DiatomBase
Between brackets is the number of accepted extant species
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- Bacillariophyceae (5 958)
- Subclass Bacillariophyceae incertae sedis (189)
- Subclass Bacillariophycidae (4 408)
- Subclass Coscinodiscophycidae (878)
- Superorder Biddulphianae (230)
- Superorder Chaetocerotanae (95)
- Superorder Corethranae (1)
- Superorder Coscinodiscanae (300)
- Superorder Cymatosirophycanae (10)
- Superorder Lithodesmiophycanae (7)
- Superorder Rhizosolenianae (38)
- Superorder Thalassiosiranae (192)
- Order Thalassiosirales (192)
- Family Lauderiaceae (Schütt) Lemmermann, 1899, sensu emend. (1)
- Family Skeletonemaceae Lebour, 1930, sensu emend. (2)
- Family Stephanodiscaceae Glezer & Makarova, 1986 (150)
- Family Thalassiosiraceae Lebour, 1930 (39)
- Genus Conticribra K. Stachura-Suchoples & D.M. Williams, 2009 (1)
- Genus Coscinosira H.H. Gran, 1900 (1)
- Genus Lineaperpetua Yu, You, Kociolek & Q.Wang (1)
- Genus Livingstonia A.K.S.K. Prasad in Prasad & Nienow, 2011
- Genus Mediolabrus Yang Li, 2020 (1)
- Genus Microsiphona C.I. Weber, 1970
- Genus Minidiscus G.R. Hasle, 1973 emend Park in Park et al., 2017 (5)
- Genus Parthaea S. Gowthaman, 1996
- Genus Planktoniella F. Schütt, 1892
- Genus Porosira E. Jorgensen, 1905
- Genus Praestephanos A.Tuji & M.Julius, 2014
- Genus Roundia Makarova, 1994
- Genus Shionodiscus A.J. Alverson, S.H. Kang & E.C. Theriot, 2006 (3)
- Genus Sinerima Nesterovich & Caissie, 2018 (1)
- Genus Spicaticribra J. Johansen, J.P. Kociolek & R. Lowe, 2008 (4)
- Genus Stephanocyclus A.P. Skabitschevsky, 1975
- Genus Takanoa I.V. Makarova, 1994
- Genus Thalassiocyclus H. Håkansson & A. Mahood, 1993
- Genus Thalassiosira P.T. Cleve, 1873 emend. Hasle, 1973 (22)
- Species Thalassiosira aculeata Proshkina-Lavrenko, 1956
- Species Thalassiosira adamsi Mertz, 1966
- Species Thalassiosira adeliae Manguin, 1957
- Species Thalassiosira aestivalis Gran, 1931
- Species Thalassiosira affinis Makarova, 1961
- Species Thalassiosira allenii Takano, 1965
- Species Thalassiosira ambigua O.G.Kozlova, 1962
- Species Thalassiosira andamanica A.D.Gedde, 1999
- Species Thalassiosira angstii (Gran) Makarova, 1971 accepted as Coscinodiscus angstii var. angstii Gran in Gran & Angst, 1931
- Species Thalassiosira angulata (W.Gregory) Hasle, 1978 accepted as Orthosira angulata Gregory, 1857
- Species Thalassiosira anguste-lineata (A.Schmidt) G.Fryxell & Hasle, 1977 accepted as Coscinodiscus angustelineatus Schmidt in Schmidt et al., 1878
- Species Thalassiosira annaliae Voltolina, 1971
- Species Thalassiosira antarctica Comber, 1896
- Species Thalassiosira antarctica Karsten, 1905
- Species Thalassiosira antiqua (Grunow) Cleve
- Species Thalassiosira atlantica Goryanova, 1958
- Species Thalassiosira aurivillii Cleve, 1901
- Species Thalassiosira australiensis (Grunow) Hasle in Hasle & Lange, 1989 accepted as Coscinodiscus australiensis Grunow, 1884
- Species Thalassiosira australis M.Peragallo, 1921
- Species Thalassiosira baldaufii Boden, 1993
- Species Thalassiosira baltica (Grunow) Ostenfeld, 1901
- Species Thalassiosira binata Fryxell, 1977
- Species Thalassiosira bingensis Takano, 1980
- Species Thalassiosira bioculata (Grunow) Ostenfeld, 1903
- Species Thalassiosira bipartita (Rattray) Hallegraeff, 1992 accepted as Coscinodiscus bipartitus Rattray, 1890
