Dino card No. 1859 of 2,027

Undorosaurus

Say it: un-dor-oh-SORE-us

Name means: “lizard from Undory”1

Ate: MeatIchthyosaursLate Jurassic to Early CretaceousNot technically a dinosaur

Undorosaurus was a huge, fish-shaped marine reptile that swam in the seas during the Late Jurassic. It had a long snout full of strong teeth and flippers like paddles to zoom through the water.1 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

162 to 143 million years ago4

Late Jurassic to Early Cretaceous

Fossils found in

Russia (near the Volga River, Moscow Oblast), Svalbard (Norway), and Poland1

Food

Meat2

Length

4 to 6 m1

for the type species

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

How long was it?

as long as 6 dogs nose to tailas long as 33 bananas end to end

How big was Undorosaurus compared to YOU?

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cool stuff

Fun facts

Undorosaurus had very strong teeth, unlike its close relative Ophthalmosaurus which had almost no teeth.1

Some scientists once thought Undorosaurus was the same as Ophthalmosaurus, but later studies showed it was a different genus because of its teeth and hip bones.1

The species Undorosaurus trautscholdi was named after a geologist named Hermann Trautschold, who found its fossil in 1878.1

Undorosaurus lived about 150 to 145 million years ago, during the Late Jurassic period.1

Its fossils have been found in three different countries: Russia, Norway (Svalbard), and Poland.1

The first Undorosaurus fossil was a partial skeleton with a skull, found near the Volga River in Russia.1

AI-made picture of Undorosaurus — An AI-made picture of how Undorosaurus 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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For dino experts

Scientific name: Undorosaurus
Named by: Efimov 19994
Group: Ichthyosaurs
Family / clade: Ophthalmosauridae4
Classification: Ichthyosauria > Ichthyosauromorpha4
Age of the rocks: 162 to 143 million years (Oxfordian / Tithonian)4
Countries: Russia4
Fossil records: 6 in the Paleobiology Database4
Discovery: Undorosaurus was named by Russian paleontologist Vladimir M. Efimov in 1999. The first fossils were found near Gorodischi on the Volga River in Russia.1
Still debated: Scientists still debate whether some species from Norway and Poland really belong to Undorosaurus or are separate animals.1 3

Where the facts come from

Undorosaurus (en.wikipedia.org)
PBDB Taxon (paleobiodb.org)
Revision of Undorosaurus, a mysterious Late Jurassic ichthyosaur of the Boreal Realm - ADS (ui.adsabs.harvard.edu)
Undorosaurus 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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