Hydrozoa

Hydrozoa Temporal range: 575–0 Ma PreЄ Є O S D C P T J K Pg N
Siphonophorae
Scientific classification
Kinrick:	Animalia
Phylum:	Cnidaria
Subphylum:	Medusozoa
Cless:	Hydrozoa Owen, 1843
Subclasses and orders
Hydroidolina Anthoathecata Leptothecata Siphonophorae Trachylinae Actinulida Limnomedusae Narcomedusae Trachymedusae

Hydrozoa (hydrozoans, frae auncient Greek ὕδρα, hydra, "sea serpent" an ζῷον, zoon, "animal") are a taxonomic class o indiveedually very smaa, predatory ainimals, some solitary an some colonial, maist livin in saut watter.