DiatomBase
Between brackets is the number of accepted extant species
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- Bacillariophyceae (5 957)
- Subclass Bacillariophyceae incertae sedis (189)
- Subclass Bacillariophycidae (4 408)
- Superorder Bacillariophycanae (4 083)
- Order Achnanthales (438)
- Order Bacillariales (357)
- Order Cymbellales (792)
- Order Dictyoneidales
- Order Lyrellales (15)
- Order Mastogloiales (88)
- Order Naviculales (2 077)
- Suborder Diploneidineae
- Suborder Naviculineae (12)
- Suborder Neidiineae (330)
- Suborder Phaeodactylineae
- Suborder Sellaphorineae
- Family Amphipleuraceae Grunow, 1862 (162)
- Family Diploneidaceae D. G. Mann, 1990 (116)
- Family Metascolioneidaceae S.Blanco & C.E.Wetzel, 2016 (2)
- Family Naviculaceae Kützing, 1844 (866)
- Family Naviculales incertae sedis (7)
- Family Pinnulariaceae D.G. Mann, 1990 (254)
- Family Pleurosigmataceae Mereschkowsky, 1903 (98)
- Genus Achnanthosigma L. Reinhard, 1882 accepted as Rhoicosigma A. Grunow, 1867
- Genus Arcuatasigma G.Reid, 2012 (7)
- Genus Carinasigma G.Reid, 2012 (3)
- Genus Cochlearisigma G.Reid, 2012 (5)
- Genus Costasigma G.Reid, 2012 (2)
- Genus Donkinia J. Ralfs in A. Pritchard, 1861 (1)
- Genus Gyrosigma A.H. Hassall, 1845 (33)
- Genus Hyalosigma N.I. Strelnikova & J.P. Kociolek in Strelnikova, Kociolek & Fourtanier, 2006 †
- Genus Pleurosigma W. Smith, 1852 (38)
- Species Pleurosigma abruptum H. Peragallo, 1891
- Species Pleurosigma acuminatum (Kützing) W.Smith, 1852 accepted as Gyrosigma acuminatum (Kützing) Rabenhorst, 1853
- Species Pleurosigma acuminatum (Kützing) Grunow, 1860 accepted as Frustulia acuminata Kützing, 1833
- Species Pleurosigma acuminatum sensu W. Smith, 1853
- Species Pleurosigma acus A.Mann, 1925
- Species Pleurosigma acutum Norman ex Ralfs, 1861
- Species Pleurosigma aequatoiale Cleve in Cleve & Moller, 1878
- Species Pleurosigma aestuarii (Brébisson ex Kützing) W.Smith, 1853
- Species Pleurosigma affine Grunow, 1880
- Species Pleurosigma agellus Ralfs
- Species Pleurosigma akbecula Derjugin, 1928
- Species Pleurosigma allenuatum accepted as Pleurosigma attenuatum (Kützing) W.Smith, 1852
- Species Pleurosigma amara S.R.Stidolph, 1992
- Species Pleurosigma americanum (H. Peragallo) Boyer, 1927 accepted as Pleurosigma decorum var. americanum H. Peragallo, 1891
- Species Pleurosigma angulare Cleve
- Species Pleurosigma angulatum (Queckett) W.Smith, 1852
- Species Pleurosigma angusticonvexum Hagelstein, 1939
- Species Pleurosigma angustum Donkin, 1858
- Species Pleurosigma antarcticum Grunow in Cleve & Möller, 1878
- Species Pleurosigma antillarum H. Peragallo, 1891
- Species Pleurosigma apulum (Rabenhorst) Ralfs in Pritchard, 1861 accepted as Gyrosigma apula Rabenhorst, 1853
- Species Pleurosigma arafurense Castracane, 1886
- Species Pleurosigma arcticum (Cleve) A.Mann, 1937
- Species Pleurosigma arcuatum Donkin, 1857
- Species Pleurosigma asiaticum (Tempère & Brun) H.Peragallo, 1891 accepted as Staurosigma asiaticum Tempère & Brun, 1889 †
