| Scientific Name | Author | English Name |
|---|---|---|
| Agglutinaria operculata | Antsulevich, 1987 | |
| Anarthroclada parmata | Naumov, 1955 | |
| Antennella africana | Broch, 1914 | |
| Antennella allmani | Armstrong, 1879 | |
| Antennella avalonia | Torrey, 1902 | |
| Antennella biarmata | Nutting, 1927 | |
| Antennella billardi | Galea, 2021 | |
| Antennella compacta | Fraser, 1938 | |
| Antennella curvitheca | Fraser, 1937 | |
| Antennella kiwiana | Schuchert, 1997 | |
| Antennella megatheca | Ansín Agís, Vervoort, & Ramil, 2009 | |
| Antennella microscopica | (Mulder & Trebilcock, 1909) | |
| Antennella quadriaurita | Ritchie, 1909 | |
| Antennella recta | Nutting, 1927 | |
| Antennella secundaria | (Gmelin, 1791) | Sessile hydrozoans |
| Antennella siliquosa | (Hincks) | |
| Antennella sinuosa | Ansín Agís, Vervoort, & Ramil, 2009 | |
| Antennella tubulosa | (Bale, 1894) | |
| Antennella varians | (Billard, 1911) | |
| Anthohebella brevitheca | (Leloup, 1938) | |
| Anthohebella darwinensis | Watson, 2000 | |
| Anthohebella najimaensis | (Hirohito, 1995) | |
| Anthohebella parasitica | (Ciamician, 1880) | |
| Anthohebella tubitheca | (Millard & Bouillon, 1975) | |
| Astrolabia furcata | (Fraser, 1937) | |
| Billardia hyalina | Vervoort & Watson, 2003 | |
| Billardia intermedia | Blanco, 1967 | |
| Callicarpa gracilis | Fewkes, 1881 | |
| Calvinia mirabilis | Nutting, 1900 | |
| Campalecium alcoicum | Watson, 1993 | |
| Corhiza bellicosa | Millard, 1962 | |
| Corhiza complexa | (Nutting, 1905) | |
| Corhiza fascicularis | (Allman, 1883) | |
| Corhiza pannosa | Millard, 1962 | |
| Corhiza patula | Galea, 2020 | |
| Corhiza scotiae | (Ritchie, 1907) | |
| Corhiza sociabilis | Millard, 1980 | |
| Corhiza splendens | Vervoort & Watson, 2003 | |
| Corhiza suensoni | (Jäderholm, 1896) | |
| Cryptolaria rigida | (Fraser, 1940) | |
| Cryptolaria spinosa | Millard, 1980 | |
| Dentitheca bidentata | (Jäderholm, 1920) | |
| Dentitheca hertwigi | (Stechow, 1909) | |
| Diplopteroides grandis | (Nutting, 1900) | |
| Diplopteroides longipinna | (Nutting, 1900) | |
| Eucheilota birabeni | Tundisi, 1962 | |
| Filellum adhaerens | (Nutting, 1901) | |
| Filellum parasiticum | (Antsulevich, 1987) | |
| Foersteria bruuni | (Navas, 1969) | |
| Gattya aglaopheniaformis | (Mulder & Trebilcock, 1909) | |
| Gattya balei | (Bartlett, 1907) | |
| Gattya conspecta | (Billard, 1907) | |
| Gattya heurteli | (Billard, 1907) | |
| Gattya humilis | Allman, 1886 | |
| Gattya multithecata | (Jarvis, 1922) | |
| Gattya trebilcocki | Watson, 1973 | |
| Gattya tropicalis | Millard & Bouillon, 1973 | |
| Gattya wimleni | Gravier-Bonnet, 1998 | |
| Halopteris constricta | Totton, 1930 | |
| Halopteris crassa | (Billard, 1911) | |
| Halopteris diaphana | (Heller, 1868) | |
| Halopteris enersis | Galea, 2006 | Enersis hydroid |
| Halopteris everta | (Mulder & Trebilcock, 1909) | |
| Halopteris gemellipara | Millard, 1962 | |
| Halopteris geminata | (Allman, 1877) | |
| Halopteris glutinosa | (Lamouroux, 1816) | |
| Halopteris gracilis | (Clarke, 1879) | |
| Halopteris alternata | (Nutting, 1900) | |
| Halopteris australis | Galea, 2018 | |
| Halopteris billardi | (Vannucci, 1951) | |
| Halopteris brasiliensis | Galea, 2018 | |
| Halopteris carinata | Allman, 1877 | |
| Halopteris catharina | (Johnson, 1833) | |
