Superregnum:Eukaryota
Cladus:Unikonta
Cladus:Opisthokonta
Cladus:Holozoa
Regnum:Animalia
Subregnum:Eumetazoa
Cladus:ParaHoxozoa
Phylum:Cnidaria
Classis:Hydrozoa
Subclasses (2):Hydroidolina -Trachylinae

Unplaced genera:Protulophila

• Altuna, Á. 2012. New records of bathyal Leptolida (Cnidaria: Hydrozoa: Leptothecata) from the Bay of Biscay and the northwestern Iberian Peninsula (northeastern Atlantic).Zootaxa 3565: 1–17.PreviewReference page. 
• Àngel, J.J.S. &Cantero, A.L.P. 2019. Benthic hydroids (Cnidaria, Hydrozoa) from the Weddell Sea (Antarctica).Zootaxa 4570(1): 1–78.DOI:10.11646/zootaxa.4570.1.1Reference page. 
• Bouillon, J.;Barnett, T.J. 1999. The marine fauna of New Zealand: Hydromedusae (Cnidaria: Hydrozoa).NIWA biodiversity memoir, (113)
• Calder, D.R. 2010. Some anthoathecate hydroids and limnopolyps (Cnidaria, Hydrozoa) from the Hawaiian archipelago.Zootaxa 2590: 1–91.PreviewPDF
• Calder, D.R. 2013. Some shallow-water hydroids (Cnidaria: Hydrozoa) from the central east coast of Florida, USA.Zootaxa 3648(1): 1–72.DOI:10.11646/zootaxa.3648.1.1Reference page. 
• Calder, D.R. 2020. Some leptothecate hydroids (Cnidaria, Hydrozoa) from Hawaii, mostly from inshore and nearshore waters.Zootaxa 4830(2): 201–246.DOI:10.11646/zootaxa.4830.2.1pdfReference page. 
• Galea, H.R. 2010. Notes on a small collection of thecate hydroids (Cnidaria: Hydrozoa) from Tristan da Cunha, south Atlantic.Zootaxa 2336: 1–18.Preview
• Galea, H.R. 2013. New additions to the shallow-water hydroids (Cnidaria: Hydrozoa) of the French Lesser Antilles: Martinique.Zootaxa 3686(1): 1–50.DOI:10.11646/zootaxa.3686.1.1Reference page. 
• Galea, H.R.,Ferry, R. &Bertot, J.-M. 2012. Medusoids in the life cycle ofDentitheca dendritica (Nutting, 1900) andNemalecium gracile sp. nov. (Cnidaria: Hydrozoa).Zootaxa 3527: 43–54.PreviewReference page. 
• Galea, H.R. &Schories, D. 2012: Some hydrozoans (Cnidaria) from Central Chile and the Strait of Magellan.Zootaxa 3296(1): 19–67.DOI:10.11646/zootaxa.3296.1.2.ResearchGate.Reference page. 
• Galea, H.R. &Schories, D. 2012. Some hydrozoans (Cnidaria) from King George Island, Antarctica.Zootaxa 3321: 1–21.PreviewReference page. 
• Gravili, C.,Pavesi, L.,Boero, F. &Tendal, O.S. 2018. A review of Paul Lassenius Kramp’s hydrozoan types (taxonomic status, location and condition of the material) and a biography of the Danish zoologist.Zootaxa 4407(1): 65–85.DOI:10.11646/zootaxa.4407.1.4Reference page. 
• Humara-Gil, K.J. &Cruz-Gómez, C. 2018. New records of benthic hydroids (Cnidaria: Hydrozoa) from the coast of Oaxaca, Mexico.Zootaxa 4455(3): 454–470.DOI:10.11646/zootaxa.4455.3.3Reference page. 
• Miranda, T.P.,Cunha, A.F. &Marques, A.C. 2016. Status of the names of some hydroid species (Cnidaria, Hydrozoa), described from the Atlantic coast of Patagonia.Zootaxa 4171(3): 595–600.DOI:10.11646/zootaxa.4171.3.13.Reference page. 
• Miranda, T.P.,Genzano, G.N. &Marques, A.C. 2015. Areas of endemism in the Southwestern Atlantic Ocean based on the distribution of benthic hydroids (Cnidaria: Hydrozoa).Zootaxa 4033(4): 484–506.DOI:10.11646/zootaxa.4033.4.2Preview (PDF).Reference page. 
• Montgomery, A.D.,Fenner, D. &Toonen, R.J. 2019. Annotated checklist for stony corals of American Sāmoa with reference to mesophotic depth records.Zookeys, 849: 1–170.DOI:10.3897/zookeys.849.34763Reference page. 
• Moura, C.J. 2015: The hydrozoan fauna (Cnidaria: Hydrozoa) from the peaks of the Ormonde and Gettysburg seamounts (Gorringe Bank, NE Atlantic).Zootaxa 3972(2): 148–180.DOI:10.11646/zootaxa.3972.2.2.Preview (PDF)Reference page. 
• Peña Cantero, A.L. 2015: Review of some little-known benthic hydroids (Cnidaria, Hydrozoa) from the Southern Ocean.Zootaxa 3972(3): 369–392.DOI:10.11646/zootaxa.3972.3.4.Preview (PDF)Reference page. 
• Peña Cantero, A.L. &Horton, T. 2017. Benthic hydroids (Cnidaria, Hydrozoa) from bathyal and abyssal depths of the Northeast Atlantic held in the modernDiscovery Collections.Zootaxa 4347(1): 1–30.DOI:10.11646/zootaxa.4347.1.1.Reference page. 
• Schuchert, P. 1996. The marine fauna of New Zealand: athecate hydroids and their medusae (Cnidaria, Hydrozoa).NIWA biodiversity memoir, (106).
• Torres-Rodríguez, J.,Ortiz-Oyola, D.,Puentes-Sayo, A.,Lecompte, O.P. &Jauregui, A. 2020. Genetic and morphologic identities of hydrozoans (Cnidaria, Hydrozoa) from reef patches of Santa Marta, Colombian Caribbean.Zootaxa 4758(1): 127–140.DOI:10.11646/zootaxa.4758.1.5Reference page. 
• Vervoort, W. &Watson, J.E. 2003. The marine fauna of New Zealand: Leptothecata (Cnidaria: Hydrozoa) (thecate hydroids).NIWA biodiversity memoir, (119).
• ITIS
• Watson, J.E. 2011. New species, new records and redescriptions of thecate hydroids (Cnidaria: Hydrozoa: Leptothecata) from southern Australia.Zootaxa 3122: 1–36.Preview

• Hydrozoa in theWorld Hydrozoa Database

For more multimedia, look atHydrozoa onWikimedia Commons.

• Pages with taxonavigation templates
• Pages with vernacular names