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)
- Subclass Coscinodiscophycidae (877)
- Subclass Fragilariophycidae (483)
- Superorder Fragilariophycanae (483)
- Order Ardissoneales (1)
- Order Climacospheniales (2)
- Order Cyclophorales (8)
- Order Fragilariales (377)
- Family Fragilariaceae Greville, 1833 (377)
- Genus Adoneis G.W. Andrews & P. Rivera, 1987 (1)
- Genus Andrewsiella T.Jurkschat, 1997 †
- Genus Asterionella A.H. Hassall, 1850 (4)
- Genus Asterionellopsis F.E. Round in F.E. Round, R.M. Crawford & D.G. Mann, 1990 (2)
- Genus Asteroplanus C. Gardner & R.M. Crawford in R.M. Crawford & C. Gardner, 1997
- Genus Bleakeleya F.E. Round in F.E. Round, R.M. Crawford & D.G. Mann, 1990
- Genus Brandinia L.F. Fernandes in Fernandes, Procopiak & Portinho, 2007
- Genus Brassierea M.K.Hein & B.M.Winsborough, 1999
- Genus Castoridens Ashworth, Chunlian Li & Witkowski, 2016 (2)
- Genus Catacombas D.M. Williams & F.E. Round, 1986
- Genus Centronella M. Voigt, 1902
- Genus Ceratoneis C.G. Ehrenberg, 1839 accepted as Cylindrotheca L. Rabenhorst, 1859 (3)
- Genus Cratericulifera Chunlian Li, Witkowski & Ashworth, 2016 (2)
- Genus Ctenophora (Grunow) D.M.Williams & Round, 1986 (2)
- Genus Ctenophora A. Grunow, 1862
- Genus Desikaneis A.K.S.K. Prasad in A.K.S.K. Prasad & R.J. Livingston, 1993 (1)
- Genus Diatoma J.B.M. Bory de Saint-Vincent, 1824 (13)
- Genus Distrionella D.M. Williams, 1990 (2)
- Genus Falcula M. Voigt, 1960 (1)
- Genus Fossula G.R. Hasle, E.E. Syvertsen & C.H. von Quillfeldt, 1996 accepted as Fossulaphycus Blanco, 2020
- Genus Fossulaphycus Blanco, 2020 (1)
- Genus Fragilaria H.C. Lyngbye, 1819 (100)
- Genus Fragilariforma D.M. Williams & F.E. Round, 1988 (8)
- Genus Frankophila H. Lange-Bertalot, 1997 (3)
- Genus Gedaniella Chunlian Li, Witkowski & Ashworth, 2018 (4)
- Genus Grammonema C.A. Agardh, 1832 (2)
- Genus Hannaea R. Patrick in R. Patrick & C.W. Reimer, 1966 (15)
- Genus Hendeyella Ashworth, Witkowski & Chunlian Li, 2016 (4)
- Genus Hyaloneis M.C. Amspoker, 2008
- Genus Hyalosynedra D.M. Williams & F.E. Round, 1986 (7)
- Genus Koernerella C.S. Lobban & E.C. Theriot in Lobban et al., 2011
- Genus Martyana F.E. Round in F.E. Round, R.M. Crawford & D.G. Mann, 1990
- Genus Meridion C.A. Agardh, 1824 (3)
- Genus Neofragilaria D.M. Williams & F.E. Round, 1988 accepted as Fragilariforma D.M. Williams & F.E. Round, 1988
- Genus Neosynedra D.M. Williams & F.E. Round, 1986
- Genus Opephora P. Petit, 1888 (6)
- Genus Perideraion C.S. Lobban & R.W. Jordan in Lobban et al., 2011
- Genus Plagiostriata S.Sato & L.K.Medlin, 2009 (2)
- Genus Podocystis J.W. Bailey, 1854 (1)
- Genus Popovskayella Kulikovskiy & Lange-Bertalot, 2015
- Genus Porannulus P.B. Hamilton & M. Poulin in Hamilton, Poulin, Yang & Kloser, 1998
- Genus Psammosynedra F.E. Round, 1993
- Genus Psammotaenia Ashworth, Chunlian Li & Witkowski, 2016 (1)
- Genus Pseudo-eunotia A. Grunow in H. Van Heurck, 1881 (1)
- Genus Pseudofalcula F. Gomez, Lu Wang & Senjie Lin, 2018 (1)
- Genus Pseudostaurosira D.M. Williams & F.E. Round, 1988 (59)
- Genus Pteroncola R.W. Holmes & D.A. Croll, 1984 (1)
- Genus Punctastriata D.M. Williams & F.E. Round, 1988 (4)
- Genus Reimerothrix A.K.S.K. Prasad in Prasad, A.K. S.K., Nienow, J.A. & Riddle, K.A., 2001
- Genus Rimoneis M. Garcia, 2010
- Genus Sarcophagodes E.A. Morales, 2002 (5)
- Genus Serratifera Ashworth, Chunlian Li & Witkowski, 2016 (2)
- Genus Stauroforma R.J. Flower, V.J. Jones & F.E. Round, 1996 (1)
- Genus Staurosira C.G. Ehrenberg, 1843 (16)
- Genus Staurosirella D.M. Williams & F.E. Round, 1987 (26)
- Genus Synedra C.G. Ehrenberg, 1830 (35)
- Species Synedra acicularis Kützing, 1844
- Species Synedra acicularis W.Smith, 1853
- Species Synedra actinastroides Lemmermann, 1900 accepted as Nitzschia holsatica Hustedt, 1930
- Species Synedra actinonelloides Otto Müller in Schmidle, 1902
- Species Synedra acula Kützing, 1844
- Species Synedra acus Kützing, 1844 accepted as Synedra radians var. radians Kützing, 1844