- Species Thalassiosira bipora M. Shiono, 2000
- Species Thalassiosira blanda (A.Schmidt) T.V.Desikachary & Gowthaman, 1989 accepted as Planktoniella blanda (A.Schmidt) E.E.Syvertsen & G.R.Hasle, 1993
- Species Thalassiosira blandus (A. Schmidt) Desikachary & Gowthaman in Desikachary, 1989 accepted as Coscinodiscus blandus A.Schmidt, 1878
- Species Thalassiosira borealis Koizumi, 1980
- Species Thalassiosira bramaputrae (Ehrenberg) Håkansson & Locker, 1981 accepted as Stephanodiscus bramaputrae Ehrenberg, 1854
- Species Thalassiosira brunii Akiba & Yangisawa, 1985
- Species Thalassiosira bukryi Barron, 1983
- Species Thalassiosira bulbosa Syvertsen in Syvertsen & Hasle, 1984
- Species Thalassiosira bungerensis R.M. Gogorev & Z.V. Pushina in Gogorev et al., 2010
- Species Thalassiosira burckliana Schrader, 1974
- Species Thalassiosira californica Tanimura, 1996
- Species Thalassiosira cardiophora Round, 1988
- Species Thalassiosira caspica Makarova, 1959
- Species Thalassiosira castanea Akiba & Yanagisawa, 1998
- Species Thalassiosira catharinensis M. Garcia in M. Garcia & D. Bärwaldt Dutra, 2016
- Species Thalassiosira cedarkeyensis A.K.S.K.Prasad, 1993
- Species Thalassiosira centra M. Shiono, 2000
- Species Thalassiosira chilensis Krasske, 1941
- Species Thalassiosira clevei Gran, 1897
- Species Thalassiosira complicata Gersonde, 1991
- Species Thalassiosira concava Semina, 1991
- Species Thalassiosira concaviuscula I.V.Makarova, 1978
- Species Thalassiosira condensata Cleve, 1900
- Species Thalassiosira conferta Hasle, 1977
- Species Thalassiosira confusa Makarova, 1975
- Species Thalassiosira congoi Leuduger-Fortmorel, 1898
- Species Thalassiosira constricta Gaarder, 1938 accepted as Bacterosira constricta (Gaarder, 1938) J.S. Park & J.H. Lee, 2016
- Species Thalassiosira convexa V.V.Muchina, 1965
- Species Thalassiosira coramandeliana Subrahmanyan, 1946
- Species Thalassiosira coromandeliana Subrahmanyan, 1946
- Species Thalassiosira coronata Gaarder, 1951
- Species Thalassiosira coronata Proschkina-Lavrenko, 1955
- Species Thalassiosira coronifera Proschkina-Lavrenko, 1961
- Species Thalassiosira cretacea Deflandre, 1941
- Species Thalassiosira cryophila Kisselev, 1931
- Species Thalassiosira cuitzeonensis I.Israde, K.Serieyssol & F.Gasse, 1998 †
- Species Thalassiosira curiosa Hajós, 1973
- Species Thalassiosira curviseriata Takano, 1981
- Species Thalassiosira decipiens (Grunow) E.G.Jørgensen, 1905
- Species Thalassiosira decorata Cleve-Euler, 1941
- Species Thalassiosira decrescens Skabichevskaya, 1984
- Species Thalassiosira delicata (Barron) Akiba, 1985 accepted as Thalassiosira nidulus var. delicata Barron, 1980
- Species Thalassiosira delicatissima Proschkina-Lavrenko, 1960
- Species Thalassiosira delicatula Hustedt, 1958
- Species Thalassiosira delicatula Ostenfeld, 1908
- Species Thalassiosira densannula Hasle & Fryxell, 1977
- Species Thalassiosira depressa M. Shiono, 2000 †
- Species Thalassiosira dichotomica (O.G.Kozlova) G.A.Fryxell & G.R.Hasle, 1983 accepted as Porosira dichotomica O.G.Kozlova, 1962
- Species Thalassiosira diporocyclus Hasle, 1972
- Species Thalassiosira dispar (M.Peragallo & J.Héribaud) K.Serieyssol, 1998 † accepted as Coscinodiscus dispar var. dispar M. Peragallo & Héribaud in Héribaud, 1893
- Species Thalassiosira distans Pouchet, 1891
- Species Thalassiosira dolmatovae Oreshkina ex A.Gladenkov, 2013 †
