Simosaurus

Say it: sy-mo-SORE-us

Name means: “snouted lizard”1

Ate: MeatOther sea reptilesMiddle Triassic to Late TriassicNot technically a dinosaur

Simosaurus was a marine reptile that swam in warm, shallow seas during the Middle Triassic, about 240 to 230 million years ago. It had a blunt, flattened head and blunt teeth for crushing hard-shelled prey like clams and ammonites.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

247 to 201 million years ago2

Middle Triassic to Late Triassic

Fossils found in

France and Germany, with additional fossils from Italy, Israel, and Saudi Arabia1 2

Food

Meat1

Length

3 to 4 m1

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

cool stuff

Fun facts

Simosaurus had large openings behind its eyes called upper temporal fossae, which were bigger than its eye sockets.1

Its jaw joint was set far back, projecting beyond the main part of the skull, giving it a unique bite.1

Simosaurus had a flattened trunk that prevented side-to-side swimming, unlike most other nothosaurs.1

It swam using powerful downstrokes of its forelimbs, but its upstroke was weak, making it a moderately strong swimmer.1

The first Simosaurus fossils were found in Lunéville, France, and described by German paleontologist Hermann von Meyer in 1842.1

Simosaurus is known from the Muschelkalk deposits in Germany, where it appears in layers marked by the ammonite Ceratites nodosus.1

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

For dino experts

Scientific name: Simosaurus
Named by: Meyer 18422
Group: Other sea reptiles
Family / clade: Simosauridae2
Classification: Nothosauria > Sauropterygia2
Age of the rocks: 247 to 201 million years ()2
Rock formations: Jilh, Erfurt, Gevanim2
Countries: Germany, France, Saudi Arabia, Israel, Italy2
Fossil records: 15 in the Paleobiology Database2
Discovery: German paleontologist Christian Erich Hermann von Meyer named Simosaurus in 1842 based on a skull from Lunéville, France. That original skull has since been lost.1
Still debated: Scientists debate whether Simosaurus was a nothosaur, a pachypleurosaur, or a more primitive sauropterygian.1

Where the facts come from

Simosaurus (en.wikipedia.org)
Simosaurus 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.