The deadly jellyfish washed up on Lusty Glaze beach in the county. Authorities have urged members of the public to stay away from any Portuguese man o’ war that wash up on the beach. The sting from a Portuguese man o’ war is extremely painful and powerful enough to kill fish and even occasionally humans.
The man o’ war is a colony of organisms working in symbiosis rather than a single creature.
The tentacles can grow up to a staggering 165 feet long, 50 metres.
One of the jellyfish was previously seen near St Agnes on August 30.
Sam Lovett, 22, spotted one of the venomous creatures.
He said: “I am quite into my marine biology and marine life so I was quite certain that it was a Portuguese man o’ war.
“I took some pictures and as soon as I got the signal I looked it up and it fit the description.
“It didn’t look like a normal jellyfish, it almost looked like a blown-up sandwich bag, but the blue and pink colours gave it away.
“We were very careful around it.
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“The colony floats from the bottom of an air-filled float and has many long thin tentacles, often up to 10 metres in length, hanging below that it uses to catch fish and which can inflict a very powerful sting.
“Contact with the Portuguese man o’ war usually results in extremely painful stings that can leave nasty welts, lesions, and ulcerations.
“In a few cases, the stings can cause anaphylactic shock, and young children are especially at risk.
“And be careful as they can still sting when they appear dead washed up on the beach, so we advise people to leave well alone and keep animals away.
“Recommended treatment for man-of-war stings includes immediate removal of the tentacles with tweezers and rubber gloves by washing in saltwater first, but don’t rub the area as this makes the sting worse.”