- Species Pleurosigma atlanticum Frenguelli, 1928
- Species Pleurosigma atlanticum Heiden & Kolbe, 1928
- Species Pleurosigma attenuatum (Kützing) W.Smith, 1852 accepted as Gyrosigma attenuatum (Kützing) Rabenhorst, 1853
- Species Pleurosigma australe Grunow, 1868
- Species Pleurosigma australicum Witt, 1873
- Species Pleurosigma baileyi Grunow in Cleve & Grunow, 1880
- Species Pleurosigma balearicum Cleve & Grunow in Cleve & Moller, 1878
- Species Pleurosigma balearicum Cleve & Grunow in Rodrígues y Femenías, 1889
- Species Pleurosigma balticosinense Schwarz, 1874
- Species Pleurosigma balticum (Ehrenberg) W.Smith, 1852 accepted as Gyrosigma balticum (Ehrenberg) Rabenhorst, 1853
- Species Pleurosigma barbadense Grunow, 1880 accepted as Pleurosigma marinum var. barbadense Grunow in Cleve & Möller, 1878
- Species Pleurosigma bennettii M. Peragallo in Tempère & Peragallo, 1909
- Species Pleurosigma biharense Pantocsek, 1892
- Species Pleurosigma bistriatum Schumann, 1867
- Species Pleurosigma boyeri Keeley, 1925
- Species Pleurosigma brasiliana Müller-Melchers, 1957
- Species Pleurosigma brasiliense Zimmermann, 1918
- Species Pleurosigma brebissonii Grunow, 1880 accepted as Gyrosigma acuminatum var. brebissonii (Grunow) Cleve, 1894
- Species Pleurosigma brunii Cleve ex H. Peragallo, 1891
- Species Pleurosigma candidum Schumann, 1867
- Species Pleurosigma capense Petit, 1876
- Species Pleurosigma capense Karsten, 1905
- Species Pleurosigma carinatum Donkin, 1858
- Species Pleurosigma chandolense H.P.Gandhi ex Karthick, 2020
- Species Pleurosigma chandolensis H.P. Gandhi, 1998 accepted as Pleurosigma chandolense H.P.Gandhi ex Karthick, 2020
- Species Pleurosigma chilensis Hustedt & Krasske in Krasske, 1941
- Species Pleurosigma clevei Grunow, 1880
- Species Pleurosigma compactum Greville, 1857 accepted as Rhoicosigma compactum (Greville) Grunow, 1877
- Species Pleurosigma constrictum Grunow in Cleve & Grunow, 1880
- Species Pleurosigma convexum (Grunow in Cleve & Grunow) H. Peragallo, 1891 accepted as Pleurosigma strigosum var. convexum Grunow in Cleve & Grunow, 1880
- Species Pleurosigma crassum Meister, 1932
- Species Pleurosigma crookii Inglis, 1881
- Species Pleurosigma curiosa van den Heuvel in Sterrenburg, 1991
- Species Pleurosigma curvulum (Ehrenberg) Ralfs in Pritchard, 1861 accepted as Navicula curvula Ehrenberg, 1838
- Species Pleurosigma cuspidatum (Cleve) H.Peragallo, 1891
- Species Pleurosigma cuspidatum Cleve accepted as Pleurosigma lanceolatum var. cuspidatum Cleve, 1881
- Species Pleurosigma cuspidatum (Rabenhorst) Ralfs in Pritchard, 1861 accepted as Gyrosigma cuspidata Rabenhorst, 1853
- Species Pleurosigma dalmaticum (Grunow) Grunow in Rodrígues y Femenías, 1889 accepted as Pleurosigma decorum var. dalmatica Grunow in Cleve & Möller, 1878
- Species Pleurosigma decorum W.Smith, 1853
- Species Pleurosigma delicatulum W.Smith, 1852
- Species Pleurosigma densestriata H.P.Gandhi, 1967
- Species Pleurosigma depauperana Manguin in Bourrelly & Manguin, 1952