- Species Thalassiosira dubia Kozlova, 1962
- Species Thalassiosira dubia Leuduger-Fortmorel, 1892
- Species Thalassiosira dubiosa Schrader in Schrader & Fenner, 1976
- Species Thalassiosira duostra C.Pienaar, 1990
- Species Thalassiosira eccentrica (Ehrenberg) Cleve, 1904
- Species Thalassiosira echinata Semina in Semina & Fryxell, 1994
- Species Thalassiosira elegans (Brun in Brun & Tempère) Jousé, 1961 accepted as Stephanodiscus elegans Brun in Brun & Tempère, 1889
- Species Thalassiosira elliptipora J.Fenner ex A.D.Mahood & J.A.Barron
- Species Thalassiosira elliptipora (Donahue) Fenner, 1991
- Species Thalassiosira elsayedii Fryxell, 1975
- Species Thalassiosira endoseriata Hasle & G.Fryxell, 1977
- Species Thalassiosira excentrica Karsten, 1905
- Species Thalassiosira exceptiuncula Shiono
- Species Thalassiosira exigua G.Fryxell & Hasle, 1977
- Species Thalassiosira expecta VanLandingham, 1978
- Species Thalassiosira fallax Meunier, 1910
- Species Thalassiosira fallax Kozlova, 1962
- Species Thalassiosira fasciculata Harwood & Maruyama, 1992
- Species Thalassiosira faurii (Gasse) Hasle, 1978 accepted as Coscinodiscus faurii Gasse, 1975
- Species Thalassiosira favosa Makarova in Makarova & Sukhanova, 1998
- Species Thalassiosira feibelii Brindle & Mohan in Brindle et al., 2018 †
- Species Thalassiosira ferelineata Hasle & G.A.Fryxell, 1977
- Species Thalassiosira flexosa (Brun) Akiba & Yanagisawa, 1985 accepted as Coscinodiscus flexuosus var. flexuosus Brun, 1895
- Species Thalassiosira flexuosa (J.Brun) F.Akiba & Y.Yanagisawa
- Species Thalassiosira floridana (I.C.G.Cooper) Hasle, 1972 accepted as Coscinosira floridana I.C.G.Cooper, 1958
- Species Thalassiosira fluviatilis Hustedt, 1926 accepted as Thalassiosira weissflogii (Grunow) G.Fryxell & Hasle, 1977
- Species Thalassiosira fraga Schrader in Schrader & Fenner, 1976
- Species Thalassiosira fragilis G. Fryxell in Fryxell, Gould & Watkins, 1984
- Species Thalassiosira frenguelli Kozlova, 1964
- Species Thalassiosira frenguellii O.G.Kozlova, 1964
- Species Thalassiosira frenguelliopsis G.A.Fryxell & J.R.Johans, 1985
- Species Thalassiosira frigida Cleve-Euler, 1917
- Species Thalassiosira frigida Cleve-Euler, 1942
- Species Thalassiosira fryxelliae Sunesen & Sar, 2004
- Species Thalassiosira gasseae Brindle & Mohan in Brindle et al., 2018 †
- Species Thalassiosira gelatinosa Hensen, 1887
- Species Thalassiosira gelatinosus Lemmermann, 1899
- Species Thalassiosira gerloffii Rivera, 1981
- Species Thalassiosira gersondei Barron in Baldauf & Barron, 1991
- Species Thalassiosira gessneri Hustedt, 1956
- Species Thalassiosira gracilis (Karsten) Hustedt, 1958 accepted as Coscinodiscus gracilis Karsten, 1905
- Species Thalassiosira gravida Cleve, 1896
- Species Thalassiosira grunowii Akiba & Yanagisawa, 1985
- Species Thalassiosira guillardii Hasle, 1978
- Species Thalassiosira hasleae Cassie & Dempsey, 1980
- Species Thalassiosira haynaldiella Jousé, 1961
- Species Thalassiosira hendeyi Hasle & G.Fryxell, 1977
- Species Thalassiosira heteromera Makarova, 1975
- Species Thalassiosira hibernalis Gayoso, 1989
- Species Thalassiosira hispanica Paulsen, 1930 (1931)
- Species Thalassiosira hispida Syvertsen, 1986
- Species Thalassiosira hustedtii Poretzky & Anissimova, 1933 accepted as Thalassiosira hendeyi Hasle & G.Fryxell, 1977
- Species Thalassiosira hyalina (Grunow) Gran, 1897