- Species Synedra acus (Krieger) Skabichevskii, 1960 accepted as Synedra acus var. ostenfeldii Krieger, 1927
- Species Synedra acus Ehrenberg, 1854
- Species Synedra acusaprilina Morkin ex De Notaris, 1853
- Species Synedra acuta Ehrenberg, 1843
- Species Synedra adeliae Manguin, 1957
- Species Synedra adeliae Manguin, 1960
- Species Synedra aequalis (Kützing) Kützing
- Species Synedra affinis Kützing, 1844 accepted as Tabularia fasciculata (C.Agardh) D.M.Williams & Round, 1986
- Species Synedra affinis sensu Tempère & Peragallo, 1909
- Species Synedra aggregata Brebisson ex Rabenhorst, 1858
- Species Synedra alaskana Patrick & Freese, 1961
- Species Synedra allansonii Cholnoky, 1958
- Species Synedra allorgei Manguin, 1942
- Species Synedra alpina Naegeli ex Kützing, 1849 accepted as Eunotia naegelii Migula, 1907
- Species Synedra amoyensis Skvortzov, 2012
- Species Synedra amphicephala Kützing, 1844 accepted as Fragilaria amphicephaloides Lange-Bertalot, 2013
- Species Synedra amphicephala sensu H.L. Smith, 1874-1879
- Species Synedra amphicoryna Ehrenberg, 1860
- Species Synedra amphilepta Ehrenberg, 1854
- Species Synedra amphioxys Ehrenberg, 1856
- Species Synedra amphirhynchus Ehrenberg, 1843 accepted as Ulnaria amphirhynchus (Ehrenberg) Compère & Bukhtiyarova, 2006
- Species Synedra anguinea Boyer, 1920
- Species Synedra angusta Østrup in Héribaud et al., 1920
- Species Synedra angustata Kützing, 1844
- Species Synedra angustissima Woloszynska, 1921
- Species Synedra antarctica M. Peragallo, 1921
- Species Synedra antarctica Heiden & Kolbe, 1928
- Species Synedra apiculata Rabenhorst, 1853
- Species Synedra arctica O'Meara, 1874
- Species Synedra arctica Grunow, 1862
- Species Synedra arcuata (Ostenfeld) A.Cleve
- Species Synedra arcuata Naegeli in Kutzing, 1849
- Species Synedra arcuata Wigand, 1860
- Species Synedra arcus Kützing, 1844 accepted as Tabularia arcus (Kützing) Williams,
- Species Synedra arcus sensu Lagerstedt, 1876
- Species Synedra arguinensis Skvortzov, 2012
- Species Synedra armoricana Kützing, 1844
- Species Synedra armoricana H.Peragallo, 1915
- Species Synedra articulata Crouan ex Maze & Schramm, 1880-1887
- Species Synedra asterionelloides Otto Müller ex Schmidle, 1902
- Species Synedra atlantica Castracane, 1886
- Species Synedra atomus (Kützing) Nägeli, 1849 accepted as Amphora atomus Kützing, 1844
- Species Synedra auriculata Karsten, 1905
- Species Synedra australis Ehrenberg, 1840
- Species Synedra austriaca Grunow, 1881
- Species Synedra bacillaris (Grunow) Hustedt, 1932 accepted as Synedra crystallina var. bacillaris Grunow, 1877
- Species Synedra baculus Gregory, 1857
- Species Synedra balatonis Pantocsek, 1902
- Species Synedra balthica Ehrenberg, 1832
- Species Synedra baltica Ehrenberg, 1832
- Species Synedra bananaensis Kufferath, 1956
- Species Synedra barbatula Kützing, 1844 accepted as Tabularia barbatula (Kützing) D.M.Williams & Round, 1986
- Species Synedra barrowiana Patrick & Freese, 1961
- Species Synedra berolinensis Lemmermann, 1900 accepted as Belonastrum berolinensis (Lemmermann) Round & Maidana, 2001
- Species Synedra biasolettiana Kützing, 1844
- Species Synedra biceps Kützing, 1844 accepted as Ulnaria biceps (Kützing) P.Compère, 2001
- Species Synedra biceps W.Smith, 1853
- Variety Synedra biceps var. arcus (Brebisson in Brebisson & Godey) Kützing, 1849 accepted as Exilaria arcus Brebisson in Brebisson & Godey, 1835
- Variety Synedra biceps var. distenta Fritsch & Rich, 1929
- Variety Synedra biceps var. recta Kützing, 1844
- Forma Synedra biceps f. biceps Kützing, 1844
- Forma Synedra biceps f. robusta Rabenhorst, 1864
- Species Synedra bicurvata Biene ex Rabenhorst, 1864
- Species Synedra biharensis Hajós, 1959
- Species Synedra biharensis Pantocsek, 1889
- Species Synedra bilunaris Ehrenberg, 1832 accepted as Eunotia bilunaris (Ehrenberg) Schaarschmidt, 1880
- Species Synedra binodis (Ehrenberg) Chang & Steinberg, 1988 accepted as Fragilaria construens var. binodis Stockmayer, 1909
- Species Synedra bipes Roll, 1926
- Species Synedra brebissonii W. Smith Collection
