Traits Taxon list
Hydra baikalensis Swarczewsky, 1923
Hydra beijingensis Fan, 2003
Hydra canadensis Rowan, 1930
Hydra cauliculata Hyman, 1938
Hydra cereus (Ellis & Solander, 1786) (uncertain > unassessed )
Hydra circumcincta Schulze, 1914
Hydra corolliflora Gaertner, 1762 (uncertain > unassessed )
Hydra daqingensis Fan, 2000
Hydra doliolum (Pallas, 1766) accepted as Actinia doliolum Pallas, 1766 accepted as Pentacta doliolum (Pallas, 1766)
Hydra ethiopiae Hickson, 1930
Hydra gemmacea (Ellis & Solander, 1786) accepted as Actinia gemmacea Ellis & Solander, 1786 accepted as Aulactinia verrucosa (Pennant, 1777) accepted as Bunodactis verrucosa (Pennant, 1777)
Hydra hadleyi (Forrest, 1959)
Hydra harbinensis Fan & Shi, 2003
Hydra Helianthus (Ellis, 1768) accepted as Actinia helianthus Ellis, 1768 accepted as Stichodactyla helianthus (Ellis, 1768)
Hydra hymanae Hadley & Forrest, 1949
Hydra iheringi Cordero, 1939
Hydra intaba Ewer, 1948
Hydra intermedia De Carvalho Wolle, 1978
Hydra japonica Itô, 1947
Hydra javanica Schulze, 1927
Hydra liriosoma Campbell, 1987
Hydra madagascariensis Campbell, 1999
Hydra magellanica Schulze, 1927
Hydra mariana Cox & Young, 1973
Hydra mesembryanthemum (Ellis & Solander, 1786) accepted as Actinia mesembryanthemum Ellis & Solander, 1786 accepted as Actinia nigropunctata den Hartog & Ocaña, 2003
Hydra minima Forrest, 1963
Hydra mohensis Fan & Shi, 1999
Hydra oligactis Pallas, 1766
Hydra oregona Griffin & Peters, 1939
Hydra oxycnida Schulze, 1914
Hydra paludicola Itô, 1947
Hydra paranensis Cernosvitov, 1935
Hydra parva Itô, 1947
Hydra plagiodesmica Dioni, 1968
Hydra polymorpha Chen & Wang, 2008
Hydra robusta (Itô, 1947)
Hydra rutgersensis Forrest, 1963
Hydra salmacidis Lang da Silveira, Souza-Gomes & de Souza e Silva, 1997
Hydra sinensis Wang, Deng, Lai & Li, 2009
Hydra sociata (Ellis, 1768) accepted as Actinia sociata Ellis, 1768 accepted as Zoanthus sociatus (Ellis, 1768)
Hydra thomseni Cordero, 1941
Hydra umfula Ewer, 1948
Hydra utahensis Hyman, 1931
Hydra viridissima Pallas, 1766
Hydra vulgaris Pallas, 1766
Hydra zeylandica Burt, 1929
Hydra zhujiangensis Liu & Wang, 2010