Hydractinia
# Hydractinia

Hydractinia Van Beneden, 1841 è un genere di Hydrozoa della famiglia Hydractiniidae.

## Specie

* Hydractinia aculeata
* Hydractinia aggregata (Fraser, 1911)
* Hydractinia allmani
* Hydractinia altispina
* Hydractinia americana (Edwards, 1972)
* Hydractinia angusta
* Hydractinia apicata
* Hydractinia arctica
* Hydractinia areolata
* Hydractinia arge (Clarke, 1882)
* Hydractinia armata (Fraser, 1940)
* Hydractinia australis
* Hydractinia bayeri
* Hydractinia bella
* Hydractinia betkensis
* Hydractinia borealis
* Hydractinia brachyurae
* Hydractinia calderi
* Hydractinia californica (Torrey, 1904)
* Hydractinia canalifera
* Hydractinia carcinicola
* Hydractinia carica (Bergh, 1887)
* Hydractinia carnea (M. Sars, 1846)
* Hydractinia carolinae (Fraser, 1912)
* Hydractinia claviformis
* Hydractinia conchicola
* Hydractinia cryptoconcha
* Hydractinia cryptogonia
* Hydractinia cytaciformis
* Hydractinia dendritica
* Hydractinia diogenes
* Hydractinia disjuncta
* Hydractinia dubia (Mayer, 1900)
* Hydractinia echinata (Fleming, 1828)
* Hydractinia epiconcha
* Hydractinia epispongia
* Hydractinia exigua
* Hydractinia fucicola (M. Sars, 1846)
* Hydractinia granulata
* Hydractinia hancocki
* Hydractinia hayamaensis
* Hydractinia hooperii (Sigerfoos, 1899)
* Hydractinia humilis
* Hydractinia inabai
* Hydractinia inermis
* Hydractinia ingolfi
* Hydractinia kaffaria
* Hydractinia laevispina (Fraser, 1922)
* Hydractinia longispina
* Hydractinia mar
* Hydractinia marsupialia
* Hydractinia meteoris
* Hydractinia milleri (Torrey, 1902)
* Hydractinia minima (Trinci, 1903)
* Hydractinia minoi
* Hydractinia minuta (Mayer, 1900)
* Hydractinia misakinensis
* Hydractinia monocarpa (Allman, 1874)
* Hydractinia monoon
* Hydractinia multigranosi
* Hydractinia multispina (Fraser, 1938)
* Hydractinia multitentaculata
* Hydractinia nassa
* Hydractinia novaezelandiae
* Hydractinia ocellata
* Hydractinia otagoensis
* Hydractinia pacifica
* Hydractinia parvispina (Hartlaub, 1905)
* Hydractinia paucispinata
* Hydractinia piscicola
* Hydractinia polycarpa (Fraser, 1938)
* Hydractinia polyclina (L. Agassiz, 1862)
* Hydractinia polystyla
* Hydractinia proboscidea
* Hydractinia prolifica (Fraser, 1948)
* Hydractinia pruvoti
* Hydractinia quadrigemina
* Hydractinia reticulata
* Hydractinia reticulata
* Hydractinia rubricata
* Hydractinia rugosa
* Hydractinia sarsi
* Hydractinia selena (Mills, 1976)
* Hydractinia serrata
* Hydractinia sodalis
* Hydractinia spinipapillaris
* Hydractinia spiralis
* Hydractinia symbiolongicarpus (Buss & Yund, 1989)
* Hydractinia symbiopollicaris (Buss & Yund, 1989)
* Hydractinia tenuis
* Hydractinia thatcheri
* Hydractinia uchidai
* Hydractinia uniformis
* Hydractinia valens (Fraser, 1941)
* Hydractinia vallini
* Hydractinia yerii