- Species Synedra brebissonii (Kützing) De Toni, 1892 accepted as Sigmatella brebissonii Kützing, 1849
- Species Synedra brébissonii (Kützing) Rabenhorst, 1853 accepted as Sigmatella brebissonii Kützing, 1849
- Species Synedra bremiana Pantocsek, 1889
- Species Synedra brevis Ehrenberg, 1848
- Species Synedra brockmanni Hustedt, 1932
- Species Synedra calva
- Species Synedra calva Castracane, 1880
- Species Synedra campyla Hilse in Rabenhorst, 1861
- Species Synedra camtschatica Grunow, 1862
- Species Synedra capensis Grunow in Van Heurck, 1881
- Species Synedra capilla Carter & Denny, 1992
- Species Synedra capillaris Grunow, 1877
- Species Synedra capitata Ehrenberg, 1836 accepted as Ulnaria capitata (Ehrenberg) P.Compère, 2001
- Species Synedra capitellata Grunow, 1881 accepted as Fragilaria recapitellata H. Lange-Bertalot & D. Metzeltin, 2009
- Species Synedra capitulata Castracane, 1886
- Species Synedra capucina Stoermer & Kreis, 1978
- Species Synedra caroliprincipis Istvanffi (Schaarschmidt), 1881
- Species Synedra chandolensis H.P.Gandhi, 1964 accepted as Tabularia chandolensis (Gandhi) A. Vigneshwaran, D.M. Williams & B. Karthick
- Species Synedra charcotii M. Peragallo, 1921
- Species Synedra chaseana (Thomas) Boyer, 1927 accepted as Synedra ulna var. chaseana Thomas, 1886
- Species Synedra chasei B. W. Thomas in Walker & Chase, 1886
- Species Synedra chungii Skvortzov, 2012
- Species Synedra circularis Savitsch & Balkaschina, 1928
- Species Synedra clava Witt, 1873
- Species Synedra clavata Greville, 1865
- Species Synedra closterioides Grunow, 1881
- Species Synedra columber (Brun) Kanaya, 1963
- Species Synedra commutata Grunow
- Species Synedra commutata sensu De Toni, 1892
- Species Synedra constricta Kützing, 1844
- Species Synedra constricta Ehrenberg, 1848
- Species Synedra cornigera Grunow, 1877
- Species Synedra coronata Kirchenpauer, 1863
- Species Synedra costata Hajós, 1959
- Species Synedra cretae Sauvage ex Tempère & Peragallo, 1913
- Species Synedra cristallina
- Species Synedra crotonensis Grunow
- Species Synedra crotonensis (Kitton) Cleve & Möller, 1878
- Species Synedra crystallina (C.Agardh) Kützing, 1844
- Species Synedra crystallina Grove & Sturt, 1886
- Species Synedra cuneata H.P. Gandhi, 1998 accepted as Synedra gandhii Guiry & Karthick, 2020
- Species Synedra cuneata (Lyngbye) Ehrenberg
- Species Synedra cuneata Grunow, 1867
- Species Synedra cunningtonii G.S.West, 1907
- Species Synedra curvata Proschkina-Lavrenko, 1951
- Species Synedra curvata Østrup, 1918 (1920)
- Species Synedra curvata Ehrenberg in Ralfs in Pritchard, 1861
- Species Synedra curvula Kützing, 1844
- Species Synedra cyclopum Brutschy, 1922
- Species Synedra cymbelliformis A.Schmidt, 1874
- Species Synedra dalmatica Kützing, 1844
- Species Synedra danica Kützing, 1844
- Species Synedra debilis Kützing, 1844
- Species Synedra decipiens Cleve & Grunow in Cleve & Moller, 1877
- Species Synedra decipiens Cleve & Grunow in Grunow, 1877
- Species Synedra decloitrei Amossé, 1970
- Species Synedra deformis W. Smith, 1856
- Species Synedra delicatissima W.Smith, 1853 accepted as Ulnaria delicatissima (W.Smith) M.Aboal & P.C.Silva, 2004
- Species Synedra delicatissima Schroter, 1896
- Species Synedra delicatula Ant.Mayer, 1919
- Species Synedra demerarae Grunow, 1881
- Species Synedra dissipata Kützing, 1844 accepted as Nitzschia dissipata (Kützing) Rabenhorst, 1860
- Species Synedra distinguenda Hustedt, 1932
- Species Synedra doliolus Wallich, 1860 represented as Fragilariopsis doliolus (Wallich) Medlin & P.A.Sims, 1993
- Species Synedra dorsiventralis Otto Müller, 1910
- Species Synedra dubia Carruthers, 1864
- Species Synedra dubia Grunow in Van Heurck, 1881
- Species Synedra dubravicensis Pantocsek, 1892
- Species Synedra duhemi Hanna & Grant, 1926
- Species Synedra ehrenbergii Kützing, 1844
- Species Synedra elegans Ehrenberg, 1854
- Species Synedra elongatum Stoermer & Kreis, 1978
- Species Synedra entomon Ehrenberg, 1841
