DiatomBase
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- Bacillariophyceae (5 957)
- Subclass Bacillariophyceae incertae sedis (189)
- Subclass Bacillariophycidae (4 408)
- Superorder Bacillariophycanae (4 083)
- Order Achnanthales (438)
- Family Achnanthaceae Kützing, 1844 (111)
- Genus Achnantella Gaillon, 1833 accepted as Achnanthes Bory, 1822
- Genus Achnanthes Bory, 1822 (89)
- Species Achnanthes aapajaervensis A.Cleve, 1934
- Species Achnanthes aapajärvensis Cleve-Euler, 1934 accepted as Achnanthes aapajaervensis A.Cleve, 1934
- Species Achnanthes abundans Manguin in Bourrelly & Manguin, 1954 accepted as Psammothidium abundans (Manguin, Bourrelly & Manguin) L.Bukhtiyarova, 1996
- Species Achnanthes acares M.H.Hohn & Hellerman, 1963
- Species Achnanthes acidoclinata Lange-Bert., 1996 accepted as Psammothidium acidoclinatum (Lange-Bertalot) Lange-Bertalot, 1999
- Species Achnanthes acus Simonsen ex F.Hinz et al., 2012
- Species Achnanthes acuta Frenguelli, 1953
- Species Achnanthes adamantiformis (R.E.M.Archibald) R.E.M.Archibald, 1971 accepted as Navigiolum adamantiforme (Archibald) Taylor & Lange-Bertalot
- Species Achnanthes adamsii Cholnoky, 1964
- Species Achnanthes adnata Bory, 1822
- Species Achnanthes affinis Grunow, 1880 accepted as Achnanthidium affine (Grunow) Czarnecki, 1994
- Species Achnanthes africana Woodhead & Tweed, 1958
- Species Achnanthes agardhi (Kütz.) Cleve & J.D.Möller accepted as Achnanthes brevipes var. seriata (Agardh) Cleve, 1895
- Species Achnanthes agglutinans Grunow in Cleve & Möller, 1879
- Species Achnanthes agglutinata Grunow in Cleve & Grunow, 1880
- Species Achnanthes alaskana R.M.Patrick & Freese, 1961 accepted as Achnanthes bioretii Germain, 1957
- Species Achnanthes alpestris (Brun) Lange-Bert. & Metzeltin, 1996 accepted as Eucocconeis alpestris (Brun) Lange-Bertalot, 1999
- Species Achnanthes altaica (V.S.Poretzky) A.Cleve, 1953 accepted as Psammothidium altaicum (Poretzky) L.Bukhtiyarova, 1996
- Species Achnanthes alteragracillima Lange-Bert., 1993 accepted as Achnanthidium gracillimum (Meister) Lange-Bertalot, 2004
- Species Achnanthes ambigua S.J.C.Zimmermann, 1918
- Species Achnanthes americana Cleve, 1893
- Species Achnanthes amoena Hust., 1952 accepted as Karayevia amoena (Hust.) Bukht., 2006
- Species Achnanthes amphicephala Hust., 1939
- Species Achnanthes anastasiae Kaczmarska, 1985 accepted as Achnanthidium anastasiae (Kaczmarska) Chaudev & Gololobova
- Species Achnanthes anceps A.Cleve, 1934
- Species Achnanthes andicola (Cleve) Hust., 1911 accepted as Lemnicola hungarica (Grunow) F.E.Round & P.W.Basson, 1997
- Species Achnanthes angustata Grev., 1859
- Species Achnanthes angustata C.Johnst., 1860 accepted as Gephyria media Arnott, 1860
- Species Achnanthes angustissima Jasn., 1936 accepted as Achnanthes dispar var. angustissima Jasnitsky
- Species Achnanthes annulifera A.Cleve, 1953
- Species Achnanthes antarctica Perag., 1921
- Species Achnanthes antiqua Moiseeva, 1959 †
- Species Achnanthes antiqua ‘M. Peragallo, 1913' according to Hustedt, 1933
- Species Achnanthes antiqua Lauby, 1910 †
- Species Achnanthes antique Lauby accepted as Achnanthes antiqua Lauby, 1910 †
