Ichthyosaurus
Ichthyosaurus was a fast-swimming marine reptile that looked like a dolphin but was not a dinosaur. It lived in the oceans during the time of the dinosaurs and hunted fish and squid with its long, toothy snout.1
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Fun facts
Ichthyosaurus could not suck in its prey like some fish. It had to bite and grab food with its teeth.1
It was a pursuit predator, meaning it chased after its food by swimming very fast.1
Ichthyosaurus gave birth to live young, not eggs, because it lived entirely in the water.2
Its eyes were large and it relied on sight to hunt, possibly also using its sense of smell.1
Fossils of Ichthyosaurus have been found in rocks that are between 227 and 100 million years old.5
The name Ichthyosaurus means 'fish lizard', but it was a reptile, not a fish.1
Most asked questions about Ichthyosaurus
?How big was Ichthyosaurus?
It was smaller than many other ichthyosaurs. The largest species, I. somersetensis, reached about 3 to 3.3 metres (9.8 to 10.8 feet) long, while other species like I. communis were only about 2 metres (6.6 feet) long.1
?What did Ichthyosaurus eat?
It ate fish and squid-like animals called cephalopods, especially belemnites. It was a fast swimmer that chased and grabbed its food with its teeth.1
?Did Ichthyosaurus lay eggs?
No, it gave birth to live babies in the water. Fossils show pregnant females with tiny Ichthyosaurus inside them, so they never came onto land to lay eggs.1
?Was Ichthyosaurus a dinosaur?
No, it was a marine reptile called an ichthyosaur, not a dinosaur. Dinosaurs lived on land, while Ichthyosaurus lived in the ocean.3
?How fast could Ichthyosaurus swim?
It was a fast swimmer that used thunniform locomotion, meaning it moved like a tuna or mackerel. Scientists think it could swim very quickly to chase prey.1
?When did Ichthyosaurus live?
It lived during the Early Jurassic Period, about 201 to 174 million years ago. Fossils have been found in Europe, especially in England, Germany, and Portugal.1
?Could Ichthyosaurus breathe underwater?
No, it breathed air like a dolphin or whale. It had to come to the surface to breathe, even though it lived its whole life in the ocean.4
?Why did Ichthyosaurus have big eyes?
It had large eyes to help it see well while hunting. It relied mostly on its sense of sight, possibly along with smell, to find fish and squid.1
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Myth buster
Myth: Ichthyosaurus was a dinosaur.
Truth: Ichthyosaurus was a marine reptile, not a dinosaur. Dinosaurs lived on land, while ichthyosaurs swam in the sea.1
For dino experts
- Scientific name
- Ichthyosaurus
- Named by
- Koenig 18185
- Group
- Ichthyosaurs
- Family / clade
- Ichthyosauridae5
- Classification
- Ichthyosauria > Ichthyosauromorpha5
- Age of the rocks
- 227 to 100 million years (Norian / Albian)5
- Rock formations
- Blue Lias, White Lias, Alum Shale5
- Countries
- United Kingdom, France, Chile, USA, Germany, Belgium5
- Fossil records
- 101 in the Paleobiology Database5
- Also known as
- Eurypterygius, Gryphus (older names now counted as the same animal)5
- Discovery
- Ichthyosaurus was named by the scientist Charles Koenig in 1818, based on fossils found in England.5
- Still debated
- Scientists still debate exactly how many species of Ichthyosaurus existed, because many fossils are incomplete.2
Where the facts come from
- Ichthyosaurus (en.wikipedia.org)
- PBDB Taxon (paleobiodb.org)
- What is an ichthyosaur? The real sea dragons that once swam beneath the waves | Natural History Museum (nhm.ac.uk)
- Ichthyosauria (ucmp.berkeley.edu)
- Ichthyosaurus in The Paleobiology Database (CC BY 4.0): age, places, rock formations, classification.
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