
Tourists have been banned from swimming along a seven-mile stretch of Costa Blanca because of sea creatures with a potentially fatal sting.
Red flags have popped up on Spanish beaches after blue dragons, nicknamed the ‘most beautiful killer in the ocean’, appeared.
The sea slug, also known as Glaucus atlanticus, eats the deadly Portuguese man o’ war and other venomous sea beasts.
The blue dragons quickly absorb the stinging cells from their food and store them, giving them a far more potent sting than their prey.
Typical symptoms of the blue dragon’s sting include nausea, pain, vomiting and acute allergic contact dermatitis.
Guardamar del Segura mayor Jose Luis Saez said the sea ban order will remain in place until further notice.
‘Bathing is prohibited following the appearance on Vivers Beach of two specimens of Glaucus atlanticus, known as the Blue Dragon,’ he said.

He added: ‘We remind people that despite its bright and striking colour and its small 1.5-inch size, they should stay away from this animal because of its sting.
‘Guardamar del Segura Town Hall has launched a preventive operation to detect possible specimens carried by ocean currents. Town hall workers are closely following the evolution of the situation and will inform people about the different measures to be taken.’
Beachgoers have been urged not to touch the creatures, even with gloves on. If you stumble across one, alert lifeguards.
Saez added: ”If you get stung, wash the area affected with salt water and head to your nearest first aid point or health centre. These creatures are poisonous and their stings can cause nausea, pain and vomiting.’
Despite the warnings, Vivers Beach was full of people yesterday, though fewer were seen in the sea.
Lifeguards will remind tourists and locals today about the ban, according to local reports, although sunseekers will still be allowed to head to beaches if they don’t take a dip in the sea.

Last month, a huge chunk of skin was torn off the leg of an Italian pensioner as lifeguards ordered people out of the sea at the British holiday hotspot of Majorca.
Police said part of her skin around the wound had been ripped off by a mystery creature, but it didn’t affect muscle tissue.
Marine biodiversity expert Aniol Esteban told local press, based on photos: ‘Our hypothesis is that the attack may have been caused by a bluefish.’
Other marine biologists said it had all the hallmarks of an attack by a triggerfish, colourful, oval-shaped marine fish which have strong jaws and sharp teeth adapted for crushing shells.
Blue sharks, which rarely bite humans but have been implicated in several biting incidents, have forced the temporary closure of beaches on the Costa del Sol and Costa Blanca in recent years.
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