Although they may look like a jellyfish at first glance, Portuguese man of war – or blue bottles – are in fact a distant relative known as a siphonophore. What distinguishes these marine creatures is that they are not single organisms, but rather floating colonies made up of hundreds of individuals that perform different roles. While the float (also known as the airbag) is the most striking part of the community, it is the members below the surface tasked with defence and attack – the dactylozooids – that leave a lasting impression on us!

These particular polyps have evolved a superlong tentacle smothered with nematocysts, which work as a collective to make for a formidable weapon. It’s the mind-boggling length these tentacles can reach – up to half a football pitch – that makes them such a high risk to us. They stretch so far from the main body that it’s almost impossible to see them coming. Even after getting stung, there’s a good chance you still won’t be able to spot the culprit.

DANGER FACTOR – Short-lived, intense pain and red welts on skin. On rare occasions, a sting can also trigger breathing difficulties and other allergic reactions.

Float length: 30cm (12in)

Tentacle length: < 50m (164 ft)