- Species Achnanthes aperta J.R.Carter, 1981 accepted as Skabitschewskia aperta (Carter) Kulikovskiy & Lange-Bertalot, 2015
- Species Achnanthes apiculata (Greville, 1859)
- Species Achnanthes araucaniana Freng., 1934 †
- Species Achnanthes archibaldiana Lange-Bert., 1989 accepted as Rossithidium archibaldianum (Lange-Bertalot) L.N.Bukhtiyarova, 2008
- Species Achnanthes arctica (Cleve) A.Cleve, 1915 accepted as Achnanthes brevipes var. arctica (P. T. Cleve) T. Ko-Bayashi, 1965
- Species Achnanthes arcuata (Lyngb.) Kütz., 1833
- Species Achnanthes arcuata A.Cleve, 1939 accepted as Achnanthes astridii VanLand., 1967
- Species Achnanthes arcus Hust., 1942 accepted as Achnanthidium arcus (Hustedt) Lange-Bertalot, 1999
- Species Achnanthes arenaria Amossé, 1941
- Species Achnanthes arenicola J.W.Bailey, 1851
- Species Achnanthes aretasii Manguin in Bourrelly & Manguin, 1955 accepted as Eucocconeis aretasii (E. Manguin) H. Lange-Bertalot in H. Lange-Bertalot & S. I. Genkal, 1999
- Species Achnanthes arguta Hust.ex Simonsen, 1987
- Species Achnanthes armillaris (O.F.Müller) Guiry, 2019
- Species Achnanthes astridii VanLand., 1967
- Species Achnanthes asymbasia M.H.Hohn, 1966
- Species Achnanthes asymetrica R.M.Patrick, 1936
- Species Achnanthes atacamae Hust., 1927
- Species Achnanthes atalanta J.R.Carter, 1966 accepted as
- Species Achnanthes athenais Pant., 1902 †
- Species Achnanthes atomus Hust., 1937 accepted as Achnanthidium atomus (Hustedt) Monnier, Lange-Bertalot & Ector in Monnier et al., 2004
- Species Achnanthes aubertii Hérib., 1920 †
- Species Achnanthes aueri Krasske, 1949 † accepted as Planothidium aueri (Krasske) H. Lange-Bertalot, 1999
- Species Achnanthes auerii Krasske, 1949 † accepted as Achnanthes aueri Krasske, 1949 †
- Species Achnanthes australis Ehrenb., 1854
- Species Achnanthes austriaca Hust., 1922 accepted as Eucocconeis austriaca (Hustedt) H. Lange-Bertalot apud H. Lange-Bertalot & S.I. Genkal in H. Lange-Bertalot (ed.), 1999
- Species Achnanthes baccata (Leud.-Fortm.) Cleve, 1895
- Species Achnanthes baccillarioides Bory, 1822 accepted as Achnanthes brevipes C.Agardh, 1824
- Species Achnanthes bacescui Bodeanu, 1976
- Species Achnanthes bacillaris Ehrenberg, 1844
- Species Achnanthes bacillum Perag. in Héribaud et al., 1920
- Species Achnanthes bahusiensis (Grunow) Lange-Bert., 1989 accepted as Astartiella bahusiensis (Grunow) Witkowski, Lange-Bertalot & Metzeltin, 1998
- Species Achnanthes baicalansis Skvortsov & Meyer accepted as Achnanthes baicalensis Skvortsov & Meyer, 1928
- Species Achnanthes baicalensis Skvortsov & Meyer, 1928 accepted as Planothidium baicalense (Skvortzow & K.I. Meyer) M.B. Edlund in M.B. Edlund, N. Soninkhishig, R.M. Williams & E.F. Stoermer, 2001
- Species Achnanthes baicaliana Frenguelli, 1953
- Species Achnanthes baldjicki (Brightw.) Grunow † accepted as Rhaphoneis baldjikii (Brightwell) Grunow, 1862
- Species Achnanthes baldjicki sensu Pantocsek, 1892 †
- Species Achnanthes baltalensis H.P.Gandhi, 1998 † accepted as Achnanthes baltalensis H.P.Gandhi ex Karthick, 2020 †
- Species Achnanthes baltalensis H.P.Gandhi ex Karthick, 2020 †
- Species Achnanthes basaltensis Lohman, 1957 †