- Species Thalassiosira hyalinopsis Barron, 1975
- Species Thalassiosira hydra Gombos in Gombos & Ciesielski, 1983
- Species Thalassiosira hyperborea (Grunow) Hasle in Hasle & Lange, 1989
- Species Thalassiosira ignota Makarova, 1975
- Species Thalassiosira incerta Makarova, 1961
- Species Thalassiosira indefinita Jousé, 1959
- Species Thalassiosira indica Kazarina, 1978
- Species Thalassiosira inlandica Hayashi, 2007 † accepted as Spicaticribra inlandica (Hayashi) Adesalu & Julius
- Species Thalassiosira insigna (Jousé) Harwood & Maruyama, 1992 accepted as Actinocyclus complanatus var. complanatus Castracane, 1886
- Species Thalassiosira intermedia Makarova, 1988
- Species Thalassiosira intrannula Herzig & Fryxell, 1986
- Species Thalassiosira inura Gersonde, 1991
- Species Thalassiosira irregulata Schrader in Schrader & Fenner, 1976
- Species Thalassiosira jacksonii Koizumi & Barron in Koizumi, 1980
- Species Thalassiosira japonica Kisselev, 1935
- Species Thalassiosira jouseae Akiba, 1985
- Species Thalassiosira kanayae Tanimura, 1996
- Species Thalassiosira karenae Semina, 1981
- Species Thalassiosira khursevicha Laslandes & Kociolek in Kociolek et al., 2014
- Species Thalassiosira kilarskii I.Kaczmarska, 1985 † accepted as Spicaticribra kilarskii (Kaczmarska) Kociolek & Khursevich in Khursevich & Kociolek, 2012 †
- Species Thalassiosira kolbei (Jousé) Gersonde, 1990 accepted as Coscinodiscus kolbei A.P.Jousé, 1965
- Species Thalassiosira kozlovii Makarova, 1971
- Species Thalassiosira kryophila (Grunow) E.Jørgensen, 1905 accepted as Coscinodiscus kryophilus Grunow, 1884
- Species Thalassiosira kushirensis Takano, 1985
- Species Thalassiosira labimarginata Bodén, 1993
- Species Thalassiosira lacustris (Grunow) Hasle, 1977 represented as Lineaperpetua lacustris (Grunow) Yu, You, Kociolek & Wang, 2024
- Variety Thalassiosira lacustris var. cassiospinua Cai & Xie in Xie & Cai, 1981
- Variety Thalassiosira lacustris var. hyperborea (Grunow) Qi in Qi, Zhang & Lin, 1980
- Variety Thalassiosira lacustris var. nipponica (Skvortzow) Qi in Qi, Zhang & Lin, 1980
- Variety Thalassiosira lacustris var. proximus (Makarova) Makarova, 1983 accepted as Coscinodiscus proximus Makarova, 1961
- Variety Thalassiosira lacustris var. septentrionalis (Grunow) Qi in Qi, Zhang & Lin, 1980
- Variety Thalassiosira lacustris var. septentrionalis (Grunow) Makarova, 1983
- Variety Thalassiosira lacustris var. sinica (Skvortzow) Qi in Qi, Zhang & Lin, 1980 accepted as Coscinodiscus sinicus Skvortzow, 1946
- Species Thalassiosira laevis Gao & Cheng, 1992
- Species Thalassiosira latimarginata Makarova, 1975
- Species Thalassiosira lentiginosa (Janisch) Fryxell, 1977 accepted as Coscinodiscus lentiginosus var. lentiginosus Janisch in Schmidt et al., 1878
- Species Thalassiosira leptopus (Grunow ex Van Heurck) Hasle & G.Fryxell, 1977
- Species Thalassiosira levanderi van Goor, 1924
- Species Thalassiosira licea G.Fryxell, 1978
- Species Thalassiosira lindstroemii Boden, 1992
- Species Thalassiosira lineata Jousé, 1968
- Species Thalassiosira lineoides Herzig & Fryxell, 1986
- Species Thalassiosira livingstoniorum A.K.S.K.Prasad, P.Hargraves & J.A.Nienow, 2011
- Species Thalassiosira longifultoportulata R.M.Gogorev & Z.V.Pushina, 2010 †
- Species Thalassiosira longissima Cleve, 1906-1908
- Species Thalassiosira lundiana Fryxell, 1975
