Acanthocorbis tintinnabulum Marchant, van den Hoff & Burton, 1987 (basis of record)
Acanthocorbis unguiculata (Thomsen) Hara & Takahashi, 1984 (additional source)
Acanthocystis (basis of record)
Acanthocystis paliformis Durrschmidt, 1987 (basis of record)
Acanthocystis perpusilla Petersen & Hansen, 1960 (basis of record)
Acanthocystis turfacea Carter, 1863 (basis of record)
Acanthoeca brevipoda W.Ellis, 1930 (additional source)
Acanthoeca spectabilis W.N.Ellis, 1930 (additional source)
Acanthoecopsis asymmetrica Thomsen (additional source)
Acanthostomella norvegica (Daday, 1887) (basis of record)
Achnanthes brevipes C.Agardh, 1824 (additional source)
Achnanthes vicentii Manguin, 1957 (basis of record)
Acineta grahami Allgin, 1955 (basis of record)
Acropisthiidae Foissner & Foissner, 1988 (basis of record)
Actimonas (basis of record)
Actimonas mirabilis Kent, 1880 (basis of record)
Actinocyclus actinochilus (Ehrenberg) Simonsen, 1982 accepted as Coscinodiscus actinochilus Ehrenberg, 1844 (basis of record)
Actinocyclus adeliae Manguin, 1957 (basis of record)
Actinocyclus curvulatus (basis of record)
Actinocyclus divisus (Grunow) Hustedt, 1958 accepted as Coscinodiscus divisus var. divisus Grunow, 1878 (basis of record)
Actinocyclus exiguus G.Fryxell & Semina, 1981 (basis of record)
Actinocyclus octonarius Ehrenberg, 1837 accepted as Actinoptychus octonarius (Ehrenberg) Kützing, 1844 accepted as Actinocyclus octonarius var. octonarius Ehrenberg, 1837 (additional source)
Actinocyclus spiritus T.P.Watkins, 1986 (basis of record)
Actinoptychus senarius (Ehrenberg) Ehrenberg, 1843 accepted as Actinocyclus senarius Ehrenberg, 1838 (additional source)
Aegyriana Song & Wilbert, 2002 (basis of record)
Aegyriana paroliva Song & Wilbert, 2002 accepted as Aegyria paroliva (Song & Wilbert, 2002) Chen et al., 2012 (basis of record)
Alexandrium tamarense (Lebour) Balech, 1995 (additional source)
Amphidinium hadae Balech, 1976 (additional source)
Amphiprora kufferathii Manguin, 1960 (basis of record)
Amphora racovitzae van Heurck, 1909 (basis of record)
Amphorellopsis quinquealata (Laackmann) Balech, 1971 (basis of record)
Amphorides laackmanni (Jörgensen) Strand, 1928 (basis of record)
Anisonema prosgeobium Skuja, 1939 (additional source)
Ascohnissimplex (basis of record)
Aspidisca antarctica Corliss & Snyder, 1986 (basis of record)
Aspidisca crenata Fabre-Domergue, 1885 (basis of record)
Aspidisca polypoda (Dujardin, 1841) (basis of record)
Aspidisca quadrilineata Kahl, 1932 accepted as Aspidisca aculeata (Ehrenberg, 1838) Kahl, 1932 (basis of record)
Aspidisca terranovae Valbonesi, 1996 (basis of record)
Asteromphalus C.G. Ehrenberg, 1844 (additional source)
Asteromphalus heptactis (Brébisson) Ralfs, 1861 (additional source)
Asteromphalus hookeri Ehrenberg, 1844 (additional source)
Asteromphalus hyalinus Karsten, 1905 (basis of record)
Asteromphalus parvulus Karsten, 1905 (basis of record)
Asteromphalus roperianus (Greville) Ralfs, 1861 (basis of record)
Auricula compacta (Hustedt) L.K.Medlin, 1990 accepted as Nitzschia compacta Hustedt, 1958 (basis of record)
Azpeitia nodulifera (A.W.F.Schmidt) G.A.Fryxell & P.A.Sims, 1986 (additional source)
Azpeitia tabularis (Grunow) G.Fryxell & P.A.Sims, 1986 accepted as Coscinodiscus tabularis var. tabularis Grunow, 1884 (basis of record)
Banquisia T.B.B. Paddock, 1988 (basis of record)
