Portuguese man o' war
Scientific classification
Kingdom: Animalia
Phylum: Cnidaria
Class: Hydrozoa
Order: Siphonophora
Family: Physaliidae
Genus:Physalia
Species:physalia
Binomial name
Physalia physalia
Portuguese man o' war (genus Physalia) also known as (sea wasp) commonly thought of as a jellyfish is actually a colony of four sorts of polyps. A similar animal is the velella. The man o' war's float is bilaterally symmetrical with the tentacles at one end, while the velella is radially symmetrical with the sail at an angle. Also the man o' war has a siphon, while the velella doesn't.

The Portuguese man o' war has an air bladder that allows it to float on the surface of the ocean. It has no means of propulsion and is pushed by the winds and the current. Below the jelly a long tentacles dangle, sometimes streching to over fifty meters in length. These tentacles contain poisons that stun and kill small sea creatures which the man o' war then consumes. Portuguese man o' war are an important source of food to sea turtles, which have immunity to the poison. The Portuguese man o' war can be found on the coast of North America and Europe as well as in other areas of the world.

The Portuguese man o' war has stings potentially dangerous to humans; these stings have been responsible for several deaths.