- Species Pleurosigma diaphanum (Cleve; Cleve) F.W. Mills, 1934 accepted as Gyrosigma diaphanum Cleve, 1894
- Species Pleurosigma diminutum Grunow, 1880
- Species Pleurosigma directum Grunow, 1880
- Species Pleurosigma directumsecundum Karsten, 1905
- Species Pleurosigma distinguendum Hustedt, 1955
- Species Pleurosigma distortum W.Smith, 1852 accepted as Gyrosigma distortum (W.Smith) Griffith & Henfrey, 1856
- Species Pleurosigma diversestriatum Meister, 1934 (1935)
- Species Pleurosigma divisa
- Species Pleurosigma dolosum Mann, 1925
- Species Pleurosigma elegantissimum Castracane, 1886
- Species Pleurosigma ellipticum M. Peragallo in Tempère & Peragallo, 1913
- Species Pleurosigma elongatum W.Smith, 1852
- Species Pleurosigma elongatum Auerswald in litt. ed sched. Rabenhorst, 1863
- Species Pleurosigma eudon
- Species Pleurosigma excelsum Meister, 1937
- Species Pleurosigma exemptum A.Mann, 1925
- Species Pleurosigma eximium (Thwaites) Grunow, 1880 accepted as Schizonema eximium Thwaites, 1848
- Species Pleurosigma exsul Cleve, 1894
- Species Pleurosigma falcatum Donkin, 1861
- Species Pleurosigma fallax Grunow in Cleve & Grunow, 1880
- Species Pleurosigma falx Mann, 1925
- Species Pleurosigma fasciola (Ehrenberg) W.Smith, 1852 accepted as Gyrosigma fasciola (Ehrenberg) J.W.Griffith & Henfrey, 1856
- Species Pleurosigma fasciolum
- Species Pleurosigma febigeri Grunow in Cleve & Möller, 1879
- Species Pleurosigma finmarchicum Cleve in Cleve & Moller, 1882
- Species Pleurosigma fissa Jurilj, 1957
- Species Pleurosigma fluviatile Bening, 1928
- Species Pleurosigma fluviicygnorum J.John, 1983
- Species Pleurosigma formosum W.Smith, 1852
- Species Pleurosigma fossile
- Species Pleurosigma frenguellianum Sunesen, Sterrenburg & Sar, 2014
- Species Pleurosigma frigidum Mann, 1937
- Species Pleurosigma galapagense
- Species Pleurosigma gallicum (Grunow in Van Heurck) H. Peragallo, 1891 accepted as Pleurosigma scalprum var. gallicum Grunow in Van Heurck, 1880-1885
- Species Pleurosigma giganteum Grunow, 1880
- Species Pleurosigma glaciale Cleve, 1883
- Species Pleurosigma glacicolum Simonsen, 1992
- Species Pleurosigma gracile Hustedt, 1955
- Species Pleurosigma gracilentum Rabenhorst, 1861
- Species Pleurosigma gracilescens Grunow in Cleve & Grunow, 1880
- Species Pleurosigma gracillimum Meister, 1932
- Species Pleurosigma grovesii Cleve ex H. Peragallo, 1891
- Species Pleurosigma gruendleri Grunow, 1880
- Species Pleurosigma guarreranum E.A.Sar, F.A.S.Sterrenburg & I.Sunesen, 2013
- Species Pleurosigma hamuliferum Brun, 1889
- Species Pleurosigma hassali
- Species Pleurosigma heros Cleve, 1894
- Species Pleurosigma hibericum De Toni, 1891
- Species Pleurosigma hinzianum Sterrenburg, Sunesen & Sar, 2014
- Species Pleurosigma hippocampus W.Smith, 1852 accepted as Gyrosigma attenuatum (Kützing) Rabenhorst, 1853
- Species Pleurosigma hungaricum Cleve & Brun in Brun & Tempère, 1889
- Species Pleurosigma hyalinum Grunow in Cleve & Grunow, 1880
