Dino card No. 0435 of 2,015

Colymbosaurus

Say it: ko-LIM-bo-SORE-us

Name means: “diver lizard”2

Ate: MeatPlesiosaursMiddle Jurassic to Early CretaceousNot technically a dinosaur

Colymbosaurus was a plesiosaur, a marine reptile that swam in the seas with a long neck and flippers. It was not a dinosaur, but a fierce hunter of the ocean.2

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

Lived

168 to 113 million years ago2

Middle Jurassic to Early Cretaceous

Fossils found in

Fossils of Colymbosaurus have been found in the United Kingdom, Norway, France, and Russia.2

Food

Meat2

Artist's life restoration of Colymbosaurus — How Colymbosaurus may have looked, by Connor Ashbridge. CC BY-SA 4.0, via Wikimedia Commons. Scientists still argue about colours and details.

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

cool stuff

Fun facts

Colymbosaurus lived from about 168 to 113 million years ago, during the Jurassic and Cretaceous periods.2

It belonged to a group called Cryptoclididae, which were plesiosaurs with long necks and small heads.1

There were at least two valid species: Colymbosaurus megadeirus and Colymbosaurus svalbardensis.1

Colymbosaurus trochanterius is not considered a valid species, but some fossils are still referred to Colymbosaurus.1

Fossils have been found in the Kimmeridge Clay Formation in the UK, which was a shallow sea at the time.1

Colymbosaurus was actively mobile and lived in the water, likely swimming near the surface.2

Myth buster

Myth: Some people think Colymbosaurus was a dinosaur.

Truth: Colymbosaurus was a plesiosaur, a marine reptile, not a dinosaur.2

For dino experts

Scientific name: Colymbosaurus
Named by: Seeley 18742
Group: Plesiosaurs
Family / clade: Cryptoclididae2
Classification: Plesiosauria > Sauropterygia2
Age of the rocks: 168 to 113 million years (Bathonian to Aptian)2
Rock formations: Kimmeridge Clay, Portland Stone, Agardhfjellet2
Countries: United Kingdom, Norway, France, Russia2
Fossil records: 18 in the Paleobiology Database2
Discovery: Colymbosaurus was named by Harry Seeley in 1874 based on fossils from the UK.2
Still debated: Scientists debate which species belong to Colymbosaurus, because some fossils are incomplete and hard to compare.1

Where the facts come from

Anatomy of Colymbosaurus megadeirus (Reptilia, Plesiosauria) from the Kimmeridge Clay Formation of the U.K., and high diversity among Late Jurassic plesiosauroids (tandfonline.com)
Colymbosaurus 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.