- Species Thalassiosira lusca Schrader in Schrader & Fenner, 1976
- Species Thalassiosira maculata G.A.Fryxell & J.R.Johansen, 1985
- Species Thalassiosira maeotica Proschkina-Lavrenko, 1960
- Species Thalassiosira mahoodii Barron in Baldauf & Barron, 1991
- Species Thalassiosira makarovae Mukhina, 1978
- Species Thalassiosira mala Takano, 1965
- Species Thalassiosira manifesta Sheshukova-Poretzkaja, 1964
- Species Thalassiosira manifesta Sheshukova-Poretskaya, 1961
- Species Thalassiosira manifesta Sheshukova-Poretzky emend Makarova in Gleser, Makarova, Moiseeva & Nikolaev, 1988
- Species Thalassiosira margaritae (Frenguelli & Orlando) O.G.Kozlova, 1962 accepted as Coscinodiscus margaritae Frenguelli & Orlando, 1958
- Species Thalassiosira marginata Venkataraman, 1939
- Species Thalassiosira marujamica Sheshukova-Poretzkaya, 1959
- Species Thalassiosira marujamica Sheshukova-Poretzky emend Makarova in Gleser, Makarova, Moiseeva & Nikolaev, 1988
- Species Thalassiosira mediaconvexa Schrader in Schrader & Fenner, 1976
- Species Thalassiosira mediterranea (Schröder) Hasle, 1972 accepted as Coscinosira mediterranea Schröder, 1911
- Species Thalassiosira mendiolana Hasle & Heimdal, 1970
- Species Thalassiosira minicosmica Lee & Park, 2015
- Species Thalassiosira minima Gaarder, 1951
- Species Thalassiosira minima Mertz, 1966
- Species Thalassiosira minuscula Krasske, 1941
- Species Thalassiosira minutissima Oreshkina in Barron & Gladenkov, 1995
- Species Thalassiosira miocenica Schrader, 1974
- Species Thalassiosira mioplicata Akiba & Yanagisawa, 1985
- Species Thalassiosira mirniae Jousé, 1962
- Species Thalassiosira mirnyi Jousé, 1965
- Species Thalassiosira mizunamiensis Yanagisawa, 1993
- Species Thalassiosira moholensis (Schrader) Akiba & Yanagisawa, 1985 accepted as Coscinodiscus moholensis Schrader, 1974
- Species Thalassiosira monile Cleve, 1900 (1901)
- Species Thalassiosira monoporocyclus Hasle, 1972
- Species Thalassiosira multipora Whiting & Schrader, 1985
- Species Thalassiosira nana Lohmann, 1908
- Species Thalassiosira nanolineata (A.Mann) Fryxell & Hasle, 1977 accepted as Coscinodiscus nanolineatus Mann, 1925
- Species Thalassiosira nansenii Scherer & Koc, 1996
- Species Thalassiosira nativa Sheshukova-Poretskaya, 1964
- Species Thalassiosira nevadica Khursevich & Van Landingham, 1993
- Species Thalassiosira nidulus (Tempère & Brun in Brun & Tempère) Jousé, 1961 accepted as Stephanopyxis nidulus Tempère & Brun in Brun & Tempère, 1889
- Species Thalassiosira nitzschioides (Grunow) Mereschkowsky, 1902
- Species Thalassiosira nitzschioides Derjugin K.M., 1915
- Species Thalassiosira nodulolineata (Hendey) Hasle & Fryxell, 1977 accepted as Coscinodiscus nodulolineatus Hendey, 1958
- Species Thalassiosira nordenskioeldii Cleve, 1873
- Species Thalassiosira nordenskioldii Cleve emend Berg, 1952
- Species Thalassiosira obica Kozlova, 1967
- Species Thalassiosira oceanica Hasle, 1983
- Species Thalassiosira oestrupii (Ostenfeld) Hasle, 1972 represented as Shionodiscus oestrupii (Ostenfeld) A.J.Alverson, S.H.Kang & E.C.Theriot, 2006
- Species Thalassiosira oliverana
- Species Thalassiosira oliveriana (O'Meara) I.V.Makarova & V.A.Nikolajev, 1983
- Species Thalassiosira opposita Koizumi, 1980
- Species Thalassiosira oranica Hasle, 1985
- Species Thalassiosira ordinaria Makar, 1977
- Species Thalassiosira orientalis Sheshukova-Porezkaya, 1959