- Species Pleurosigma hyperborea (Grunow in Cleve & Grunow) H. Peragallo, 1891 accepted as Pleurosigma tenuissimum var. hyperborea Grunow in Cleve & Grunow, 1880
- Species Pleurosigma ibericum H. Peragallo, 1891
- Species Pleurosigma incertum (H. Peragallo) Cleve, 1894 accepted as Rhoicosigma incertum H.Peragallo, 1891
- Species Pleurosigma incertum Forti in Tempère & Peragallo, 1914
- Species Pleurosigma indicum Simonsen, 1974
- Species Pleurosigma inflatum Shadbolt, 1854
- Species Pleurosigma inscriptura M.A.Harper, 2009
- Species Pleurosigma intermedium W.Smith, 1853
- Species Pleurosigma italicum H. Peragallo, 1891
- Species Pleurosigma itaparicanum Zimmermann, 1918
- Species Pleurosigma itium Ricard, 1975
- Variety Pleurosigma itium var. angulosum Ricard, 1975
- Species Pleurosigma japonicum Castracane, 1886
- Species Pleurosigma javanicum H. Peragallo, 1891
- Species Pleurosigma karianum Grunow in Cleve & Grunow, 1880
- Species Pleurosigma karstenii Taylor, 1967
- Species Pleurosigma kerguelense
- Species Pleurosigma kjellmani
- Species Pleurosigma kjellmanii Cleve in Cleve & Grunow, 1880
- Species Pleurosigma kochii Pantocsek, 1892
- Species Pleurosigma kowiense Giffen, 1970
- Species Pleurosigma kuetzingii Grunow, 1860 accepted as Gyrosigma acuminatum (Kützing) Rabenhorst, 1853
- Species Pleurosigma lacustre W.Smith, 1852
- Species Pleurosigma lamprocampum (Ehrenberg) Ralfs in Pritchard, 1861 accepted as Navicula lamprocampa Ehrenberg, 1840
- Species Pleurosigma lanceolatum Donkin, 1858
- Species Pleurosigma latiusculum H. Peragallo, 1891
- Species Pleurosigma latum Cleve, 1880
- Species Pleurosigma lineare Grunow in Cleve & Möller, 1879
- Species Pleurosigma littorale W.Smith, 1852 accepted as Gyrosigma littorale (W.Smith) Griffith & Henfrey, 1856
- Species Pleurosigma longina W. Smith ex Brightwell, 1859
- Species Pleurosigma longinum W.Smith ex Brightwell, 1859
- Species Pleurosigma longissimum Cleve, 1881
- Species Pleurosigma longitudinale Mann, 1937
- Species Pleurosigma longum Cleve, 1873
- Species Pleurosigma lorenzii Grunow, 1860
- Species Pleurosigma macilentum H.Peragallo, 1891
- Species Pleurosigma macrum W.Smith, 1853
- Species Pleurosigma maeoticum Pantocsek, 1902
- Species Pleurosigma major Liu & Chin, 1980
- Species Pleurosigma majus (Grunow) Cleve, 1894 accepted as Pleurosigma speciosum var. majus Grunow in Cleve & Grunow, 1880
- Species Pleurosigma makron Johnston, 1860
- Species Pleurosigma manni Hanna & Grant, 1926
- Species Pleurosigma marinum Donkin, 1858
- Species Pleurosigma maroccanum (Cleve ex H.Peragallo) Cleve, 1894 accepted as Rhoicosigma maroccanum Cleve ex H.Peragallo, 1891
- Species Pleurosigma marylandica (Grunow in Cleve & Grunow) Tempère & Peragallo, 1889-1895 accepted as Pleurosigma affine var. marylandica Grunow in Cleve & Grunow, 1880
- Species Pleurosigma mediterraneum (Cleve in Grunow)
- Species Pleurosigma minutum Donkin, 1858
- Species Pleurosigma minutum Grunow in Cleve & Möller, 1878
- Species Pleurosigma mirabile O'Meara, 1872
- Species Pleurosigma muscicola Krasske, 1948
