the Rhaetian age of the Late Triassic.2

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

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Myth buster

Myth: Actiosaurus was a long-necked sauropod dinosaur.

Truth: Scientists are not sure what Actiosaurus was. It might be a dinosaur, but it could also be a marine reptile like an ichthyosaur or a choristodere. Its fossils are too incomplete to know for sure.1

For dino experts

Scientific name: Actiosaurus
Named by: Sauvage 18833
Group: Long-necks
Family / clade: Anchisauridae3
Classification: Sauropodomorpha3
Age of the rocks: 206 to 201 million years (Rhaetian)3
Countries: France3
Fossil records: 1 in the Paleobiology Database3
Discovery: Actiosaurus was named by Henri Sauvage in 1883 from fossils found in the Antully bonebed near Autun, France.1
Still debated: Scientists still debate whether Actiosaurus was a dinosaur, an ichthyosaur, or a choristodere, because the fossils are so incomplete.1

Where the facts come from

Actiosaurus (en.wikipedia.org)
PBDB Taxon (paleobiodb.org)
Actiosaurus 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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