- Species Achnanthes bavarica Ehrenb., 1853
- Species Achnanthes bengalensis Grunow in Cleve & Grunow, 1880
- Species Achnanthes bergianii A.Cleve, 1953
- Species Achnanthes bergii A.Cleve, 1953
- Species Achnanthes bernieri Manguin ex Kociolek & de Reviers, 1996
- Species Achnanthes biasolettiana Grunow, 1880 accepted as Achnanthidium pyrenaicum (Hustedt) H.Kobayasi, 1997
- Species Achnanthes bicapitata Hustedt, 1952
- Species Achnanthes bicapitellata Cleve-Euler, 1953
- Species Achnanthes biceps Hustedt, 1959
- Species Achnanthes biconfusa VanLandingham, 1967 accepted as Nupela biconfusa (VanLandingham) C.E.Wetzel & Ector, 2018
- Species Achnanthes bigibba Heiden in Heiden & Kolbe, 1928
- Species Achnanthes bijuga Turpin, 1828
- Species Achnanthes bijugata Polenov, 1918
- Species Achnanthes bilunulata Turpin, 1828
- Species Achnanthes binodis Ehrenberg, 1854
- Species Achnanthes bioretii Germain, 1957
- Species Achnanthes biporoma M.H.Hohn & J.Hellerman, 1963 accepted as Planothidium biporomum (M.H.Hohn & Hellerman) Lange-Bertalot, 1999
- Species Achnanthes birugula 'Hohn' VanLandingham, 1967
- Species Achnanthes bistriata Skvortzov, 1937
- Species Achnanthes blancheana R.Maillard ex Lange-Bertalot & A. Steindorf, 1995
- Species Achnanthes bonaeaurae Zanon, 1949
- Species Achnanthes bongrainii (M. Peragallo) Mann, 1937 accepted as Achnanthepyla bongrainii var. bongrainii Perag., 1921
- Species Achnanthes borealis A.Cleve, 1895 accepted as Skabitschewskia borealis (Cleve) Kulikovskey & Lange-Bertalot, 2015
- Species Achnanthes borneolanceolata (ms.) Lange-Bertalot, 1989
- Species Achnanthes bottnica (Cleve) Cleve, 1895 accepted as Achnanthes clevei var. bottnica Cleve, 1891
- Species Achnanthes boudoui Metzeltin & Lange-Bertalot, 1998
- Species Achnanthes bourginii Manguin in Bourrelly & Manguin, 1955
- Species Achnanthes boyei Østrup, 1918 accepted as Planothidium lanceolatum (Brébisson ex Kützing) Bukhtiyarova, 1999
- Species Achnanthes boyeri Mackay in L.W. Bailey, 1924
- Species Achnanthes brachypus Montague
- Species Achnanthes brasiliensis Ehrenberg, 1854
- Species Achnanthes breenii R.E.M. Archibald, 1967
- Species Achnanthes bremeyeri Lange-Bertalot, 1989
- Species Achnanthes brevicostata (Hustedt) Lange-Bertalot & Krammer, 1989 accepted as Cocconeis brevicostata var. brevicostata Hustedt, 1937
- Species Achnanthes brevipes C.Agardh, 1824
- Species Achnanthes brevipes Kützing, 1833
- Species Achnanthes brevis Chernov, 1949
- Species Achnanthes breweri Foged, 1968
- Species Achnanthes brockmannii Hustedt, 1959
- Species Achnanthes broenlundensis Foged, 1955
- Species Achnanthes bruunii Foged, 1957
- Species Achnanthes buccula Cholnoky, 1966
- Species Achnanthes butterfassiana Lange-Bertalot, 1989 accepted as Nupela butterfassiana (Lange-Bertalot) Lange-Bertalot, 1999
- Species Achnanthes calamae Frenguelli, 1930
- Species Achnanthes calcar Cleve, 1891 accepted as Gliwiczia calcar (Cleve) M.Kulikovskiy, Lange-Bertalot & A.Witkowski, 2013
- Species Achnanthes calcaroides Foged, 1971
- Species Achnanthes caledonica Lange-Bertalot, 1994 accepted as Achnanthidium caledonicum (Lange-Bertalot) Lange-Bertalot, 1999
- Species Achnanthes campechiana Hustedt, 1952