- Species Pleurosigma naja Meister, 1935
- Species Pleurosigma naviculaceum Brébisson, 1854
- Species Pleurosigma neglectum Karsten, 1899
- Species Pleurosigma neogradense Pantocsek, 1889
- Species Pleurosigma nicobaricum Grunow, 1880
- Species Pleurosigma nodiferum Grunow, 1880
- Species Pleurosigma normanii Ralfs, 1861
- Species Pleurosigma normanii sensu Cleve in Cleve & Grunow, 1880
- Species Pleurosigma notarisii Castracane, 1865
- Species Pleurosigma nubecula W.Smith, 1853 accepted as Pleurosigma intermedium W.Smith, 1853
- Species Pleurosigma obesum A.Mann, 1925
- Species Pleurosigma obliquum Grunow, 1880
- Species Pleurosigma obscurum W.Smith, 1852
- Species Pleurosigma observatoriensis Simonsen, 1992
- Species Pleurosigma obtusatum W.S.Sullivant & Wormley, 1859
- Species Pleurosigma obtusum Mann, 1925
- Species Pleurosigma oceanicum (H. Peragallo) F.W. Mills, 1934 accepted as Rhoicosigma oceanicum f. oceanicum H. Peragallo, 1891
- Species Pleurosigma olympian Terry ex Boyer, 1927
- Species Pleurosigma olympianum Terry ex Tempère & Peragallo, 1909
- Species Pleurosigma olympianum Terry ex Boyer, 1927
- Species Pleurosigma o'mearii (Grunow in Cleve & Grunow) H. Peragallo, 1891
- Species Pleurosigma paradoxum H.Peragallo, 1891
- Species Pleurosigma parkeri Harrison, 1860 accepted as Gyrosigma wormleyi (Sullivant) Boyer, 1922
- Species Pleurosigma parkerii Harrison, 1960
- Species Pleurosigma peisonis Grunow, 1860 accepted as Gyrosigma peisonis (Grunow) Hustedt, 1930
- Species Pleurosigma pelagicum (H.Peragallo) Cleve, 1894 accepted as Pleurosigma acutum var. pelagicum H. Peragallo manus. ex H. Peragallo, 1891
- Species Pleurosigma peragalli
- Species Pleurosigma permagnum Meister, 1932
- Species Pleurosigma perthense J.John, 1983
- Species Pleurosigma plagiostoma Grunow in Cleve & Grunow, 1880
- Species Pleurosigma planctonicum Cleve-Euler, 1952
- Species Pleurosigma planctonicum R.Simonsen, 1974
- Species Pleurosigma planktonica Schrader in Schrader & Fenner, 1976
- Species Pleurosigma polymorphianum Thum
- Species Pleurosigma portoricense Hagelstein, 1939
- Species Pleurosigma praelongum Cleve, 1894
- Species Pleurosigma prisma Mann, 1925
- Species Pleurosigma prolongatum W.Smith, 1852 accepted as Gyrosigma prolongatum (W.Smith) J.W.Griffith & Henfrey, 1856
- Species Pleurosigma pulchrum Grunow, 1860
- Species Pleurosigma pumilum Schumann, 1867
- Species Pleurosigma pusillum Grunow, 1880 accepted as Pleurosigma salinarum (Grunow) Grunow, 1880
- Species Pleurosigma quadratum W.Smith, 1853 accepted as
- Species Pleurosigma quininpiaceii M.Peragallo, 1908
- Species Pleurosigma rahlehense G.Reid
- Species Pleurosigma rectum Donkin, 1858
- Species Pleurosigma reticulatum (Norman) Hustedt, 1955 accepted as Donkinia reticulata Ralfs in Pritchard, 1861
- Species Pleurosigma retusum Zimmermann, 1915
- Species Pleurosigma reversum Gregory, 1857
- Species Pleurosigma rhombeum Grunow, 1880
- Species Pleurosigma rhomboides
- Species Pleurosigma rigens Mann, 1925