| Halopteris clarkei | (Nutting, 1900) | |
| Halopteris concava | (Billard, 1911) | |
| Halopteris jedani | (Billard, 1913) | |
| Halopteris liechtensternii | (Marktanner-Turneretscher, 1890) | |
| Halopteris opposita | (Mulder & Trebilcock, 1911) | |
| Halopteris peculiaris | (Billard, 1913) | |
| Halopteris plagiocampa | (Pictet, 1893) | |
| Halopteris platygonotheca | Schuchert, 1997 | |
| Halopteris prominens | Vervoort & Watson, 2003 | |
| Halopteris pseudoconstricta | Millard, 1975 | |
| Halopteris regressa | (Billard, 1918) | |
| Halopteris rostrata | Millard, 1975 | |
| Halopteris schucherti | Galea, 2006 | Schuchert's hydroid |
| Halopteris simplex | (Warren, 1914) | |
| Halopteris tenella | (Verrill, 1874) | Plume hydroid |
| Halopteris tuba | (Kirchenpauer, 1876) | |
| Halopteris valdiviae | (Stechow, 1923) | |
| Halopteris violae | Calder, Mallinson, Collins & Hickman, 2003 | |
| Halopteris zygocladia | (Bale, 1914) | |
| Hippurella elegans | Fraser, 1937 | |
| Hydranthea aloysii | (Zoja, 1893) | |
| Hydranthea margarica | (Hincks, 1862) | |
| Hydranthea phialiformis | Antsulevich, 1983 | |
| Lafoea weddelli | Blanco, 1991 | |
| Lineolaria flexuosa | Bale, 1884 | |
| Lineolaria spinulosa | Hincks, 1861 | |
| Malagazzia condensum | (Kramp, 1953) | |
| Malagazzia multitentaculatum | (Menon, 1932) | |
| Melicertissa platygastra | Nair, 1951 | |
| Monostaechas faurei | Millard, 1958 | |
| Monostaechas fisheri | Nutting, 1905 | |
| Monostaechas natalensis | Millard, 1958 | |
| Monostaechas quadridens | (Mccrady, 1859) | |
| Monostaechas sibogae | Billard, 1913 | |
| Nuditheca dallii | (Clark, 1877) | |
| Oswaldella bifurca | (Hartlaub, 1904) | |
| Oswaldella crassa | Peña-Cantero & Vervoort, 1998 | |
| Oswaldella curiosa | Peña-Cantero & Vervoort, 1998 | |
| Oswaldella delicata | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella encarnae | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella garciacarrascosai | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella gracilis | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella incognita | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella obscura | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella rigida | Peña-Cantero, Svoboda & Vervoort, 1997 | |
| Oswaldella terranovae | Peña-Cantero & Vervoort, 1996 | |
| Polyplumaria arenaria | Antsulevich, 1997 | |
| Polyplumaria cornuta | (Bale, 1884) | |
| Polyplumaria flabellata | (Sars, 1873) | |
| Polyplumaria gracilis | (Naumov, 1960) | |
| Polyplumaria gracillima | (Sars, 1873) | |
| Polyplumaria kossowskae | (Billard, 1911) | |
| Polyplumaria sibogae | Billard, 1913 | |
| Pseudoplumaria marocana | (Billard, 1930) | |
| Pseudoplumaria sabinae | Ramil & Vervoort, 1992 | |
| Scandia michaelsarsi | (Leloup, 1935) | |
| Scandia minor | (Fraser, 1938) | |
| Schizotricha dichotoma | Nutting, 1900 | |
| Schizotricha falcata | Peña-Cantero, 1998 | |
| Schizotricha glacialis | (Hickson & Gravely, 1907) | |
| Schizotricha nana | Peña-Cantero, Svoboda & Vervoort, 1996 | |
| Schizotricha profunda | (Nutting, 1900) | |
| Schizotricha turqueti | Billard, 1906 | |
| Schizotricha vervoorti | Peña-Cantero, 1998 | |
| Sibogella erecta | Billard, 1911 | |
| Tetracanna octonema | Goy, 1979 | |
| Wuvula ochracea | (Mayer, 1910) |