- Species Thalassiosira orientalis Sheshukova-Poretzky emend Makarova in Gleser, Makarova, Moiseeva & Nikolaev, 1988
- Species Thalassiosira ornata Proshkina-Lavrenko, 1959
- Species Thalassiosira ostenfeldii Cleve-Euler, 1951
- Species Thalassiosira pacifica Gran & Angst, 1931
- Species Thalassiosira partheneia Schrader, 1972
- Species Thalassiosira parva Proschkina-Lavrenko, 1955
- Species Thalassiosira parvula Makarova, 1977
- Species Thalassiosira patagonica N. Maidana, 1999 accepted as Spicaticribra patagonica (Maidana) Kociolek & Khursevich in Khursevich & Kociolek, 2012
- Species Thalassiosira perispinosa Tanimura, 1996
- Species Thalassiosira perpusilla Kozlova, 1967
- Species Thalassiosira planiuscula (Rattray) D.M. Harwood & T. Maruyama, 1992 accepted as Coscinodiscus planiusculus Rattray, 1890
- Species Thalassiosira plicata Schrader, 1974
- Species Thalassiosira plicatoides (Simonsen) Akiba & Yanagisawa, 1985 accepted as Coscinodiscus plicatoides Simonsen, 1974
- Species Thalassiosira polychorda (Gran) E.Jorgensen, 1899 accepted as Coscinodiscus polychordus Gran, 1897
- Species Thalassiosira poro-irregulata Hasle & Heimdal, 1970
- Species Thalassiosira poroseriata (Ramsfjell) Hasle, 1972 accepted as Coscinosira poroseriata Ramsfjell, 1959
- Species Thalassiosira porosiroides Makarova, 1991
- Species Thalassiosira praeconvexa Burckle, 1972
- Species Thalassiosira praeconvexa Burckle emend Gersonde & Schrader, 1984
- Species Thalassiosira praefraga Gladenkov & Barron, 1995 †
- Species Thalassiosira praekryophila Oreshkina in Oreshkina & Vitukhin, 1987
- Species Thalassiosira praenidulus Akiba, 1985
- Species Thalassiosira praeoestrupii M.P.Dumont, J.G.Baldauf & J.A.Barron, 1986 †
- Species Thalassiosira praeyabei (Schrader) Akiba & Yanagisawa, 1985 accepted as Coscinodiscus praeyabei Schrader, 1973
- Species Thalassiosira primalabiata Gombos in Gombos & Ciesielski, 1983
- Species Thalassiosira profunda (Hendey) Hasle, 1973
- Species Thalassiosira proschkinae Makarova, 1979
- Species Thalassiosira pseudomultipora Makarova, 1990
- Species Thalassiosira pseudonana Hasle & Heimdal, 1970
- Species Thalassiosira pulchella Takano, 1963
- Species Thalassiosira punctata Jousé, 1959
- Species Thalassiosira punctata Jousé, 1961
- Species Thalassiosira punctatus Venkataraman, 1941
- Species Thalassiosira punctifera (Grunow) Fryxell, Simonsen & Hasle, 1974 accepted as Coscinodiscus excentricus var. punctifera Grunow, 1884
- Species Thalassiosira punctigera (Castracane) Hasle, 1983 accepted as Ethmodiscus punctiger Castracane, 1886
- Species Thalassiosira regulata Kazarina, 1978
- Species Thalassiosira ritscheri (Hustedt) Hasle, 1970 accepted as Coscinodiscus ritscheri Hustedt, 1958
- Species Thalassiosira rosulata Takano, 1985
- Species Thalassiosira rotula Meunier, 1910 accepted as Thalassiosira gravida Cleve, 1896
- Species Thalassiosira rudis P.Tremarin, T.Ludwig, V.Becker & L.Torgan, 2008 accepted as Spicaticribra rudis (P.Tremarin, T.Ludwig, V.Becker & L.Torgan) A.Tuji, P.Leelahakriengkrai & Y. Peerapornpisal, 2012
- Species Thalassiosira rudolfii (Bachmann) Hasle, 1978 accepted as Coscinodiscus rudolfi Bachmann, 1938
- Species Thalassiosira sackettii G. Fryxell, 1977
- Species Thalassiosira salvadoriana Hustedt, 1956
- Species Thalassiosira sancettae Akiba, 1985
- Species Thalassiosira sarmatica Hajós, 1973
