Portuguese man o' war

This article is about the marine invetebrate. For other uses, see Man O' War.

Portuguese Man O' War
Scientific classification
Kingdom:	Animalia
Phylum:	Cnidaria
Class:	Hydrozoa
Order:	Siphonophora
Family:	Physaliidae
Genus:	Physalia
Species:	P. physalis
Binomial name
Physalia physalis (Linnaeus, 1758)

The Portuguese Man O' War (Physalia physalis), also known as the bluebubble or bluebottle, is commonly thought of as a jellyfish but is actually a siphonophore—a colony of four sorts of polyps.

A similar group of animals are the chondrophores.

Structure

The Man O' War's float is bilaterally symmetrical with the tentacles at one end, while the chondrophores are radially symmetrical with the sail at an angle. Also the Man O' War has a siphon, while the chondrophores do not.

The Portuguese Man O' War has an air bladder; known also as a pneumatophore or sail, 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. The sail is filled with air, but may build up a high concentration of carbon dioxide (up to 90%). The bladder must stay wet to ensure survival; every so often it may roll slightly to wet the surface of the float. To escape a surface attack, the pneumatophore can be deflated allowing the Man O' War to briefly submerge.

Below the main body dangle long tentacles, sometimes reaching 165 feet (50 meters) in length below the surface, although 30 feet (10 meters) is the average. They sting and kill small sea creatures using poison-filled nematocysts then draw the prey in to the gastrozooids, which are yet another different type of polyp that surround and digest it. Gonozooids are responsible for reproduction.

Poison

The sting from the tentacles is potentially dangerous to most humans; these stings have been responsible for several deaths, but usually only cause excruciating pain. Detached tentacles and specimens washed up on shore can sting just as painfully as the full creature in the water, for weeks after detachment. The venom can travel up to the lymph nodes and may cause, depending on the amount of venom, more intense pain. In extreme cases medical attention is necessary.

According to a study done by Dr. Geoffrey Isbister of Newcastle, Australia's Mater Hospital in 2003 through 2005, the best treatment for a sting is to apply hot water to the affected area. Hot water used in the study was fixed at 45 degrees Celsius (113 Fahrenheit). The hot water eases the pain of a sting by degrading the toxins.

Applying ice to the area of the sting is also a fairly effective way to suppress the pain. Ice works by making the toxins less active and reduces the sensation and therefore pain of the area of skin around the ice. Additionally, ice constricts blood vessels, reducing the speed at which the poison travels to other parts of the body, including the brain; heat has an opposite effect. It was originally thought that applying ice was the best way of dealing with Man O' War stings before the study was done. Lifesavers around the world still use ice to treat the stings of this species.

Ointments that are specifically designed to treat Man O' War stings seem to have little effect.

The use of vinegar to treat stings is controversial. It appears that vinegar can make the sting more painful in some cases, while other victims report relief after applying vinegar. One should never apply vinegar while the tentacle is still attached to the body, as this will cause the stinging cells to inject more venom.

It is often confused with a jellyfish, which is incorrect and may lead to improper treatment of stings, as the poison is different. A second sting may lead to an allergic reaction.

Origin of the name

The Man O' War is named for its air bladder, which looks similar to a man of war under sail, namely a Portuguese Caravel.

Trivia

• Wrestler Aldo Montoya was once nicknamed "Man O' War".
• In the book Perdido Street Station, by China Mieville, Man O' War are gigantic flying jellyfish capable of supporting riders.
• In the book "Stormbreaker", the antagonist Herod Sayle owns an enormous Portuguese Man O' War, which he uses as a deathtrap much later in the book. In the movie adaptation, however, the "Portuguese Man O' War" bore no resemblance to the actual Man O' War, and had the ability to dematerialize full skeletons not possessed by the actual creature.
• In the expasion of the game Age of Mythology, an Atlantean civilization that adores Kronos or Oranos can choose Helios as a minor god of the Mythic age, which grants the posibility of creating a naval unit called simply Man O' War; a giant Portuguese Man O' War that shoots lightning from its tentacles.

External links

• Siphonophores.org - General information on siphonophores, including the Portuguese man-of-war (Physalia)
• Poisonous Animals: Blue bottle, Portuguese man-of-war (Physalia)

Gallery

• 
  Portuguese Man O' War washed ashore at Batemans Bay, New South Wales, Australia; only the air bladder is readily visible
• Portuguese Man O' War washed ashore on Surfer's Paradise, on the Gold Coast in Australia
  Portuguese Man O' War washed ashore on Surfer's Paradise, on the Gold Coast in Australia
• 
  Portuguese Man O' War spotted at Biscayne National Park, Florida
• 
  Portuguese Man O' War washed ashore in Melbourne, Florida