- Species Achnanthes campylopus Montagne, 1857
- Species Achnanthes capensis Kützing
- Species Achnanthes capitata Erlandsson, 1930
- Species Achnanthes capitatolineata
- Species Achnanthes capitellata (A. Cleve) Cleve-Euler, 1948 accepted as Navicula capitellata Cleve-Euler, 1943
- Species Achnanthes carissima Lange-Bertalot, 1989
- Species Achnanthes carmichaeli Greville in Hooker, 1833
- Species Achnanthes cassida Carter, 1970
- Species Achnanthes cataractarum (Hustedt) Lange-Bertalot & Krammer, 1989 accepted as Cocconeis cataractarum Hustedt in Schmidt, 1936
- Species Achnanthes catenata Bily & Marvan, 1959
- Species Achnanthes centrafricana Fusey, 1964
- Species Achnanthes ceramii Hendey, 1977
- Species Achnanthes charcotii M. Peragallo, 1921
- Species Achnanthes chilensis Hustedt, 1927 †
- Species Achnanthes chinii Skvortzov, 2012
- Species Achnanthes chlidanos M.H.Hohn & Hellerman, 1963
- Species Achnanthes cincta Andrews, 1971
- Species Achnanthes citrina (Schmidt in Schmidt et al.) M. Peragallo, 1897 accepted as Cocconeis citrina Schmidt in Schmidt et al., 1895
- Species Achnanthes citronella (A.Mann) Hustedt, 1937 accepted as Cocconeis citronella Mann, 1925
- Species Achnanthes clara Cleve-Euler, 1948
- Species Achnanthes clavata Pantocsek, 1902
- Species Achnanthes clevei Grunow, 1880 accepted as Karayevia clevei (Grunow) Round & Bukhtiyarova, 1999
- Variety Achnanthes clevei var. balcanica Hustedt, 1945
- Variety Achnanthes clevei var. bottnica Cleve, 1891
- Variety Achnanthes clevei var. capitata Cleve-Euler, 1953
- Variety Achnanthes clevei var. clevei Grunow, 1880
- Variety Achnanthes clevei var. genuina Cleve-Euler, 1953
- Variety Achnanthes clevei var. nipponica Skvortzow, 1936
- Variety Achnanthes clevei var. pavini Manguin, 1954
- Variety Achnanthes clevei var. rostrata Hustedt, 1930
- Forma Achnanthes clevei f. balcanica Hustedt, 1945
- Forma Achnanthes clevei f. rostrata Hustedt, 1945
- Species Achnanthes coarctata (Brébisson ex W.Smith) Grunow, 1880
- Species Achnanthes cocconeiformis Mann, 1925
- Species Achnanthes cocconeioides Riznyk, 1973
- Species Achnanthes cochinchinensis M. Peragallo, 1897
- Species Achnanthes cogitata Archibald, 1971
- Species Achnanthes cognita Simonsen, 1987
- Species Achnanthes compacta Mann, 1925
- Species Achnanthes conchinchinensis ‘M. Peragallo' VanLandingham, 1967
- Species Achnanthes confusa Manguin
- Species Achnanthes congolensis Hustedt, 1949
- Species Achnanthes conspicua A.Mayer, 1919 accepted as Planothidium conspicuum (A.Mayer) M.Aboal, 2003
- Species Achnanthes conspicuoides Foged, 1981
- Species Achnanthes contracta (Schumann) De Toni, 1891 accepted as Achnanthidium contractum Schumann, 1867
- Species Achnanthes contrarea Lange-Bertalot & A.Steindorf, 1995
- Species Achnanthes controversa Hustedt, 1937
- Species Achnanthes convergens H.Kobayasi ex H.Kobayshi, Nagumo & Mayama, 1986
- Species Achnanthes corrupta Giffen, 1984
- Species Achnanthes costata Greville, 1866
- Species Achnanthes costata Johnston, 1860
- Species Achnanthes cotteriensis Foged, 1978
- Species Achnanthes crassa Hustedt, 1937
- Species Achnanthes crenulata Grunow, 1880
- Species Achnanthes cristata Rabenhorst, 1853
