atlantic portuguese man-of-war physalia physalis jellyfish-like poisonous marine hydrozoan washed out on the shore

animal atlantic beach being blue caribbean close closeup cnidaria cuba dangerous days dead deadly drifting freefloating gasfilled hydrozoan invasive jellyfish lethal man manowar manwar marine ocean open painful physalia physaliidae physalis poisonous portuguese predator sand sea seasonal seaweed shore siphonophore sting tentacles transparent varadero venomous washed water winter zooid