Which jellyfish is the largest known jellyfish species?

The lion’s mane jellyfish is the largest known jellyfish species.

Its bell can grow to more than 2 metres across, while its trailing tentacles may extend for many metres. The species is named for the dense, reddish-brown mass of tentacles surrounding its bell, which resembles a lion’s mane.

Lion’s mane jellyfish are cold-water animals found in the northern Atlantic, northern Pacific and Arctic oceans. They drift with currents but can also pulse their bells to move through the water. Their tentacles carry stinging cells called nematocysts, which capture prey such as small fish and plankton.

Size records can be difficult to compare because tentacles stretch and contract. The species is still recognized as the largest jellyfish by overall dimensions, while other jellyfish may be heavier in particular specimens.