- Species Synedra exilis Kutzing ex F. W. Mills, 1935
- Species Synedra falcata Brébisson ex Kützing, 1849
- Species Synedra falcata Rabenhorst, 1864
- Species Synedra fallax Grunow in Van Heurck, 1881
- Species Synedra famelica Kützing, 1844 accepted as Fragilaria famelica (Kützing) Lange-Bertalot, 1980
- Species Synedra familiaris Kützing, 1844
- Species Synedra fasciculata (Agardh) Kützing accepted as Tabularia fasciculata (C.Agardh) D.M.Williams & Round, 1986
- Species Synedra fasciculata Ehrenberg, 1832
- Species Synedra fasciolaris Eichwald, 1849
- Species Synedra fastuosa
- Species Synedra fibula W. Smith, 1859
- Species Synedra fibula Brun, 1896
- Species Synedra filiformis J.R.Carter & P.Denny, 1987
- Species Synedra filiformis Grunow, 1880
- Species Synedra fimbriata Castracane, 1886
- Species Synedra fisherensis Bond, 1968
- Species Synedra flexuosa Brébisson ex Kützing, 1846 accepted as Eunotia flexuosa (Brébisson ex Kützing) Kützing, 1849
- Species Synedra flexuosa Ehrenberg, 1853
- Species Synedra fluviatilis
- Species Synedra fontinalis W. Smith, 1857
- Species Synedra formosa Hantzsch, 1863 accepted as Ardissonea formosa (Hantzsch) Grunow
- Species Synedra forta Brébisson ex W. Smith Collection
- Species Synedra fragilariaeformis Fritsch & Rich, 1924
- Species Synedra fragilarioides Hargraves & Guillard, 1974
- Species Synedra fragilis Manguin, 1957
- Species Synedra frauenfeldii Grunow
- Species Synedra frigida Zeller in Rabenhorst, 1863
- Species Synedra frustulum Kützing, 1844
- Species Synedra fuchsii (Pantocsek) Schrader, 1969
- Species Synedra fulgens (Greville) W.Smith, 1853
- Species Synedra fusidioides Rabenhorst, 1853
- Species Synedra fusidium Kützing, 1844
- Species Synedra gaillonii (Bory de Saint-Vincent) Ehrenberg, 1830 accepted as Tabularia gaillonii (Bory de Saint-Vincent) Bukhtiyarova, 1995
- Species Synedra galioni
- Species Synedra gallionii
- Species Synedra gandhii Guiry & Karthick, 2020
- Species Synedra gausii
- Species Synedra gaussi Heiden, 1928 accepted as Nitzschia marina Grunow, 1880
- Species Synedra gaussii
- Species Synedra gelida Frenguelli, 1960
- Species Synedra gelida (M. Peragallo) Mann, 1937 accepted as Thalassionema gelida var. gelida M. Peragallo, 1921
- Species Synedra geminata (Grunow)
- Species Synedra gibba Ehrenberg, 1843
- Species Synedra gibbosa Ralfs, 1861
- Species Synedra gigantea Lobarzewsky, 1840
- Species Synedra gigantea Ehrenberg, 1840
- Species Synedra gloiophila Grunow in Van Heurck, 1881 accepted as Fragilaria gloiophila (Grunow) Van de Vijver, Ector, T.M.Schuster & J.Walter, 2020
- Species Synedra gomphonema Janisch & Rabenhorst, 1863
- Species Synedra goulardi Brébisson
- Species Synedra goulardii Brébisson ex Cleve & Grunow, 1880 accepted as
- Species Synedra gracilis Kützing
- Species Synedra gracilis Brun, 1880
- Species Synedra gracilis sensu W. Smith, 1856
- Species Synedra gracilis sensu Lagerstedt, 1876
- Species Synedra gracillima W. Smith
- Species Synedra gracillima Rabenhorst, 1853
- Species Synedra grandis Mereschkowsky, 1902 accepted as Tabularia grandis (Mereschkowsky) M.Aboal, 2003
- Species Synedra groveii Grunow, 1889
- Species Synedra hamata W.Smith, 1853
- Species Synedra hantzschiana Sournia, 1963
- Species Synedra hartii Cholnoky, 1963
- Species Synedra hastata Rabenhorst, 1864
- Species Synedra heidenii Simonsen, 1992
- Species Synedra helvetica Brutschy, 1922
- Species Synedra hemicyclus Ehrenberg, 1840
- Species Synedra hennedyana Gregory, 1857 accepted as Toxarium hennedyanum (Gregory) Pelletan, 1889
- Species Synedra hennedyana Karsten, 1899
- Species Synedra hensenii (Schütt) Coupin, 1930 accepted as Rhizosolenia hensenii Schütt, 1900
- Species Synedra hiemalis Anonymous, 1912 (1913)
- Species Synedra holsatiae Hensen, 1887
- Species Synedra homostriata Hohn, 1961
- Species Synedra hyalina Provazek, 1900
- Species Synedra hyalina M. Peragallo in Tempère & Peragallo, 1908
- Species Synedra hybrida (Grunow in Van Heurck) F.W. Mills, 1935 accepted as Synedra affinis f. hybrida Grunow in Van Heurck, 1881
