The wheelie-bin sized jellyfish was caught on camera by a diver in the Percuil Estuary, near St Mawes
Those of a squeamish disposition should look away now. However if large marine animals intrigue you, then this video is an absolute must-watch.
The largest species of jellyfish in British waters, which is bigger than a fully-grown dog, has been filmed off the coast of Cornwall by a brave diver.
Matt Slater uploaded a two-minute clip of the animal to YouTube last week (23 June), which has since attracted more than 10,000 views.
It’s easy to see why this video has proven so popular, as Matt gets close enough to see how the barrel jellyfish moves through the water.
Although this particular species, rhizostoma pulmo, does not have any stinging tentacles, contact can cause skin irritation, comparable to that of a nettle.
Barrel jellyfish can grow up to 80cm wide and weigh up to 30kg, and the true scale of this particular invertebrate is shown when a fully-grown dog paddles past.
To see the barrel jellyfish in its natural habitat, click on the video below: