Dino card No. 1395 of 2,015

Peloneustes

Say it: pel-oh-NEW-steez

Name means: “mud swimmer”1

Ate: FishPlesiosaursMiddle JurassicNot technically a dinosaur

Peloneustes was a pliosaur, a kind of short-necked plesiosaur that lived in a shallow sea. It had a long, narrow snout like a dolphin and many sharp teeth for catching fish. This marine reptile was a fast and fierce hunter in the water.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

165 to 162 million years ago3

Middle Jurassic

Fossils found in

England, France, and Germany3 1

Food

Fish1

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

cool stuff

Fun facts

Peloneustes lived about 165 to 161 million years ago during the Middle Jurassic period.3

Its name means 'mud swimmer' because its fossils were found in mud from an ancient sea.1

Peloneustes had a long, narrow snout that was shaped like a dolphin's beak. This helped it move quickly through the water.1

It had 30 to 31 teeth in its upper jaw and 36 to 44 teeth in its lower jaw. The teeth were sharp and slightly curved for piercing fish.2

Peloneustes shared its sea home with other marine reptiles like ichthyosaurs and other plesiosaurs. At least five different pliosaurids lived in the same area.1

The sea where Peloneustes swam was only about 30 to 50 metres (100 to 160 feet) deep. It was a shallow inland sea.1

AI-made picture of Peloneustes — An AI-made picture of how Peloneustes 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: Peloneustes
Named by: Lydekker 18893
Group: Plesiosaurs
Family / clade: Pliosauridae3
Classification: Plesiosauria > Pliosauridae > Sauropterygia3
Age of the rocks: 165 to 162 million years (Callovian)3
Rock formations: Oxford Clay, Ornatenton, Argiles de Montaubert3
Countries: United Kingdom, France, Germany3
Fossil records: 12 in the Paleobiology Database3
Discovery: Peloneustes was first described as a species of Plesiosaurus by Harry Govier Seeley in 1869. Richard Lydekker gave it its own genus name in 1889.1
Still debated: Scientists are not sure if Peloneustes was a close relative of Pliosaurus or a more early-diverging pliosaurid. They are still studying its family tree.1

Where the facts come from

Peloneustes (en.wikipedia.org)
The cranial anatomy and taxonomy of Peloneustes philarchus (Sauropterygia, Pliosauridae) from the Peterborough Member (Callovian, Middle Jurassic) of the United Kingdom (onlinelibrary.wiley.com)
Peloneustes 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.