lion's mane jellyfish Cyanea capillata

Lion's mane jellyfish

  Virtual animals


The lion’s mane jellyfish is one of the impressive figures that you will be able to discover in the Grand Large experience. A giant among jellyfish, it represents plankton, an essential link in the food chain for the equilibrium of the marine ecosystem.

lion's mane jellyfish Cyanea capillata

Identity card

lion's mane jellyfish

Scientific name:
Cyanea capillata
Year of description:
Linnaeus, 1758
IUCN Status:
Not Evaluated

Circumpolar, North Atlantic, Northwest Atlantic, North Pacific


Between 0 - 85 m


229 cm maximum, diameter between 50 and 100 cm.


Fish, crustaceans and other jellyfish.

lion's mane jellyfish Cyanea capillata

The tentacles may reach the record-breaking length of 36.6 metres, longer than a blue whale.

Shrimps and small fish, young mackerel, cod and horse mackerel live in the middle of their tentacles to escape their predators and make the most of any leftover food.

Lion’s mane jellyfish are also prey to large predators: leatherback turtle and ocean sunfish have a good appetite for jellyfish, as do many seabirds.

did you know?

Where is the animal to be found?

Despite their size, jellyfish are a type of plankton, that’s to say they drift along with the ocean currents. They live in the open sea, usually at depths not exceeding 20 metres, but the winds and currents can carry them towards the coast.

This jellyfish is found in the Arctic polar circle in the northern Pacific (from Japan to California) and in the northern Atlantic (in the St-Lawrence, to the north of the United States and to the north of Europe). In France, it can be found in the English Channel and the North Sea.

How can it be recognised?

The lion’s mane jellyfish, Cyanea capillata, owes its name to its great number of very fine hair-like tentacles. Furthermore, the Latin word capillata means hairy. There are four undulating oral arms in the middle of these tentacles (sometimes as many as 800!).

The diameter of its bell varies between 50 to 100 cm; in the coldest waters, the diameter can be as large as 2 metres. This means that the lion’s mane jellyfish is one of the biggest jellyfish in the world.

The bell is divided into 8 lobes which alternate with eight rhopalia, which are the jellyfish’s sense organs. The colour of these jellyfish varies with their age: juveniles are pink or yellow, and their colour becomes darker as they grow older, turning red or a brownish orange.

There are millions of cnidocytes on their tentacles. These are stinging cells which, when they come into contact with their prey (or the skin of a bather), trigger a minuscule stinger that injects their venom. This is how jellyfish paralyse their prey: fish, crustaceans and other jellyfish. They are then taken from the tentacles to the oral arms to the mouth.

What is distinctive about it?

The lion’s mane jellyfish have a painful sting, above all once they have reached their maximum size, that is to say at the end of the summer and in the autumn. Even when beached, jellyfish tentacles may continue to have a sting for several hours. This species is thought to be less dangerous off French coasts.

Where can I find it at Nausicaá?

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lion's mane jellyfish Cyanea capillata

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