Banquisia belgicae (Van Heurck) Paddock, 1988 accepted as Amphiprora belgicae var. belgicae Van Heurck, 1909 (basis of record)
Berkeleya rutilans (Trentepohl ex Roth) Grunow, 1880 (additional source)
Bicosta antennigera Moestrup, 1979 (additional source)
Bicosta spinifera (Throndsen) Leadbeater, 1978 (additional source)
Blepharocysta splendor-maris (Ehrenberg) F.Stein, 1883 (additional source)
Bodo curvifilus Griessmann, 1913 (additional source)
Bursaopsis Kofoid & Campbell, 1929 (basis of record)
Bursaopsis conicoides Hada, 1970 (basis of record)
Bursaopsis ollula Hada, 1970 (basis of record)
Cafeteria roenbergensis Fenchel & D.J.Patterson, 1988 (additional source)
Calcidiscaceae J.R.Young & Bown, 1997 (basis of record)
Calcidiscus leptoporus (G.Murray & V.H.Blackman) Loeblich & Tappan, 1978 † (additional source)
Calliacantha natans (Grøntved) Leadbeater, 1978 (additional source)
Calliacantha simplex Manton & Oates, 1979 (additional source)
Caneosphaera molischii (Schiller) Gaarder, 1977 accepted as Syracosphaera molischii J.Schiller, 1925 (additional source)
Centrohelida (basis of record)
Ceratium extensum (Gourret) Cleve-Euler, 1900 accepted as Tripos extensus (Gourret) F.Gómez, 2013 (additional source)
Ceratium fusus (Ehrenberg) Dujardin, 1841 accepted as Tripos fusus (Ehrenberg) F.Gómez, 2013 (additional source)
Ceratium lineatum (Ehrenberg) Cleve, 1899 accepted as Tripos lineatus (Ehrenberg) F.Gómez, 2013 (additional source)
Ceratium pentagonum Gourret, 1883 accepted as Tripos pentagonus (Gourret) F.Gómez, 2013 (additional source)
Ceratium tripos (O.F.Müller) Nitzsch, 1817 accepted as Tripos muelleri Bory de Saint-Vincent, 1826 (additional source)
Chaenea Quennerstedt, 1867 (basis of record)
Chaenea teres (Dujardin, 1841) Kent, 1881 (basis of record)
Chaetoceros adelianum E. Manguin, 1957 (basis of record)
Chaetoceros aequatorialis Cleve, 1873 (basis of record)
Chaetoceros aequatorialis var. antarctica (basis of record)
Chaetoceros atlanticus Cleve, 1873 (additional source)
Chaetoceros brevis F.Schütt, 1895 (additional source)
Chaetoceros bulbosus (Ehrenberg) Heiden, 1928 (basis of record)
Chaetoceros castracanei Karsten, 1905 (basis of record)
Chaetoceros concavicornis Mangin, 1917 (additional source)
Chaetoceros convolutus Castracane, 1886 (additional source)
Chaetoceros criophilus Gran, 1904 (additional source)
Chaetoceros curvatus Castracane, 1886 (basis of record)
Chaetoceros curvisetus Cleve, 1889 (additional source)
Chaetoceros debilis Cleve, 1894 emend Xu, Y.Li & Lundholm in Xu et al., 2020 (additional source)
Chaetoceros dichaeta Ehrenberg, 1844 (additional source)
Chaetoceros flexuosus Mangin, 1915 (basis of record)
Chaetoceros gaussii Heiden, 1928 (basis of record)
Chaetoceros hendeyi Manguin, 1960 (basis of record)
Chaetoceros laciniosus F.Schütt, 1895 (additional source)
Chaetoceros neglectus Karsten, 1905 (basis of record)
Chaetoceros neogracilis VanLand., 1968 (additional source)
Chaetoceros pendulus Karsten, 1905 (additional source)
Chaetoceros peruvianum Brightwell, 1856 (additional source)
Chaetoceros radicans F.Schütt, 1895 (additional source)
Chaetoceros simplex Ostenfeld, 1902 (additional source)
Chaetoceros socialis H.S.Lauder, 1864 (additional source)
Chaetoceros tortissimus Gran, 1900 (additional source)
Chlamydodontida (basis of record)
Chlamydonella Petz, Song & Wilbert, 1995 (basis of record)