DEADLY Portuguese man o' war jellyfish have been found washed up on Dorset beaches.

The creatures, which are armed with poisonous tentacles that deliver a painful sting, can - in rare cases - prove fatal to young children or susceptible adults.

Last month more than 140 were sighted off the Cornish coast - beating all previous records for that area.

Now Dorset Wildlife Trust (DWT) has confirmed sightings of the Portuguese man o' war at Kimmeridge, Charmouth and Chesil beaches.

DWT says whilst swarms of these creatures - which are not actually jellyfish - in Dorset are unusual, the Portuguese man o’ war has appeared before.

The largest swarm was recorded in August and September 2008, with reports spanning Charmouth to Swanage. A much smaller swarm was recorded the same time the following year and in 2012.

Despite its appearance the Portuguese man o' war, whose venomous tentacles can grow up to 50 meters long, is not a jellyfish but a marine animal known as a siphonophore. Along with the smaller Indo-Pacific man o' war they are responsible for thousands of human stings in Australia each summer

DWT marine conservation officer Emma Rance said: "Whilst they have been described as ‘invading’ our beaches, so far, only a handful have actually been sighted in Dorset this Autumn.

"If you find one, we advise that you do not touch them, as they can sting even when dead.

"These are fascinating and beautiful creatures and are only seen in very rare cases on our seashores, so Dorset Wildlife Trust is really keen to hear about any sightings in Dorset.”

They are thought to have arrived on the south coast via the Gulf Stream, due to the strong south westerly winds that have been pounding our coastlines recently, bringing with them an influx of marine wildlife usually found in the open Atlantic Ocean.

Until now, there have been no known Portuguese man o’ war in Dorset. However, each year DWT do frequently record individuals from seven other oceanic jellyfish species in Dorset.

If you are worried you may have been stung, seek medical assistance as soon as possible.

Email with any sightings.