- Species Achnanthes crosbyana Foged, 1979
- Species Achnanthes crucifera Ostrup
- Species Achnanthes cryophila
- Species Achnanthes cryptocephala (Grunow) M.Peragallo, 1897 accepted as Achnanthes minutissima var. cryptocephala Grunow, 1880
- Species Achnanthes cryptocephala ‘Naegeli' Chase, 1907
- Species Achnanthes cucurbita Skvortzow, 1935
- Species Achnanthes cuneata Grunow in Cleve & Grunow as Achnanthes (seriata var.?) cuneata, 1880
- Species Achnanthes curta (A.Cleve) A.Berg ex Cleve-Euler, 1953 accepted as Pinnularia curta var. curta A. Cleve, 1900
- Species Achnanthes curtissima J.R.Carter, 1963 accepted as Psammothidium microscopicum (Cholnoky) S. Blanco, 2016
- Species Achnanthes curvata Leuduger-Fortmorel, 1879
- Species Achnanthes curvirostrum J.Brun, 1895
- Species Achnanthes cyclophora Heiden in Heiden & Kolbe, 1928
- Species Achnanthes dalaica Skvortzov, 2012
- Species Achnanthes danica (Flögel) Grunow in Cleve & Grunow, 1880
- Species Achnanthes danica sensu Pantocsek, 1889
- Species Achnanthes danicoides Giffen, 1975
- Species Achnanthes daonensis Lange-Bertalot, 1989
- Species Achnanthes daui Foged, 1962
- Species Achnanthes debilissima Østrup, 1910
- Species Achnanthes decipiens Reimer, 1966
- Species Achnanthes deflexa C.W.Reimer, 1966
- Species Achnanthes delicatissima Simonsen, 1959
- Species Achnanthes delicatula (Kützing) Grunow in Cleve & Grunow, 1880 accepted as Planothidium delicatulum (Kützing) Round & Bukhtiyarova, 1996
- Species Achnanthes delicatula (Kützing) Brun, 1880 accepted as Achnanthidium delicatulum f. delicatulum Kützing, 1844
- Species Achnanthes delpiroui M. Peragallo in Héribaud et al., 1920
- Species Achnanthes densestriata (Hustedt) Hustedt, 1962 accepted as Navicula densestriata var. densestriata Hustedt, 1922
- Species Achnanthes depressa (Cleve) Hustedt, 1933
- Species Achnanthes desperata Cholnoky, 1959
- Species Achnanthes detha Hohn & Hellerman, 1963
- Species Achnanthes devilensis N.Foged, 1981
- Species Achnanthes didyma Hustedt, 1933
- Species Achnanthes diluviana Hustedt, 1954
- Species Achnanthes dimorpha Turpin, 1828
- Species Achnanthes dimorphostriata H. Kobayashi, 1968
- Species Achnanthes diplopunctata Simonsen, 1959
- Species Achnanthes dispar Cleve, 1891 accepted as Planothidium dispar (Cleve) Witkowski, Lange-Bertalot & Metzeltin, 2000
- Species Achnanthes dispar Mann, 1907
- Species Achnanthes distincta Messikommer, 1954
- Species Achnanthes distorta M. Peragallo, 1921
- Species Achnanthes divergens A.Cleve, 1953
- Species Achnanthes diversa Cleve-Euler, 1953
- Species Achnanthes dornii Lange-Bertalot, 1989
- Species Achnanthes dorogostaiskii Jasnitsky, 1936
- Species Achnanthes drepanocladoides Skvortzov, 2012
- Species Achnanthes dubia Bory, 1822
- Species Achnanthes duthiei Sreenivasa, 1971 †
- Species Achnanthes elata (Leuduger-Fortmorel) Gandhi, 1960
- Species Achnanthes elegans H. Kobayashi, 1965
- Species Achnanthes elliptica (Cleve) Cleve-Euler, 1932 accepted as Planothidium joursacense (Héribaud-Joseph) Lange-Bertalot, 1999
- Species Achnanthes elliptica Skvortzow & Meyer, 1928
- Species Achnanthes elliptica Schumann, 1867
- Species Achnanthes elliptica Kustner, 1914