- Species Synedra hyperborea Grunow, 1884 accepted as Synedropsis hyperborea (Grunow) G.R.Hasle, L.K.Medlin & E.E.Syvertsen, 1994
- Species Synedra imperfecta Cleve-Euler, 1939
- Species Synedra inaequalis H.Kobayasi, 1964
- Species Synedra incerta Mereschkowsky, 1902
- Species Synedra incisa Boyer, 1920
- Species Synedra incisa Rabenhorst, 1847
- Species Synedra incurva Ehrenberg, 1844 (1845)
- Species Synedra indica F.J.R.Taylor, 1967
- Species Synedra inflata Heiden, 1900 accepted as Staurosira inflata (Heiden) A.Rusanov, Ács, E. Morales & Ector in Rusanov et al., 2018
- Species Synedra inflexa Eichwald, 1847
- Species Synedra intermedia Grunow in Van Heurck, 1881
- Species Synedra interrupta Auerswald in Rabenhorst, 1855
- Species Synedra investiens W.Smith, 1856 accepted as Tabularia investiens (W.Smith) D.M.Williams & F.E.Round, 1986
- Species Synedra isabelae Patrick, 1970
- Species Synedra italica Rabenhorst, 1853
- Species Synedra japonica Skvortzow, 1931
- Species Synedra japonica Meister, 1913
- Species Synedra jogensis Gandhi, 1966
- Species Synedra joursacensis Héribaud-Joseph, 1903
- Species Synedra jouseana V.S.Sheshukova-Poretzkaya
- Species Synedra juliana De Notaris emend Granetti, 1968
- Species Synedra juliana De Notaris, 1842-1868
- Species Synedra juranyi Pantocsek, 1892
- Species Synedra kamschatica
- Species Synedra kamtschatica
- Species Synedra kamtschatica Grunow in Cleve & Grunow, 1880
- Species Synedra karcheri Nemoto, 1956
- Species Synedra kashyapiens Misra, 1956
- Species Synedra kerguelensis
- Species Synedra kinkeri (Pantocsek) Jurilj, 1957 accepted as Clavicula kinkerii Pantocsek, 1892
- Species Synedra koganii Mikhailov, 1986
- Species Synedra koreana Skvortzow, 1931
- Species Synedra kullaaensis Tynni, 1994
- Species Synedra laevigata Grunow accepted as Hyalosynedra laevigata (Grunow) Williams & Round, 1986
- Species Synedra laevis Kützing, 1844
- Species Synedra laevis Ehrenberg, 1843
- Species Synedra laevis Kützing, 1844
- Species Synedra laevissima
- Species Synedra lanceolata Kützing, 1844 accepted as Ulnaria lanceolata (Kützing) P.Compère, 2001
- Species Synedra lancettula (Grunow) A. Cleve-Euler, 1949 accepted as Synedra lancettula Grunow in Van Heurck, 1881
- Species Synedra lancettula Grunow in Van Heurck, 1881
- Species Synedra lata (Giffen) A.Witkowski, 2000
- Species Synedra lemmermanni W. & G. S. West, 1906
- Species Synedra lenzi Krasske, 1939
- Species Synedra lepida Grunow in Van Heurck, 1881
- Species Synedra levis
- Species Synedra libyca Kützing, 1849
- Species Synedra licenti Skvortzow, 1935
- Species Synedra limnetica Lemmermann, 1900
- Species Synedra linea Ehrenberg, 1844
- Species Synedra linearis Ehrenberg, 1846
- Species Synedra lineata Ralfs in Pritchard, 1861
- Species Synedra lismorensis Playfair, 1915
- Species Synedra longiceps Ehrenberg, 1845
- Species Synedra longissima W.Smith, 1853 accepted as Ulnaria longissima (W.Smith) Van de Vijver & D.M.Williams, 2022
- Species Synedra lunaris Ehrenberg, 1832 accepted as Eunotia bilunaris (Ehrenberg) Schaarschmidt, 1880
- Species Synedra lunaris W. Smith, 1853
- Species Synedra lunula Ehrenberg, 1870
- Species Synedra macroptera Ehrenberg, 1854
- Species Synedra maeotica Pantocsek
- Species Synedra magna A.M. Edwards in Stodder, 1861
- Species Synedra marina Grunow in Cleve & Möller, 1878
- Species Synedra martensiana Kützing, 1844
- Species Synedra mazamaensis Sovereign, 1958
- Species Synedra merluzae Frenguelli & Orlando, 1959
- Species Synedra mesocampa Brébisson in Kützing, 1849
- Species Synedra mesolepta Kützing, 1844
- Species Synedra minuscula Grunow, 1881 accepted as Fragilaria famelica (Kützing) Lange-Bertalot, 1980
- Species Synedra minuta Mereschkowsky, 1902
- Species Synedra minutissima Kützing, 1844
- Species Synedra minutissima W. Smith, 1853
- Species Synedra miocenica Schrader, 1976
- Species Synedra monodi Guermeur, 1954
- Species Synedra montana Krasske ex Hustedt, 1932
- Species Synedra multifasciata Kutzing in litt.