- Species Pleurosigma rigidulum Ivanov & Eremenko, 1948
- Species Pleurosigma rigidum W.Smith, 1853
- Species Pleurosigma robustum Grunow, 1880 accepted as Gyrosigma robustum (Grunow) Cleve, 1894
- Species Pleurosigma rostratum Hustedt, 1955
- Species Pleurosigma rushdyense G.Reid
- Species Pleurosigma ryderii M. Peragallo in Tempère & Peragallo, 1909
- Species Pleurosigma sabangi Meister, 1932
- Species Pleurosigma sagitta
- Species Pleurosigma salinarum (Grunow) Grunow, 1880
- Species Pleurosigma sardoum Zanon, 1948
- Species Pleurosigma scalpellum Pritchard
- Species Pleurosigma scalproides Rabenhorst, 1861 accepted as Gyrosigma scalproides (Rabenhorst) Cleve, 1894
- Species Pleurosigma scalprum (Gaillon) Ralfs, 1861 accepted as Gyrosigma scalprum (Gaillon) Sterrenburg, 2007
- Species Pleurosigma scalprum sensu Rabenhorst, 1861-1879
- Species Pleurosigma sciotense Sullivant & Wormley, 1859
- Species Pleurosigma secundum Karsten, 1905
- Species Pleurosigma siberica (Grunow) Cardinal, Poulin & Berard-Therriault, 1980
- Species Pleurosigma signatum Voigt, 1969
- Species Pleurosigma simile Grunow, 1880
- Species Pleurosigma simonsenii Hasle, 1990
- Species Pleurosigma simplex Ricard, 1975
- Species Pleurosigma simum (Ehrenberg; Ehrenberg) Ralfs in Pritchard, 1861 accepted as Navicula sima Ehrenberg, 1845
- Species Pleurosigma sinense
- Species Pleurosigma sinensis (Ehrenberg) Ralfs, 1861 accepted as Navicula sinensis Ehrenberg, 1847
- Species Pleurosigma sinuosum (Ehrenberg) Ralfs in Pritchard, 1861 accepted as Navicula sinuosa Ehrenberg, 1840
- Species Pleurosigma smithianum Castracane, 1886
- Species Pleurosigma smithii Grunow, 1860
- Species Pleurosigma speciosum W.Smith
- Species Pleurosigma speciosum sensu Meunier, 1910
- Species Pleurosigma spectabile Grunow, 1891
- Species Pleurosigma spectabilis Grunow ex Moller, 1868, 1881
- Species Pleurosigma spectrosum Barkas, 1867
- Species Pleurosigma spenceri (Bailey ex Quekett) W.Smith, 1856
- Species Pleurosigma spencerii Grunow
- Species Pleurosigma spinulosum Pantocsek & Greguss in Greguss, 1913
- Species Pleurosigma staurolineatum Karsten, 1899
- Species Pleurosigma staurophorum Grunow, 1880 accepted as Costasigma staurophorum (Grunow) G.Reid, 2012
- Species Pleurosigma sterrenburgii Stidolph, 1993
- Species Pleurosigma stidolphii Sterrenburg, 1991
- Species Pleurosigma striatum Schumann, 1867
- Species Pleurosigma strigilis W.Smith, 1852 accepted as Gyrosigma strigilis (W.Smith) J.W.Griffin & Henfrey, 1856
- Species Pleurosigma strigosum W.Smith, 1852
- Species Pleurosigma stuxbergii Cleve & Grunow, 1880
- Species Pleurosigma subhyalinum Hustedt & Aleem, 1951
- Species Pleurosigma subrecta (Cleve in Cleve & Grunow) Cleve, 1894 accepted as Pleurosigma subrectum Cleve, 1880
- Species Pleurosigma subrectum Cleve, 1880
- Species Pleurosigma subrectum Grunow, 1860
- Species Pleurosigma subrigidum Grunow, 1880
- Species Pleurosigma subsalina Peragallo
- Species Pleurosigma subsalinum H.Peragallo, 1891 accepted as Pleurosigma spenceri var. subsalinum H. Peragallo, 1891