- Species Thalassiosira saturni Lohmann, 1908
- Species Thalassiosira scotia Fryxell & Hoban, 1979
- Species Thalassiosira sheshukovae Makarova, 1988
- Species Thalassiosira simonsenii Hasle & G.Fryxell, 1977
- Species Thalassiosira simplex Hustedt, 1956
- Species Thalassiosira singularis Sheshukova-Poretskaya, 1967
- Species Thalassiosira solitaria Gayoso, 1985
- Species Thalassiosira spicula Kozlova, 1967
- Species Thalassiosira spinoconvexa Akiba & Yanagisawa, 1998
- Species Thalassiosira spinosa H.J.Schrader, 1976
- Species Thalassiosira spinosa Simonsen, 1974
- Species Thalassiosira spinulata Takano, 1981
- Species Thalassiosira spumellaroides Schrader, 1976
- Species Thalassiosira stellaris Hasle & Guillard, 1977
- Species Thalassiosira strelnikoviae Makarova, 1976
- Species Thalassiosira striata Harwood & Maruyama, 1992
- Species Thalassiosira subsalina Proshkina-Lavrenko, 1955
- Species Thalassiosira subtilis (Ostenfeld) Gran, 1900
- Species Thalassiosira sundarbana B. Samanta & P. Bhadury, 2015
- Species Thalassiosira symbolophora Schrader, 1974
- Species Thalassiosira symmetrica G.A.Fryxell & Hasle, 1973
- Species Thalassiosira tappanae Barron, 1985
- Species Thalassiosira tcherniai Manguin, 1957
- Species Thalassiosira tealata Takano, 1980
- Species Thalassiosira temperei (Brun) Akiba & Yanagisawa, 1985 accepted as Coscinodiscus temperei Brun in Brun & Tempère, 1889
- Species Thalassiosira tenera Proschkina-Lavrenko, 1961
- Species Thalassiosira tertiaria Sheshukova-Poretskaya, 1967
- Species Thalassiosira tetraoestrupii Bodén, 1993 †
- Species Thalassiosira thailandica Boonyapiwat in Boonyapiwat & Takano, 1986
- Species Thalassiosira torokina Brady, 1977
- Species Thalassiosira transitoria Tanimura, 1996
- Species Thalassiosira trifulta G.Fryxell, 1979
- Species Thalassiosira tropica Misra, 1956
- Species Thalassiosira tubifera Fryxell, 1975
- Species Thalassiosira tumida (Janisch) Hasle, 1971 accepted as Coscinodiscus tumidus var. tumidus Janisch in Schmidt et al., 1878
- Species Thalassiosira ulna Kozlova, 1967
- Species Thalassiosira umaoiensis Akiba, 1985
- Species Thalassiosira undulosa (Mann) Sheshukova-Poretskaya, 1967 accepted as Coscinodiscus undulosus var. undulosus Mann, 1907
- Species Thalassiosira urahoroensis Akiba, 1985
- Species Thalassiosira usachevii Jousé, 1959
- Species Thalassiosira usatschevii Jousé, 1961
- Species Thalassiosira variabilis
- Species Thalassiosira variantia M.Shiono, 2001 †
- Species Thalassiosira visurgis Hustedt, 1957
- Species Thalassiosira voeringensis Bodén, 1992
- Species Thalassiosira vulnifica (Gombos) Fenner amend Mahood & Barron, 1996 accepted as Coscinodiscus vulnificus Gombos, 1976
- Species Thalassiosira webbi Harwood & Maruyama, 1992
- Species Thalassiosira weissflogii (Grunow) G.Fryxell & Hasle, 1977 accepted as Micropodiscus weissflogii Grunow, 1885
- Species Thalassiosira willei Henckel, 1925
- Species Thalassiosira wongii Mahood in Mahood, Fryxell & McMillan, 1986
- Species Thalassiosira yabei (Kanaya) Akiba & Yanagisawa, 1985 accepted as Coscinodiscus yabei Kanaya, 1959
- Species Thalassiosira zabelinae Jousé, 1959 accepted as Eupyxidicula zabelinae (Jousé) S.Blanco & C.E.Wetzel, 2016
- Family Thalassiosiropsidaceae
- Family Trochosiraceae
- Order Arcanodiscales (5)
- Order Stictocyclales
- Subclass Fragilariophycidae (483)
- Order Centrales
