Aeginidae Gegenbaur, 1857 (basis of record)
Aglantha Haeckel, 1879 (additional source)
Aglaopheniidae Marktanner-Turneretscher, 1890 (basis of record)
Amphisbetia L. Agassiz, 1862 (additional source)
Anthoathecata (basis of record)
Bougainvillia Lesson, 1830 (additional source)
Bougainvilliidae Lütken, 1850 (basis of record)
Campanulariidae Johnston, 1836 (basis of record)
Capitata (basis of record)
Clytia Lamouroux, 1812 (additional source)
Clytia gracilis (M. Sars, 1851) (additional source)
Clytia hemisphaerica (Linnaeus, 1767) (additional source)
Conica accepted as Leptothecata (basis of record)
Corymorpha M. Sars, 1835 (additional source)
Corymorphidae Allman, 1872 (basis of record)
Corynidae Johnston, 1836 (basis of record)
Cosmetira Forbes, 1848 (additional source)
Dipleurosomatidae Boeck, 1868 (basis of record)
Ectopleura L. Agassiz, 1862 (additional source)
Eirenidae Haeckel, 1879 (basis of record)
Eutima McCrady, 1859 (additional source)
Filifera (basis of record)
Geryoniidae Eschscholtz, 1829 (basis of record)
Gymnangium Hincks, 1874 (additional source)
Haleciidae Hincks, 1868 (basis of record)
Hybocodon L. Agassiz, 1860 (additional source)
Hydractinia Van Beneden, 1844 (additional source)
Hydractiniidae L. Agassiz, 1862 (basis of record)
Hydrichthys Fewkes, 1887 (additional source)
Hydroidolina (basis of record)
Lafoeidae Hincks, 1868 (basis of record)
Laodicea Lesson, 1843 (additional source)
Laodicea undulata (Forbes & Goodsir, 1853) (additional source)
Laodiceidae Agassiz, 1862 (basis of record)
Leptothecata (basis of record)
Leuckartiara Hartlaub, 1914 (additional source)
Leuckartiara octona (Fleming, 1823) (additional source)
Limnomedusae (basis of record)
Lovenella Hincks, 1868 (additional source)
Margelopsidae Mayer, 1910 (basis of record)
Margelopsis Hartlaub, 1897 (additional source)
Melicertidae Agassiz, 1862 (basis of record)
Mitrocomella polydiademata (Romanes, 1876) (additional source)
Mitrocomidae Haeckel, 1879 (basis of record)
Modeeria Forbes, 1848 (additional source)
Narcomedusae (basis of record)
Obelia Péron & Lesueur, 1810 (additional source)
Obelia dichotoma (Linnaeus, 1758) (additional source)
Obelia geniculata (Linnaeus, 1758) (additional source)
Obelia longissima (Pallas, 1766) (additional source)
Olindiasidae Haeckel, 1879 accepted as Olindiidae Haeckel, 1879 (basis of record)
Orchistomatidae Bouillon, 1984 (basis of record)
Orthopyxis L. Agassiz, 1862 (additional source)
Orthopyxis integra (MacGillivray, 1842) (additional source)
Phialella Browne, 1902 (additional source)
Phialellidae Russell, 1953 (basis of record)
Porpita porpita (Linnaeus, 1758) (additional source)
Porpitidae Goldfuss, 1818 (basis of record)
Proboscidactyla Brandt, 1835 (additional source)
Proboscidactylidae Hand & Hendrickson, 1950 (basis of record)
Proboscoida accepted as Leptothecata (basis of record)
Ptychogastriidae Mayer, 1910 (basis of record)
Rathkea Brandt, 1837 (additional source)
Rathkea octopunctata (M. Sars, 1835) (additional source)
Rathkeidae Russell, 1953 (basis of record)
Rhopalonematidae Russell, 1953 (basis of record)
Sarsia Lesson, 1843 (additional source)
Sertularia Linnaeus, 1758 (additional source)
Sertularia marginata (Kirchenpauer, 1864) accepted as Tridentata marginata (Kirchenpauer, 1864) (additional source)
Sertulariidae Lamouroux, 1812 (basis of record)
Tiarannidae Russell, 1940 (basis of record)
Tiaropsidae Boero, Bouillon & Danovaro, 1987 (basis of record)
Trachylinae (basis of record)
Trachymedusae (basis of record)
Tubulariidae Goldfuss, 1818 (basis of record)
Velella Lamarck, 1801 (additional source)
Velella velella (Linnaeus, 1758) (additional source)
Zancleidae Russell, 1953 (basis of record)

Europe for Olindiasidae Haeckel, 1879 

 additional information

 for Nemertesia antennina (Linnaeus, 1758)

Allman (1871) reported reduced medusoids in Nemertesia antennina (L. 1758), but this observation has not been ... [details]

 Authority

 for Monotheca obliqua (Johnston, 1847)

(Saunders in Johnston, 1847) [details]

 Authority

 for Sertularia marginata (Kirchenpauer, 1864)

Kirchenpauer, 1864 [details]

 Ecology

 for Hydrichthys cyclothonis Damas, 1934

complete cycle unknown? [details]

 Synonymy

 for Bougainvillia flavida Hartlaub, 1897

Synonymised with Bougainvillia britannica (Forbes, 1841) [details]