Portuguese Man-of-War

The Portuguese man-of-war is a floating marine organism found in warm ocean waters worldwide, easily recognized by the translucent, gas-filled float that rises above the surface like a sail and gives the animal its name, often tinged blue, pink or purple. Though it looks and stings like a single jellyfish, it is in fact a siphonophore, a colony of specialized, genetically identical organisms called zooids that function together as one, each responsible for tasks such as floating, feeding, digestion or reproduction. Long tentacles trailing beneath the float, which can extend many metres, are armed with stinging cells used to paralyze small fish and other prey, and the same venom can deliver a painful and occasionally dangerous sting to humans who brush against a stranded or floating specimen. It has no means of self-propulsion and drifts wherever the wind and ocean currents carry it, sometimes washing ashore in large numbers. Despite its jellyfish-like appearance, the man-of-war belongs to a different group of cnidarians entirely.