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Eopolycotylus

Say it: EE-oh-pol-ee-KOT-ih-lus
Name means: “early cup”2
Ate: MeatPlesiosaursLate CretaceousNot technically a dinosaur

Eopolycotylus is a plesiosaur, a marine reptile that lived in the ocean during the time of dinosaurs. It had a long neck, a big body, and four flippers to swim. It was a fast hunter in the ancient seas of Utah.21

Fun fact: this sea reptile swam while dinosaurs walked on land. Everyone calls them dinos, but they were a different branch of reptiles.
Lived
94 to 90 million years ago2
Late Cretaceous
Fossils found in
Big Water, Tropic Shale, Kane County, Utah, USA1
Food
Meat2
Length
2.5 to 3.5 m2
estimate based on related polycotylids
Weight
150 kg to 300 kg2

When did it live?

Triassic
Jurassic
Cretaceous
252 million years ago20114566, the asteroid

How big was it?

How long was it?

Eopolycotylus about 3.5 m longA dog about 1 mA bicycle about 1.8 mA car about 4.5 mAn elephant, the biggest land animal today about 6.5 m

How heavy was it?

as heavy as 10 big dogs
as long as 4 dogs nose to tailas long as 19 bananas end to endas heavy as 60 watermelons

How big was Eopolycotylus compared to YOU?

Just maths in your browser. Nothing is saved or sent anywhere.

cool stuff

Fun facts

1

Eopolycotylus is a type of plesiosaur called a polycotylid, which had a short neck and a long snout.2

2

Its fossils were found in the Tropic Shale, a rock layer that formed from mud on an ancient seafloor about 91 million years ago.1

3

The only known specimen is a partial skeleton that includes parts of the skull, jaws, and flippers.1

4

Eopolycotylus lived during the Turonian stage of the Late Cretaceous, when the Western Interior Seaway covered much of central North America.1

5

It was a fast swimmer, using its four flippers to chase prey in the warm, shallow sea.2

6

Scientists think Eopolycotylus gave birth to live young in the water, just like modern whales and dolphins.1

AI-madeAI-made picture of Eopolycotylus
An AI-made picture of how Eopolycotylus 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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Scientific name
Eopolycotylus
Named by
Albright et al. 20072
Group
Plesiosaurs
Family / clade
Polycotylidae2
Classification
Plesiosauria > Sauropterygia2
Age of the rocks
94 to 90 million years (Turonian)2
Rock formations
Tropic Shale2
Countries
USA2
Fossil records
1 in the Paleobiology Database2
Discovery
Eopolycotylus was named in 2007 by paleontologists Albright, Gillette, and Titus, based on a fossil found near Big Water, Utah.21
Still debated
Scientists are still unsure about the exact length and weight of Eopolycotylus because only one partial skeleton has been found.2

Where the facts come from

  1. PBDB Taxon (paleobiodb.org)
  2. Eopolycotylus 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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