1. Family Bougainvilliidae Lütken, 1850
2. Family Cordylophoridae von Lendenfeld, 1885
3. Family Cytaeididae L. Agassiz, 1862
4. Family Eudendriidae L. Agassiz, 1862
5. Family Heterotentaculidae Schuchert, 2010
6. Family Hydractiniidae L. Agassiz, 1862
7. Family Magapiidae Schuchert & Bouillon, 2009
8. Family Oceaniidae Eschscholtz, 1829
9. Family Pandeidae Haeckel, 1879
10. Family Protiaridae Haeckel, 1879
11. Family Trichydridae Hincks, 1868
12. Family Russelliidae Kramp, 1957 accepted as Heterotentaculidae Schuchert, 2010 (invalid name)

marine, brackish, fresh, terrestrial

recent + fossil

Kühn, A., 1913. Entwicklungsgeschichte und Verwandschaftsbeziehungen der Hydrozoen. I. Teil: Die Hydroiden. Erg. Fortschr. Zool. 4 1-2: 1-284. [details] 

WRiMS (2024). Filifera. Accessed at: https://marinespecies.org/introduced./aphia.php?p=taxdetails&id=16352 on 2025-04-04

Costello, M. J.; Ahyong, S.; Bieler, R.; Boudouresque, C.; Desiderato, A.; Downey, R.; Galil, B. S.; Gollasch, S.; Hutchings, P.; Kamburska, L.; Katsanevakis, S.; Kupriyanova, E.; Lejeusne, C.; Ma, K. C. K.; Marchini, A.; Occhipinti, A.; Pagad, S.; Pino, L.; Poore, G. C. B.; Rewicz, T.; Rius, M.; Robinson, T. B.; Sobczyk, R.; Stępień, A.; Turon, X.; Valls Domedel, G.; Verleye, T.; Vieira, L. M.; Willan, R. C.; Zhan, A. (2025). World Register of Introduced Marine Species (WRiMS). Filifera. Accessed at: https://marinespecies.org/introduced%20/aphia.php?p=taxdetails&id=16352 on 2025-04-04

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