The good people at West Kirby Lifeboat have issued a warning - and advice - about what to do if you find one of these washed up on a local beach.

It's a Portuguese man of war, a jellyfish-like marine animal. They have tentacles with coiled stingers which deliver a very powerful and painful venom. The sting is meant to paralyze small fish until they can be eaten. In humans, reactions are normally mild to moderate, but in rare cases, they can be life-threatening.

So the warning - and basic advice - is: DON'T TOUCH IT!

Says the Lifeboat team: "They can give a nasty sting even when dead."

Rest assured this was hardly a full scale of invasion of creatures which have been likened to 'sea aliens'.

There were reports of another man of war further up the coast, but even numbering two we don't need to be too concerned.

That said, people on beaches with dogs and children might like to make sure that their charges don't start sniffing around or investigating something potentially dangerous.

Interesting fact: Although it superficially resembles a jellyfish, the Portuguese man o' war is in fact a siphonophore. Like all siphonophores, it is a colonial organism, made up of many smaller units called zooids.

All zooids in a colony are genetically identical, but fulfill specialised functions such as feeding and reproduction, and together allow the colony to operate as a single individual.

Fancy that!

Another interesting fact: The Portuguese Man O'War is named after the 18th Century armed sailing ship - as it was believed they look like one at full sail.

I think you have to use your imagination.

Wirral Council says: "If you see a Portuguese man of war, please call our contact centre on 0151 606 2000 and our parks team will remove it."

Should you be unlucky enough to be stung, first, if you can, seek help from a lifeguard or someone else with first aid training; rinse the affected area with seawater (not fresh water); remove any spines from the skin using tweezers or the edge of a bank card; and then soak the affected area in very warm water (as hot as can be tolerated), or use hot flannels instead.

People took to social media to share their memories of these extraordinary creatures:

"Remember swimming off whistling sands in North Wales as a kid and one swam past me. Beautiful but rather scary."

"When I was a kid in Devon, I can remember a beach being closed because a mob of these had washed ashore."

"Wow so beautiful. But deadly! 'Usually found washed up ashore in large groups' - so hopefully this one was a loner."