Portuguese man o' war

Physalia physalis · The Portuguese man o' war, also called the bluebottle, is a marine hydrozoan found in the Atlantic, Indian, and Pacific oceans.

Also called Man-of-war, Portuguese man-of-war, Bluebottle, Caravela Portuguesa.

Portuguese man o' war
Photo: Bengt Nyman from Vaxholm, Sweden, CC BY 2.0
Portuguese man o' war
Photo: Taro Taylor aka tarotastic, CC BY 2.0
Portuguese man o' war
Photo: Sylke Rohrlach from Sydney, CC BY-SA 2.0

Taxonomy

KingdomAnimalia
PhylumCnidaria
ClassHydrozoa
OrderSiphonophorae
FamilyPhysaliidae
GenusPhysalia
SpeciesPhysalia physalis

Where it lives

Surface of warm Atlantic, Indian and Pacific waters, often washing onto beaches.

Fun facts

  • It isn't really one animal: it's a colony of many small units called zooids, and every zooid is genetically identical.
  • Its stinging tentacles are usually about 10 m (30 ft) long but can grow to over 30 m (100 ft).
  • Its floating bladder holds mostly air, but up to 13% of the gas inside is carbon monoxide that the animal makes itself.
  • Some are 'left-handed' and some 'right-handed', so the wind pushes them in opposite directions and at most half get blown toward the coast.

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Facts and taxonomy adapted from Wikipedia (CC BY-SA 4.0).