Abditodentrix Patterson, 1985 (additional source)
Abothrium Van Beneden, 1870 (basis of record)
Abudefduf Forsskål, 1775 (additional source)
Abyssascidia Herdman, 1880 (additional source)
Acaenomolgus Humes & Stock, 1972 (additional source)
Acanella Gray, 1870 (additional source)
Acanthephyra A. Milne-Edwards, 1881 (additional source)
Acanthobothrium Blanchard, 1848 (additional source)
Acanthocaris Sim, 1872 accepted as Gastrosaccus Norman, 1868 (additional source)
Acanthocarpus Stimpson, 1871 (additional source)
Acanthochaenus Gill, 1884 (additional source)
Acanthochondrites Oakley, 1930 (additional source)
Acanthocope Beddard, 1885 (additional source)
Acanthocorbis S.Hara & E.Takahashi, 1984 (additional source)
Acanthocotyle Monticelli, 1888 (additional source)
Acanthocybium Gill, 1862 (additional source)
Acanthocythereis Howe, 1963 (additional source)
Acanthoeca W.N.Ellis, 1930 (additional source)
Acanthoecopsis Norris, 1965 (additional source)
Acanthogorgia Gray, 1857 (additional source)
Acantholaimus Allgén, 1933 (additional source)
Acanthomacrostomum Papi & Swedmark, 1959 (additional source)
Acanthomunna Beddard, 1886 (additional source)
Acanthonchus Cobb, 1920 (additional source)
Acanthonotus Ross, 1835 accepted as Acanthonotozoma Boeck, 1876 (additional source)
Acanthonyx Latreille, 1828 (additional source)
Acanthopharyngoides Chitwood, 1936 (additional source)
Acanthopharynx Marion, 1870 (additional source)
Acanthoscina Vosseler, 1900 (additional source)
Acanthostepheia Boeck, 1871 (additional source)
Acanthostomum Looss, 1899 (additional source)
Acanthostracion Bleeker, 1865 (additional source)
Acanthozone Boeck, 1871 accepted as Paramphithoe Bruzelius, 1859 (additional source)
Acasta Leach, 1817 (additional source)
Acaulis Stimpson, 1853 (additional source)
Acauloides Bouillon, 1965 (additional source)
Accacladocoelium Odhner, 1928 (additional source)
Accacoelium Monticelli, 1893 (additional source)
Accipiter Brisson, 1760 (basis of record)
Aceroides G.O. Sars, 1892 (additional source)
Acerotisa Strand, 1928 (additional source)
Acestoplana Faubel, 1983 (additional source)
Acetabulastoma Schornikov, 1970 (additional source)
Achelia Hodge, 1864 (additional source)
Achelous De Haan, 1833 (additional source)
Acineta Ehrenberg, 1834 (additional source)
Acinetoides Plate, 1888 accepted as Hypocoma Gruber, 1884 (additional source)
Acmostomum Schmarda, 1859 (additional source)
Acrocalanus Giesbrecht, 1888 (additional source)
Acrocirrus Grube, 1873 (additional source)
Acrorhynchides Strand, 1928 (additional source)
Acryptolaria Norman, 1875 (additional source)
Acthelmis Lütken, 1875 (additional source)
Actinarctus Schulz, 1935 (additional source)
Actinernus Verrill, 1879 (additional source)
Actinocythereis Puri, 1953 † (additional source)
Actinonema Cobb, 1920 (additional source)
Actinoposthia An der Lan, 1936 (additional source)
Actinopyga Bronn, 1860 (additional source)
Actinoscyphia Stephenson, 1920 (additional source)
Actinostola Verrill, 1883 (additional source)
Actitis lliiger, 1811 (additional source)
Aculeorhynchus Schilke, 1969 (additional source)
Adagnesia Kott, 1963 (additional source)
Adeloposthia An der Lan, 1936 accepted as Paraproporus Westblad, 1945 (additional source)
Adelosina d'Orbigny, 1826 (additional source)
Adenocauda Dörjes, 1968 (additional source)
Adenopharynx Ehlers, 1972 (additional source)
Adercodon Mackie, 1994 (additional source)
Adercotryma Loeblich & Tappan, 1952 (additional source)
Adoncholaimus Filipjev, 1918 (additional source)
Aedicira Hartman, 1957 represented as Aricidea (Aedicira) Hartman, 1957 (additional source)
Aegaeon Agassiz, 1846 (additional source)
Aegialoalaimus de Man, 1907 (additional source)
Aeginina Norman, 1905 (additional source)
Aeginopsis Brandt, 1835 (additional source)
Aeginura Haeckel, 1879 (additional source)
Aeolis Menke, 1844 accepted as Aeolidia Cuvier, 1798 (additional source)
Aepopsis Jeannel, 1922 (additional source)
Aepus Leach in Samouelle, 1819 (additional source)
Aetheolineus Senz, 1993 (additional source)
Aethozoon Hayward, 1978 (additional source)
Aetomylaeus Garman, 1908 (basis of record)
Affinetrina Łuczkowska, 1972 (additional source)
Afrocardium Tomlin, 1931 (additional source)
Afronta Hyman, 1944 (additional source)
Afropinnotheres Manning, 1993 (additional source)
Agabus Leach, 1817 (additional source)
Agalmopsis Sars, 1846 accepted as Agalma Eschscholtz, 1825 (additional source)
Agamascaris Steiner, 1924 (basis of record)
Agamonema Diesing, 1851 (additional source)
Agnezia Monniot C. & Monniot F., 1991 (additional source)
Ahliesaurus Bertelsen, Krefft & Marshall, 1976 (additional source)
Aidablennius Whitley, 1947 (additional source)
Aiptasiogeton Schmidt, 1972 (additional source)
Akessonia Bresciani & Lützen, 1962 (additional source)
Akrostomum Grube, 1840 accepted as Valdivianemertes Stiasny-Wijnhoff, 1923 (additional source)
Alabaminella Saidova, 1975 (additional source)
Alaemon Keyserling & Blasius, 1840 (additional source)
Alaimella Cobb, 1920 (additional source)

 authority

 for Exechonella Canu & Bassler in Duvergier, 1924

Canu & lecointre, 1924 [details]

 authority

 for Hippomonavella Canu & Bassler in Bassler, 1934

Bassler, 1934 [details]

 authority

 for Hippopleurifera Canu & Bassler, 1925

Canu & Lecointre, 1925 [details]

 authority

 for Jaculina Jullien in Jullien & Calvet, 1903

Jullien & Calvet, 1903 [details]

 authority

 for Ragionula Canu & Bassler, 1927

Canu & Lecointre, 1925 [details]

 Nomenclature

 for Luetkenia Duncan, 1878

This is a homonym of Luetkenia Claus, 1864, a Crustacea genus. Not all species in Luetkenia Duncan have been ... [details]

 Publication date

 for Metalcyonidium d'Hondt, 1976

1976 [details]

 Publication date

 for Pseudalcyonidium d'Hondt, 1976

1976 [details]

 Publication date

 for Tervia Jullien, 1882

1882 [details]

 Publication date

 for Zoobotryon Ehrenberg, 1831

Ehrenberg, 1831 (pls. 1828) [details]