the man o’ war fish, is playing a dangerous game: It lives among the siphonophore’s tentacles even though it’s not immune to its stings, swimming nimbly between the stingers.

Given that tiny fish make up about 70 to 90 percent of the man o’ war’s diet (it also eats shrimp and other crustaceans), Nomeus gronovii, a.k.a. ZU_09/DigitalVision Vectors/Getty Images Some fish live in them.Ī Portuguese man o’ war in an illustration with other cnidarians. A woman swimming off Sardinia was stung by one and died of what was believed to be anaphylactic shock in 2010. In 1987, one victim suffered a cardiovascular collapse and died after getting too close to a man o’ war in eastern Florida. In 2018, 204 people in Hollywood, Florida, were treated for stings, which can lead to red welts on the skin, muscle cramps, elevated heart rates, and vomiting. But just because deaths are rare doesn’t mean you should touch one. The odds of being killed by a Portuguese man o’ war are slim. Portuguese man o’ war stings can be fatal to humans. When a tentacle is detached from the rest of the colony, it might wash ashore somewhere or drift around for days on end until it decomposes. That’s the maximum length for the dactylozooids-which are normally around 30 feet long and use venom-spewing cells to deliver painful, neurotoxic stings. Stephen Frink/The Image Bank/Getty Images Portuguese man o’ war tentacles can be up to 165 feet long.Īvoid at all costs. It’s also been suggested that Renaissance-era sailors thought the pneumatophores resembled the helmets worn by Portugal’s soldiers during the 16th century. As for the Portuguese part, 19th-century scientists proposed that sailors encountered it near the Portuguese island of Madeira, while modern etymologists tend to think that it looked like the Portuguese version of the ship. Physalia physalias colonies spend a lot of time floating at the water’s surface, and when the gas bladder is expanded, it looks and acts a bit like a sailboat, hence the man o’ war moniker. British sailors took to calling this kind of vessel a “man of war.” In the Age of Sail, many European navies used tall warships loaded with cannons and propelled by the wind.

The name Portuguese man o’ war probably refers to a naval ship. It’s smaller than the Atlantic species and, unlike its bigger counterpart, it hunts with a single, elongated tentacle. It’s sometimes called the Indo-Pacific Portuguese man o’ war and is restricted to the Pacific and Indian oceans. When we say Portuguese man o’ war, we’re talking about Physalia physalis, the siphonophore also known as the Atlantic Portuguese man o’ war, which can be found in warmer parts of Pacific, Caribbean, Indian, and Atlantic waters.Īnother kind of siphonophore that regularly stings beachgoers is the bluebottle, Physalia utriculus. Indo-Pacific bluebottles are close relatives. An expanded float also enables the colony to harness winds to move around.

Capable of expanding or contracting at will, it provides the man o’ war with some buoyancy control. Every man o’ war also has a pneumatophore, or “float”-an overgrown, bag-like polyp which acts as a giant gas bladder and sits at the top of the colony. Dactylozooids are long hunting tentacles built to ensnare prey gastrozooids are smaller tentacles which digest the food and gonozooids are dangling entities whose job is to facilitate reproduction. Though the zooids within a man o’ war are basically clones, they come in different shapes and serve different purposes. They must cooperate as one in order to do things like travel and catch food. These tiny organisms, called polyps or zooids, can’t survive on their own, so they merge together into a tentacled mass. But as it develops, it starts “budding” into distinct structures and organisms. A siphonophore starts out as a fertilized egg. The Portuguese man o’ war may look like a bloated jellyfish, but it’s actually a siphonophore-a bizarre group of animals that consist of colonies made up of dozens, hundreds, or even thousands of genetically identical individual creatures. The Portuguese man o’ war is not a jellyfish. Read on to learn more about these unusual creatures. beaches-which leads to problems for beachgoers. The dangerous Portuguese man o’ war, which has a potentially deadly sting, is often sighted on U.S.

Man of war jellyfish on beach