- Species Achnanthes engelbrechtii Cholnoky, 1955 accepted as Planothidium engelbrechtii (Cholnoky) Round & L.Bukhtiyarova, 1996
- Species Achnanthes entrancensis Foged, 1978
- Species Achnanthes erdmannensis Foged, 1964
- Species Achnanthes eureka Ãlvarez-Blanco & S.Blanco, 2014
- Species Achnanthes eutrophila Lange-Bertalot, 1996
- Species Achnanthes exigua Grunow, 1880
- Species Achnanthes exiguiformis Hustedt, 1948
- Species Achnanthes exiguoides Compère, 1967
- Species Achnanthes exilis Kützing, 1833 accepted as Achnanthidium exile (Kützing) Heiberg, 1863
- Species Achnanthes exilis sensu W. Smith, 1856
- Species Achnanthes exiloides Carter in Carter & Bailey-Watts, 1981
- Species Achnanthes exiloides Cholnoky, 1963
- Species Achnanthes expecta VanLandingham, 1967
- Species Achnanthes expressa J. R. Carter in Hartley, 1986
- Species Achnanthes fasciata Gandhi, 1970
- Species Achnanthes felinophila R.L.Lowe & A.R.Sherwood, 2009
- Species Achnanthes fimbriata (Grunow) R.Ross, 1963 accepted as Schizostauron fimbriatum Grunow, 1867
- Species Achnanthes flahaulti Héribaud, 1903
- Species Achnanthes flathukensis Foged, 1964
- Species Achnanthes flexella (Kützing) Brun, 1880 accepted as Eucocconeis flexella (Kützing) Meister, 1912
- Species Achnanthes flexella (Kützing) Mann, 1937 accepted as Cymbella flexella Kützing, 1844
- Species Achnanthes fluviatilis A.Cleve, 1953
- Species Achnanthes fogedii Håkansson, 1978
- Species Achnanthes follioti Fusey, 1950
- Species Achnanthes fontana Round, 1959
- Species Achnanthes fonticola Hustedt, 1945
- Species Achnanthes fonticolanceolata Lange-Bertalot & Schimanski, 1989
- Species Achnanthes formosa Preobrazhebskaya, 1960
- Species Achnanthes fossilis M. Peragallo in Héribaud et al., 1920
- Species Achnanthes fragilarioides J.B.Petersen, 1924
- Species Achnanthes fragilis Skvortzow, 1938
- Species Achnanthes fraudulenta Cleve-Euler, 1953
- Species Achnanthes fredskildii Foged, 1977
- Species Achnanthes frequentissima Lange-Bertalot, 1989
- Species Achnanthes frigida Hustedt, 1937
- Species Achnanthes frigida Cleve-Euler, 1939
- Species Achnanthes fugei J.R.Carter, 1963
- Species Achnanthes fugeii Carter, 1963
- Species Achnanthes fugiens Cleve-Euler, 1953
- Species Achnanthes fukiensis Skvortzow, 1929
- Species Achnanthes fulla J.R.Carter, 1970
- Species Achnanthes gainii (M. Peragallo) Mann, 1937
- Species Achnanthes gamma (Cleve) Ainosd accepted as Navicula gamma var. gamma Cleve, 1893
- Species Achnanthes genuflexa Kützing, 1844
- Species Achnanthes georgica Reinsch, 1890
- Species Achnanthes germainii Manguin in Bourrelly & Manguin, 1954
- Species Achnanthes gessneri Hustedt, 1953
- Species Achnanthes gibberula Grunow, 1880 accepted as Crenotia gibberula (Grunow) Wojtal
- Species Achnanthes gibbosa Hustedt, 1939
- Species Achnanthes girinensis Skvortzow, 1935
- Species Achnanthes glabrata Grunow
- Species Achnanthes gondwana D. Metzeltin & H. Lange-Bertalot, 2002
- Species Achnanthes gracillima Hustedt, 1927
- Species Achnanthes gracillima (Meister) Mills, 1933
- Species Achnanthes grana Hohn & Hellerman, 1963
- Species Achnanthes gregoriana Greville, 1859