- Species Pleurosigma subsalsum Wislouch & Kolbe, 1916
- Species Pleurosigma subtile (Brébisson in Kutzing) Ralfs in Pritchard, 1861 accepted as Navicula subtilis Brebisson in Kutzing, 1849
- Species Pleurosigma subtilissimum T.Marsson, 1900
- Species Pleurosigma sulcatum Grunow, 1880 accepted as Gyrosigma fasciola var. sulcatum (Grunow) Cleve, 1894
- Species Pleurosigma suluense Mann, 1925
- Species Pleurosigma sumatricum H. Peragallo, 1891
- Species Pleurosigma tahitense Castracane, 1886
- Species Pleurosigma tahitensis Witt, 1873
- Species Pleurosigma tahitianum Ricard, 1975
- Species Pleurosigma temperei (Cleve) M.Peragallo, 1903 accepted as Gyrosigma temperei Cleve, 1893
- Species Pleurosigma tenerum E. Jorgensen, 1905
- Species Pleurosigma tenuiforme C.H. von Quillfeldt, 2000
- Species Pleurosigma tenuirostris Grunow in Cleve & Grunow, 1880
- Species Pleurosigma tenuissimum W.Smith, 1853 accepted as Gyrosigma tenuissimum (W.Smith) Griffith & Henfrey, 1856
- Species Pleurosigma terryanum H.Peragallo, 1891
- Species Pleurosigma thaitiense Castracane, 1886
- Species Pleurosigma thumii (Castracane ex H. Peragallo) De Toni, 1891 accepted as Pleurosigma nubecula var. thumii Castracane ex H. Peragallo, 1891
- Species Pleurosigma thumii Cleve ex H. Peragallo, 1891
- Species Pleurosigma thuringicum (Kützing) Ralfs in Pritchard, 1861 accepted as Navicula thuringica Kützing, 1844
- Species Pleurosigma tortuosum Cleve, 1881
- Species Pleurosigma transversale W.Smith accepted as Pleurosigma naviculaceum Brébisson, 1854
- Species Pleurosigma transylvanicum Pantocsek, 1892
- Species Pleurosigma tropicum Grunow, 1860
- Species Pleurosigma umbilicatum Cleve, 1894
- Species Pleurosigma vairaense Ricard, 1975
- Species Pleurosigma validum Shadbolt, 1854
- Species Pleurosigma virginiacum H.L. Smith, 1877
- Species Pleurosigma virginica Peticolas, 1877
- Species Pleurosigma vitrea
- Species Pleurosigma vitreum Cleve, 1880
- Species Pleurosigma vitreum sensu Meunier, 1910
- Species Pleurosigma wansbecki
- Species Pleurosigma wansbeckii Donkin, 1858 accepted as Gyrosigma wansbeckii (Donkin) Cleve, 1894
- Species Pleurosigma weissflogii (Grunow in Cleve & Grunow) Cleve, 1894 accepted as Rhoicosigma weissflogii var. weissflogii Grunow in Cleve & Grunow, 1880
- Species Pleurosigma wigginsianum Hendey, 1971
- Species Pleurosigma williamsii G.Reid
- Species Pleurosigma wormleyi W.S.Sullivant, 1859
- Genus Rhoicosigma A. Grunow, 1867 (4)
- Genus Toxonidea A.S. Donkin, 1858 (3)
- Genus Toxonidisigma Lobban & G. Reid, 2018 (2)
- Family Scolioneidaceae
- Family Scoliotropidaceae Mersechk. (6)
- Family Sellaphoraceae Mereschkowsky, 1902 (74)
- Family Stauroneidaceae D.G. Mann, 1990 (150)
- Order Rhopalodiales (37)
- Order Surirellales (174)
- Order Thalassiophysales (105)
- Superorder Bacillariophycidae incertae sedis (32)
- Superorder Eunotiophycanae (293)
- Subclass Coscinodiscophycidae (877)
- Subclass Fragilariophycidae (483)
- Order Centrales
