Abothrium Van Beneden, 1870 (additional source)
Abothrium gadi Van Beneden, 1870 (additional source)
Abylopsis tetragona (Otto, 1823) (additional source)
Acanthocephaloides Meyer, 1932 (additional source)
Acanthocephaloides distinctus Golvan, 1969 (additional source)
Acanthocephaloides geneticus Buron, Renaud & Euzet, 1985 (additional source)
Acanthocephaloides incrassatus (Molin, 1858) Meyer, 1932 accepted as Paracanthocephaloides incrassatus (Molin, 1858) Bray, Spencer Jones & Lewis, 1988 (additional source)
Acanthocephaloides propinquus (Dujardin, 1845) Meyer, 1933 accepted as Solearhynchus rhytidotes (Monticelli, 1905) Belofastova, 2006 (additional source)
Acanthocephalus anguillae (Müller, 1780) Lühe, 1911 (additional source)
Acanthocephalus clavula (Dujardin, 1845) Grabda-Kazubska & Chubb, 1968 (additional source)
Acanthocephalus lucii (Müller, 1776) Lühe, 1911 (additional source)
Acanthochondria Oakley, 1930 (additional source)
Acanthogyrus lizae Orecchia, Paggi & Radujkovic, 1988 accepted as Acanthogyrus (Acanthosentis) adriaticus Amin, 2005 (additional source)
Acanthonotozomatidae Stebbing, 1906 (additional source)
Acidostoma Lilljeborg, 1865 (additional source)
Acidostoma nodiferum Stephensen, 1923 accepted as Acidostoma obesum (Spence Bate & Westwood, 1861) (additional source)
Acrenhydrosoma perplexum (Scott T., 1899) (additional source)
Aeginina Norman, 1905 (additional source)
Agalma Eschscholtz, 1825 (additional source)
Allomelita Stock, 1984 (additional source)
Amathillopsidae Pirlot, 1934 (additional source)
Ampelisca laevigata Liljeborg, 1856 accepted as Ampelisca brevicornis (A. Costa, 1853) (additional source)
Ampelisca odontoplax G. O. Sars, 1879 (additional source)
Ampeliscidae Krøyer, 1842 (additional source)
Amphilochidae Boeck, 1871 (additional source)
Amphilochus Spence Bate, 1863 (additional source)
Amphinema dinema (Péron & Lesueur, 1810) (additional source)
Amphithopsis Boeck, 1861 (additional source)
Amphithopsis longicaudata Boeck, 1861 (additional source)
Ampithoidae Boeck, 1871 (additional source)
Ancorabolus mirabilis Norman, 1903 (additional source)
Andaniopsis G.O. Sars, 1891 (additional source)
Andaniopsis nordlandica (Boeck, 1871) (additional source)
Andracantha phalacrocoracis (Yamaguti, 1939) Schmidt, 1975 (additional source)
Andracantha tunitae (Weiss, 1914) Zdzitowiecki, 1989 (additional source)
Anisogammaridae Bousfield, 1977 (additional source)
Anthobothrium Van Beneden, 1850 (additional source)
Anthobothrium cornucopia Van Beneden, 1850 (additional source)
Aoridae Stebbing, 1899 (additional source)
Apherusa Walker, 1891 (additional source)
Apolemia Eschscholtz, 1829 (additional source)
Apolemia uvaria (Lesueur, 1815) (additional source)
Archaeobalaninae Newman & Ross, 1976 (additional source)
Argestes mollis Sars G.O., 1910 (additional source)
Argissa Boeck, 1871 (additional source)
Argissidae Walker, 1904 (additional source)
Arhythmorhynchus longicollis (Villot, 1875) Lühe, 1912 (additional source)
Aricidea laubieri Hartley, 1981 represented as Aricidea (Acmira) laubieri Hartley, 1981 (additional source)
Aricidea roberti Hartley, 1983 represented as Aricidea (Strelzovia) roberti Hartley, 1984 (additional source)
Artotrogidae Brady, 1880 (additional source)
Artotrogus Boeck, 1860 (additional source)
Ascidia obliqua Alder, 1863 (additional source)
Ascidia virginea Müller, 1776 (additional source)
Ascothoracida (additional source)
Aslia lefevrei (Barrois, 1882) (additional source)
Aspersentis johni (Baylis, 1929) Chandler, 1934 (additional source)
Asterope mariae (Baird, 1850) accepted as Cylindroleberis mariae (Baird, 1850) (additional source)
Astyra Boeck, 1871 (additional source)
Astyra abyssi Boeck, 1871 (additional source)
Astyridae Pirlot, 1934 accepted as Astyrinae Pirlot, 1934 (additional source)
Atylus nordlandicus Boeck, 1871 accepted as Nototropis nordlandicus (Boeck, 1871) (additional source)
Augeneria tentaculata Monro, 1930 (additional source)
Balanus hameri (Ascanius) accepted as Chirona hameri (Ascanius, 1767) (additional source)
Bassia L. Agassiz, 1862 (additional source)
Bassia bassensis (Quoy & Gaimard, 1833) (additional source)
Bathymedon longimanus (Boeck, 1871) (additional source)
Bathymedon obtusifrons (Hansen, 1883) (additional source)
Bathymedon saussurei (Boeck, 1871) (additional source)
Biancolinidae J.L. Barnard, 1972 accepted as Ampithoidae Boeck, 1871 (additional source)
Bimeria Wright, 1859 (additional source)
Bogidiellidae Hertzog, 1936 (additional source)
Bolbosoma capitatum (von Linstow, 1880) Porta, 1908 (additional source)
Bolbosoma physeteris Gubanov, 1952 accepted as Bolbosoma capitatum (von Linstow, 1880) Porta, 1908 (additional source)
Bolbosoma vasculosum (Rudolphi, 1819) Porta, 1908 (additional source)
Bomolochidae Claus, 1875 (additional source)
Bomolochus Nordmann, 1832 (additional source)
Brachiella Cuvier, 1830 (additional source)
Bradya (Bradya) scotti Sars G.O., 1920 represented as Bradya scotti Sars G.O., 1920 (additional source)
Breizacanthus chabaudi Golvan, 1969 (additional source)
Breizacanthus golvani Gaevskaja & Shukhgalter, 1984 (additional source)
Breizacanthus irenae Golvan, 1969 (additional source)
Breizacanthus ligur Paggi, Orecchia & Della Seta, 1975 (additional source)
Bruzelia typica Boeck, 1871 (additional source)
Byblis crassicornis Metzger, 1875 (additional source)
Byblis guernei Chevreux, 1887 (additional source)
Caeconyx Barnard & Karaman, 1991 (additional source)
Caligidae Burmeister, 1835 (additional source)
Caligus Müller O.F., 1785 (additional source)
Calliobothrium Van Beneden, 1850 (additional source)
Calliobothrium leuckarti Van Beneden, 1850 accepted as Symcallio leuckarti (van Beneden, 1850) Bernot, Caira & Pickering, 2015 (additional source)
Callisoma A. Costa in Hope, 1851 accepted as Scopelocheirus Spence Bate, 1857 (additional source)
Campanularia hincksii Alder, 1856 (additional source)
Campylaspis horridoides Stephensen, 1915 (additional source)
Campylaspis rostrata Calman, 1905 (additional source)
Campylaspis squamifera Fage, 1929 (additional source)
Campylaspis undata Sars, 1864 (additional source)
Cancerilla Dalyell, 1851 (additional source)
Cancerillidae Giesbrecht, 1897 (additional source)
Caprella Lamarck, 1801 (additional source)
Caprella ciliata G.O. Sars, 1883 (additional source)