Class Hydrozoa Owen 1843
Parent taxon: Medusozoa according to E. Kayal et al. 2013
See also Barnes 1998, Sepkoski 2002 and Ulrich 1904
Sister taxa: Auroralumina, Burgessomedusa, Cubozoa, Scyphozoa
Subtaxa: Actinulida Delheidia Fistulella Graptogeitonia Hydrocorallinae Hydroida Hydroidolina Kerunia Lemniscaterina Likinia Limnomedusae Milleporidae Milleporina Narcomedusae Nigriporellidae Plumalina Rhizostromella Roseoporella Siphonophorida Sphaeractinida Spongiomorphida Stoliczkiella Stylasterina Trachylinida Tubulariae Tubuloparietes
Ecology: stationary epifaunal carnivore-suspension feeder