- Species Synedra muscicola Kützing, 1844
- Species Synedra mystica Archibald, 1971
- Species Synedra nana F.Meister, 1912
- Species Synedra neapolitana (Rabenhorst) Rabenhorst, 1864 accepted as Falcatella neapolitana Rabenhorst, 1853
- Species Synedra netronoides Hohn & Hellerman, 1963
- Species Synedra nipponica Skvortzow, 1936
- Species Synedra nitzschii Rabenhorst, 1853
- Species Synedra nitzschioides Grunow, 1862 accepted as Thalassionema nitzschioides (Grunow) Mereschkowsky, 1902
- Species Synedra nitzschioides Maly, 1895
- Species Synedra normaniana Greville, 1862
- Species Synedra notarisii Castracane, 1866
- Species Synedra notata Kützing, 1844
- Species Synedra nyansae G.S.West, 1907
- Species Synedra oamaruensis Schrader, 1969
- Species Synedra obtusa W.Smith, 1853
- Species Synedra ossiformis Taylor, 1967
- Species Synedra ostenfeldii (Krieger) Cleve-Euler ex Stalberg, 1940 accepted as Fragilaria ostenfeldii (Willi Krieg.) Van de Vijver, Alexson & Reavie in Van de Vijver et al., 2020
- Species Synedra oxyrhynchus Kützing, 1844 accepted as
- Species Synedra pachycephala Brébisson & Kützing in Kützing, 1846
- Species Synedra pachycephala Ralfs in Pritchard, 1861
- Species Synedra pacifica A.M. Edwards in Stodder, 1861
- Species Synedra palea Kützing, 1844 accepted as Nitzschia palea (Kützing) W.Smith, 1856
- Species Synedra paleacea Ehrenberg, 1840
- Species Synedra paludosa Meister, 1912
- Species Synedra parasitica (W.Smith) Hustedt, 1930 accepted as Pseudostaurosira parasitica (W.Smith) Morales, 2003
- Species Synedra parva Kützing
- Species Synedra parvula Kützing, 1844 accepted as Frustulia parvula Kützing, 1833 (1834)
- Species Synedra pelagica Hendey, 1937
- Species Synedra pelagica Cleve-Euler, 1937
- Species Synedra perexigua Cleve-Euler, 1953
- Species Synedra perminuta Grunow in Van Heurck, 1881 accepted as Fragilaria perminuta (Grunow in Van Heurck) Lange-Bertalot in Krammer & Lange-Bertalot, 2000
- Species Synedra perpusilla Kützing, 1844
- Species Synedra phantasma Hohn, 1966 represented as Fragilaria phantasma (M.H.Hohn) C.E.Wetzel, Potapova & D.M.Williams, 2022
- Species Synedra philippinarum Castracane, 1886
- Species Synedra planktonica Hains & Sebring, 1981
- Species Synedra platensis Frenguelli, 1938 accepted as Tabularia platensis (Frenguelli) Sar & Sala, 2009
- Species Synedra pliocenica Héribaud & M. Peragallo in Héribaud, 1902
- Species Synedra polymorpha (Pantocsek & Grunow) Schrader, 1969 accepted as Clavicula polymorpha var. polymorpha Grunow & Pantocsek in Pantocsek, 1886
- Species Synedra porrecta Rabenhorst, 1853
- Species Synedra praemorsa Ehrenberg, 1843
- Species Synedra provincialis Grunow accepted as Neosynedra provincialis (Grunow) D.M.Williams & Round, 1986
- Species Synedra pseudogoulardii Manguin, 1964
- Species Synedra puellaris Messikommer, 1945
- Species Synedra pulchella (Ralfs ex Kützing) Kützing, 1844 accepted as Ctenophora pulchella (Ralfs ex Kützing) D.M.Williams & Round, 1986
- Species Synedra pulchella Kützing, 1844
- Species Synedra pulcherrima Hantzsch in Rabenhorst, 1863
- Species Synedra punctata Østrup, 1913
- Species Synedra pusilla Kützing, 1844
- Species Synedra putealis O'Meara, 1875
- Species Synedra putrida Cohn, 1854
- Species Synedra quadrangula Kützing, 1844
- Species Synedra radians Kützing, 1844 accepted as Fragilaria radians (Kützing) D.M.Williams & Round, 1987
- Species Synedra radians W. Smith, 1853
- Species Synedra radiosa Gordienko, 1929
- Species Synedra ramesi Héribaud-Joseph, 1903
- Species Synedra recava Hohn, 1961
- Species Synedra regalis Taylor, 1967
