A reptile shaped like a dolphin
Reptiles, fish and mammals have all arrived at the same streamlined shape for fast swimming.
In the sea · Sea reptiles
Ichthyosaurus
Fish lizard · IK-thee-oh-SORE-us
A sleek sea reptile shaped like a dolphin, with a long toothy snout, huge eyes, four flippers and a fish-like tail.
- Size
- About 2 to 3m long
- Lived
- About 200 to 190 million years ago
- Found in
- Dorset and Somerset, England; also Belgium and Germany
Swims after you with flicks of its tail. Move your pointer and see.
To scale
How big was it?
The bars are drawn to the same scale. On these pages the animals are sized in proportion to each other as far as a screen allows: the giants are shrunk a little and the smallest are enlarged, so that you can see them all.
Good to know
Six things about the ichthyosaurus
Enormous eyes
A ring of bone supported each huge eye. It could see in dim, deep water.
Found by Mary Anning
In 1811 Mary Anning, aged twelve, and her brother found the first skeleton to be studied by scientists.
Babies born tail first
Fossils show mothers with young inside them, and one giving birth.
A fast swimmer
It may have reached 25 miles an hour.
Even its droppings
Fossil droppings, full of fish scales and squid hooks, were first recognised from ichthyosaurs.
The real thing
Photos of the ichthyosaurus
Photos are from Wikimedia Commons, used under the free licences shown. They have been resized, and cropped where they appear in link previews.
What it ate
Fish and squid-like animals called belemnites.
How we know
Hundreds of skeletons come from the Dorset coast. Some German fossils show the outline of the skin.
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