Climate change is causing the 'fire worm' or Hermodice carunculata, a marine animal that can cause painful stings, to migrate northward in Italy, expanding its habitat from the southern coasts to the Tuscan Archipelago and the Adriatic Sea. Initially found near rocky substrates, this coral-eating worm feeds on various marine life and can sting fishermen in nets. Its sting, while not fatal, can lead to painful symptoms akin to a jellyfish sting, making swimming unpleasant. The increased sightings of the fire worm are linked to rising sea temperatures, with a higher frequency in summer and a decrease in spring and autumn, nearly disappearing in winter. Tourists are advised to take caution, especially in areas with rocks and reefs, and seek medical attention for sting symptoms.