- Species Synedra reinboldii Van Heurck, 1909
- Species Synedra rennellensis Foged, 1957
- Species Synedra revalensis sensu W. & G. S. West, 1906
- Species Synedra revaliensis Lemmermann, 1906
- Species Synedra revaliensis Lemmerman in West & West, 1906
- Species Synedra ridica Hohn & Hellerman, 1966
- Species Synedra robusta Ralfs ex Pritchard, 1861 accepted as Ardissonea robusta (Ralfs ex Pritchard) De Notaris, 1871
- Species Synedra romana (Rabenhorst) Rabenhorst, 1864 accepted as Falcatella romana Rabenhorst, 1853
- Species Synedra rosenkrantzii Foged, 1958
- Species Synedra rostrata Pantocsek, 1902
- Species Synedra rostrata Meister, 1913
- Species Synedra rostrata (Hantzsch) Hustedt in Schmidt et al., 1914 accepted as Toxarium rostratum Hantzsch, 1863
- Species Synedra rostrata Ehrenberg, 1854
- Species Synedra rostrata (Hantzsch) Rabenhorst, 1864
- Species Synedra rumpens Kützing, 1844 accepted as Fragilaria capucina subsp. rumpens (Kützing) Lange-Bertalot, 1993
- Species Synedra salina W. Smith, 1853 accepted as Ulnaria salina (W. Sm.) Gogorev, 2018
- Species Synedra salinarum Pantocsek, 1889
- Species Synedra sauvineti Petit, 1888
- Species Synedra saxonica Kützing, 1844
- Species Synedra scalaris Ehrenberg, 1843
- Species Synedra sceptrum
- Species Synedra schaarschmidtii Kanitz
- Species Synedra schroeteri Meister, 1912
- Species Synedra schumannii Rabenhorst, 1864
- Species Synedra scina Hohn & Hellerman, 1966
- Species Synedra scotica
- Species Synedra septata Crouan ex Maze & Schramm, 1880-1887
- Species Synedra serians Rabenhorst, 1848-1860
- Species Synedra sicula Castercane accepted as Nitzschia sicula (Castracane) Hustedt
- Species Synedra sigma Kützing, 1844
- Species Synedra sigmoidea (Nitzsch) Kützing, 1844 accepted as Bacillaria sigmoidea Nitzsch, 1817
- Species Synedra sigmoidea Ehrenberg, 1843
- Species Synedra simbirskiana (Grunow & Pantocsek) Schrader, 1969 accepted as Synedra simbirskiana Grunow, 1884
- Species Synedra simbirskiana Grunow, 1884
- Species Synedra sinica Skvortzov, 2012
- Species Synedra smithii Ralfs, 1861
- Species Synedra smithii O'Meara, 1875
- Species Synedra socia Wallace, 1955
- Species Synedra socialis Rabenhorst, 1853
- Species Synedra spathulata Schimper ex Karsten, 1905
- Species Synedra spathulata O'Meara, 1875
- Species Synedra spathulifera Grunow, 1881
- Species Synedra spectabilis Ehrenberg, 1841
- Species Synedra sphaerophora Meister, 1912
- Species Synedra spinulaeformis W. Smith ex De Toni, 1892
- Species Synedra spinulaeformis W. Smith in Kitton, 1868
- Species Synedra splendens Kützing, 1844 accepted as Ulnaria ulna var. splendens (Kützing) M.Aboal, 2003
- Species Synedra splendens Ehrenberg, 1849
- Species Synedra splendida Ptschelin, 1930
- Species Synedra splendida Ehrenberg, 1870
- Species Synedra stauroneis Ehrenberg, 1856
- Species Synedra stela Hohn & Hellermann, 1963
- Species Synedra strangulata Zanon, 1938
- Species Synedra striata Ehrenberg ex Ralfs in Pritchard, 1861
- Species Synedra striatula
- Species Synedra stricta Karsten, 1905
- Species Synedra striolata Ehrenberg, 1854
- Species Synedra subaequalis Grunow, 1881 accepted as Ulnaria ulna var. subaequalis (Grunow) M.Aboal, 2003
- Species Synedra subarcuata Naegeli ex Kützing, 1849
- Species Synedra subcapitata Wartmann & Schenck, 1864
- Species Synedra subrhombica Nygaard, 1954
- Species Synedra subtilis Kützing, 1844
- Species Synedra subula Sande Lacoste & Suringar, 1860 represented as Ctenophora subula (Sande Lac. & Suringar) D.M.Williams & Van de Vijver, 2023
- Species Synedra subulata Ehrenberg, 1854
- Species Synedra superba Kützing, 1844