- Species Achnanthes grimmei Krasske, 1925 accepted as Crenotia grimmei (Krasske) Wojtal
- Species Achnanthes grischuna Wuthrich, 1975
- Species Achnanthes groenlandica (Cleve) Grunow, 1880
- Species Achnanthes grubei Simonsen, 1987
- Species Achnanthes grunowii Toyoda & D.M.Williams, 2005
- Species Achnanthes gysingensis (Foged) Lange-Bertalot, 1989 accepted as Navicula gysingensis Foged, 1952
- Species Achnanthes hallandica A.Cleve, 1953
- Species Achnanthes hankensis Skvortzow, 1929
- Species Achnanthes hantzschiana Volkov, 1940
- Species Achnanthes hardingensis Foged, 1981
- Species Achnanthes harrisonii Cholnoky, 1959
- Species Achnanthes harveyi Reimer, 1966
- Species Achnanthes hastata Skvortzow & Meyer, 1928 accepted as Achnanthes subhastata (Skvortzov)
- Species Achnanthes hauckiana Grunow, 1880
- Species Achnanthes hauckii Grunow in Van Heurck, 1880
- Species Achnanthes haynaldii Schaarschmidt, 1881
- Species Achnanthes hedini Hustedt, 1922
- Species Achnanthes hedinii Hustedt accepted as Crenotia hedinii (Hustedt) Rioual, Ector & C.E.Wetzel
- Species Achnanthes heideni
- Species Achnanthes helvetica (Hustedt) Lange-Bertalot, 1989 accepted as Achnanthes austriaca var. helvetica Hust., 1933
- Species Achnanthes herteri Frenguelli, 1933
- Species Achnanthes heteromorpha Grunow, 1880 accepted as Planothidium heteromorphum (Grunow) Lange-Bertalot, 1999
- Species Achnanthes heteropsis Grunow ex Cleve & Möller, 1878
- Species Achnanthes heterostriata Hustedt, 1952
- Species Achnanthes heterostriatoides Hohn in Patrick et al., 1966
- Species Achnanthes heterovalvata (Krasske) Frenguelli, 1942 accepted as Achnanthes exigua f. heterovalvata Krasske, 1923
- Species Achnanthes hettensis Cleve-Euler, 1953
- Species Achnanthes hexagona Cleve & Brun in Brun, 1891
- Species Achnanthes hilliardii Manguin, 1961
- Species Achnanthes himalayensis Jao & Zhu in Jao, Zhu & Lee, 1974
- Species Achnanthes hintzii Lange-Bertalot & Krammer, 1989
- Species Achnanthes hirta Carter, 1970
- Species Achnanthes hoermannii Gutwinski, 1899
- Species Achnanthes holmquistii Foged, 1968
- Species Achnanthes holsatica Hustedt, 1936
- Species Achnanthes holstii Cleve, 1882 accepted as Planothidium holstii (Cleve) Lange-Bertalot, 1999
- Species Achnanthes hormanii Gutwinski, 1899
- Species Achnanthes hudsonis Grunow, 1880
- Species Achnanthes hungarica (Grunow) Grunow, 1880 accepted as Lemnicola hungarica (Grunow) F.E.Round & P.W.Basson, 1997
- Species Achnanthes hustedtii (Krasske) Reimer, 1966 accepted as Cocconeis hustedtii Krasske, 1923
- Species Achnanthes hustedtii Bily & Marvan, 1959
- Species Achnanthes hyperborea (Grunow) Grunow, 1884
- Species Achnanthes hyperboreoides A.Witkowski, D.Metzeltin & Lange-Bertalot, 1996
- Species Achnanthes ignota Hustedt, 1958
- Species Achnanthes Imanishii Hirano, 1963
- Species Achnanthes imperfecta Schimanski, 1978
- Species Achnanthes impexa Lange-Bertalot, 1989
- Species Achnanthes impexiformis Lange-Bertalot, 1989
- Species Achnanthes inaequalis Ehrenberg, 1838
- Species Achnanthes incognita Krasske, 1939 accepted as Psammothidium incognitum (Krasske) Van de Vijver, 2002
- Species Achnanthes incrassata Ehrenberg, 1854
- Species Achnanthes indica Brun, 1893
