Dino card No. 1634 of 2,015

Shonisaurus

Say it: SHON-ih-SORE-us

Ate: MeatIchthyosaursLate TriassicNot technically a dinosaur

Shonisaurus was a giant marine reptile that swam in the oceans during the Triassic Period. It was not a dinosaur, but a kind of ichthyosaur, with a long body and flippers. It could grow as long as a gray whale!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

234 to 201 million years ago3

Late Triassic

Fossils found in

Fossils have been found in Nevada, USA, and also in Italy and Germany.2 3

Food

Meat2

Length

15 to 21 m2 1

Scientists estimate adults reached 15 to 21 metres, though some sources say about 15 metres.

Artist's life restoration of Shonisaurus — How Shonisaurus may have looked, by Creator: Dmitry Bogdanov. CC BY 3.0, via Wikimedia Commons. Scientists still argue about colours and details.

When did it live?

Triassic

Jurassic

Cretaceous

252 million years ago20114566, the asteroid

How big was it?

cool stuff

Fun facts

Shonisaurus had a very long body with about 60 vertebrae before its hips, making it look a bit like a giant sea serpent.1

Its tail had only a slight bend, not a strong one like many other ichthyosaurs, so it may have swum differently.1

Adult Shonisaurus may have lost their teeth, because teeth are only found in young fossils. Scientists think adults might have sucked up food instead of biting.2

Its flippers were long and slender, with only two or three main fingers, unlike many other ichthyosaurs.1

Shonisaurus lived about 233 to 201 million years ago, during the Late Triassic.2

About 40 Shonisaurus skeletons have been found in Nevada, but many are incomplete and poorly preserved.1

Myth buster

Myth: Some people think Shonisaurus was a dinosaur because it lived in the sea and looked like a sea monster.

Truth: Shonisaurus was not a dinosaur. It was an ichthyosaur, a group of marine reptiles that lived at the same time as dinosaurs but were a different group.2

For dino experts

Scientific name: Shonisaurus
Named by: Camp 19763
Group: Ichthyosaurs
Family / clade: Shastasauridae3
Classification: Ichthyosauria > Ichthyosauromorpha3
Age of the rocks: 234 to 201 million years (Carnian to Rhaetian)3
Rock formations: Luning, Durrenstein, Exter3
Countries: USA, Italy, Germany3
Fossil records: 5 in the Paleobiology Database3
Discovery: Shonisaurus was named by Charles L. Camp in 1976, based on fossils from Nevada, USA. The first fossils were found in the Luning Formation.2
Still debated: Scientists still debate how big Shonisaurus really got, with estimates ranging from 15 to 21 metres, and whether it had teeth as an adult.2 1

Where the facts come from

A reinterpretation of the Upper Triassic ichthyosaur Shonisaurus : Journal of Vertebrate Paleontology: Vol 19, No 1 (tandfonline.com)
PBDB Taxon (paleobiodb.org)
Shonisaurus 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.