- Species Synedra superba sensu Peragallo & Peragallo, 1897-1908
- Species Synedra suriana Pantocsek & Greguss in Greguss, 1913
- Species Synedra szurdokpuespoekiensis Hajós, 1968
- Species Synedra tabulata (C.Agardh) Kützing, 1844 accepted as Tabularia fasciculata (C.Agardh) D.M.Williams & Round, 1986
- Species Synedra taeniata Pantocsek, 1892
- Species Synedra targionii Fiorini-Mazzanti, 1862
- Species Synedra tenella
- Species Synedra tenera W.Smith, 1856 accepted as Fragilaria tenera (W.Smith) Lange-Bertalot, 1980
- Species Synedra tenuis Kützing
- Species Synedra tenuis Ehrenberg, 1854
- Species Synedra tenuissima (Kützing) Kützing, 1844
- Species Synedra tergestina Kützing, 1844
- Species Synedra tergestina (Kützing) Kützing, 1849
- Species Synedra thalassiothrix Cleve, 1873 accepted as Thalassiothrix longissima Cleve & Grunow, 1880
- Species Synedra thalassiotrix Cleve, 1873
- Species Synedra tibialis Tempère & Brun in Brun & Tempère, 1889
- Species Synedra tortuosa D.M.Williams & D.Metzeltin, 2004
- Species Synedra toxoneides Castracane
- Species Synedra transylvanica Pantocsek, 1892
- Species Synedra tropica Grunow, 1862
- Species Synedra truncata Ralfs in Pritchard, 1861
- Species Synedra ulgens Meyer, 1925
- Species Synedra ulna (Nitzsch) Ehrenberg, 1832
- Species Synedra ulna (Kützing) Skabichevskii, 1959
- Species Synedra ulna sensu Hustedt, 1942
- Species Synedra ulna (Kützing) Skabichevskii, 1960
- Species Synedra ulna (Kützing) Skabichevskii, 1959 accepted as Synedra danica Kützing, 1844
- Species Synedra undata Cleve
- Species Synedra undosa Grunow, 1867
- Species Synedra undulans Gregory, 1855
- Species Synedra undulata (J.W.Bailey) Gregory, 1857 accepted as Toxarium undulatum Bailey, 1854
- Species Synedra undulata Schumann, 1862 (1863)
- Species Synedra ungeriana (Grunow) D. M. Williams, 1986
- Species Synedra utermoehlii Hustedt, 1932
- Species Synedra uvella Vereschagin, 1940
- Species Synedra valens Ehrenberg, 1843
- Species Synedra vanheurcki Brun, 1891
- Species Synedra vaucheriae (Kützing) Kützing, 1844 accepted as Fragilaria capucina var. vaucheriae (Kützing) Lange-Bertalot, 1980
- Species Synedra vaucheriae Foged, 1951
- Species Synedra vaucheriae sensu W. Smith, 1853
- Species Synedra ventricosa Rabenhorst, 1853
- Species Synedra vermicularis (Kützing) Kützing, 1844 accepted as Frustulia vermicularis Kützing, 1833
- Species Synedra vertebra Gregory, 1855
- Species Synedra victoriae Woloszynska, 1914
- Species Synedra virginalis Kützing, 1844
- Species Synedra vitrea Kützing, 1844 accepted as Ulnaria amphirhynchus (Ehrenberg) Compère & Bukhtiyarova, 2006
- Species Synedra wartmanni Cramer ex Wartmann & Schenck, 1864
- Species Synedra wigandii Rabenhorst, 1864
- Species Synedra zelleri Rabenhorst, 1864
- Genus Synedrella F.E. Round & N.I. Maidana, 2001 accepted as Pseudostaurosira D.M. Williams & F.E. Round, 1988
- Genus Synedropsis G.R.Hasle, L.K.Medlin & E.E.Syvertsen, 1994 (1)
- Genus Tabularia (F.T. Kutzing) D.M. Williams & F.E. Round, 1986 (18)
- Genus Tabularia F.T. Kutzing, 1844
- Genus Tabulariopsis D.M.Williams, 1988
- Genus Thalassioneis F.E. Round in F.E. Round, R.M. Crawford & D.G. Mann, 1990
- Genus Tibetiella Y.L.Li, D.M.Williams & D.Metzeltin, 2010 (1)
- Genus Trachysphenia P. Petit in Folin & Perrier, 1877 (1)
- Genus Ulnaria (Kützing) P. Compère, 2001 (15)
- Genus Ulnaria F.T. Kutzing, 1844
- Order Licmophorales (49)
- Order Protoraphidales (1)
- Order Rhabdonematales (3)
- Order Rhaphoneidales
- Order Striatellales (15)
- Order Tabellariales (16)
- Order Thalassionematales (10)
- Order Toxariales (1)
- Order Centrales
