Porpita porpita

Porpita porpita, or the blue button, is a marine organism consisting of a colony of hydroids found in the warmer, tropical and sub-tropical waters of the Pacific, Atlantic, and Indian oceans, as well as the Mediterranean Sea and eastern Arabian Sea. It was first identified by Carl Linnaeus in 1758, under the basionym Medusa porpita. In addition, it is one of the two genera under the suborder Chondrophora, which is a group of cnidarians that also includes Velella. The chondrophores are similar to the better-known siphonophores, which includes the Portuguese man o' war, or Physalia physalis. Although it is superficially similar to a jellyfish, each apparent individual is actually a colony of hydrozoan polyps. The taxonomic class, Hydrozoa, falls under the phylum Cnidaria, which includes anemones, corals, and jellyfish, which explains their similar appearances.