Hydrozoa

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Kingdom: Animalia
Subregnum: Eumetazoa
Cladus: ParaHoxozoa
Phylum: Cnidaria
Classis:
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. Preview Reference 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.4570.1.1 Reference 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. Preview PDF
• 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.3648.1.1 Reference 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.4830.2.1 pdf Reference 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.3686.1.1 Reference page. 
• Galea, H.R., Ferry, R. & Bertot, J.-M. 2012. Medusoids in the life cycle of Dentitheca dendritica (Nutting, 1900) and Nemalecium gracile sp. nov. (Cnidaria: Hydrozoa). Zootaxa 3527: 43–54. Preview Reference 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. Preview Reference page. 
• Gil, M., Ramil, F. & Agís, J.A. 2020. Hydroids (Cnidaria, Hydrozoa) from Mauritanian Coral Mounds. Zootaxa 4878(3): 412–466. DOI: 10.11646/zootaxa.4878.3.2 Reference 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.4407.1.4 Reference 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.4455.3.3 Reference 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.4033.4.2 Preview (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.849.34763 . Reference 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 modern Discovery 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.4758.1.5 Reference 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 the World Hydrozoa Database

For more multimedia, look at Hydrozoa on Wikimedia Commons.