Physalia

Physalia
Physalia physalis, the Atlantic Portuguese man o' war
Scientific classification
Kingdom: Animalia
Phylum: Cnidaria
Class: Hydrozoa
Order: Siphonophorae
Suborder: Cystonectae
Family: Physaliidae
Brandt, 1835
Genus: Physalia
Lamarck, 1801
Type species
Physalia physalis
(Linnaeus, 1758)
Species
Synonyms
  • Family-level synonym
    • Physalidae Brandt, 1835 (original spelling)

Physalia is a genus of hydrozoan cnidarians within the monotypic family Physaliidae, commonly known as man o' wars or bluebottles. They are siphonophores, colonial organisms composed of specialized individual zooids that function together as a single unit. Unlike most siphonophores, which are planktonic, Physalia species are neustonic, living at the ocean-air interface.