- Species Achnanthes indicatrix Lange-Bertalot & A.Steindorf, 1998
- Species Achnanthes indicta Cleve-Euler, 1953
- Species Achnanthes inflata (Kützing) Grunow, 1867
- Species Achnanthes inflatagrandis D. Metzeltin, H. Lange-Bertalot & F. García-Rodríguez, 2005
- Species Achnanthes ingratiformis Lange Bertalot, 1989
- Species Achnanthes inopinata Cleve
- Species Achnanthes intermedia Kützing, 1833
- Species Achnanthes interrupta J.R.Carter, 1961
- Species Achnanthes investiens Carter, 1966
- Species Achnanthes iranensis Moghadam, 1976
- Species Achnanthes islandica Østrup, 1918
- Species Achnanthes iversenii Foged, 1977
- Species Achnanthes jackii (Rabenhorst) Tempère & Peragallo, 1909 accepted as Achnanthidium jackii Rabenhorst, 1861
- Species Achnanthes jacksonii Woodhead & Tweed, 1960
- Species Achnanthes jacobii Manguin, 1949
- Species Achnanthes jakovljevici Hustedt, 1945
- Species Achnanthes jamaicense Podzorski, 1985
- Species Achnanthes jamalinensis Grunow in Cleve & Grunow, 1880
- Species Achnanthes jan-marcinii Witkowski, Metzeltin & Lange-Bertalot, 1996
- Species Achnanthes japonica Kobayasi, 1965
- Species Achnanthes japonica Kobayasi ex Kobayasi, Nagumo & Mayama, 1986
- Species Achnanthes javanica Grunow in Cleve & Möller, 1878
- Species Achnanthes javanica Ehrenberg, 1854
- Species Achnanthes jeniseyensis Skvortzow, 1971
- Species Achnanthes jentzschi (Grunow) P.Schulz, 1926 accepted as Navicula jentzschii f. jentzschii Grunow, 1882
- Species Achnanthes jilinensis Huang in Huang et al., 1983 †
- Species Achnanthes jogensis Gandhi, 1966
- Species Achnanthes johncarteri Lange-Bertalot & Krammer, 1989
- Species Achnanthes joursacense Héribaud-Joseph, 1903
- Species Achnanthes juriljii VanLandingham, 1967
- Species Achnanthes kamczatica E.G.Lupikina, 1965 †
- Species Achnanthes kansouensis Skvortzow, 1935
- Species Achnanthes karelica Mölder, 1951
- Species Achnanthes karelica Cleve-Euler, 1953
- Species Achnanthes kenaiensis Stone in McLaughlin & Stone, 1986
- Species Achnanthes kenyae Cholnoky, 1960
- Species Achnanthes kerguelenensis Castracane, 1886
- Species Achnanthes Kertschiana Pantocsek, 1902
- Species Achnanthes kisselevi Vladimirova, 1947
- Species Achnanthes kizaki Skvortzow, 1936
- Species Achnanthes koenigii Simonsen, 1959
- Species Achnanthes koghisensis G.Moser, Lange-Bertalot & D.Metzeltin, 1998
- Species Achnanthes kolbei Hustedt, 1930 accepted as Karayevia kolbei (Hudtedt) Bukhtiyarova, 1999
- Species Achnanthes koreana Skvortzow, 1936
- Species Achnanthes koshovii Jasnitsky, 1936
- Species Achnanthes kraeuselii Cholnoky, 1954 accepted as Achnanthes subhudsonis var. kraeuselii (Cholnoky) Cholnoky, 1956
- Species Achnanthes kranzii Lange-Bertalot, 1989
- Species Achnanthes krasskei Kobayasi & Sawatari, 1986
- Species Achnanthes krejcii Hustedt in Schmidt et al., 1937 accepted as Platessa krejcii (Hustedt, 1937) C.E.Wetzel, Tudesque & Le Cohu, 2016
- Species Achnanthes krejcii Hustedt, 1950
- Species Achnanthes kriegeri Krasske, 1943 accepted as Rossithidium kriegeri (Krasske) Bahls, 2019
- Species Achnanthes kryophila J.B.Petersen, 1924 accepted as Achnanthes chlidanos M.H.Hohn & Hellerman, 1963
- Species Achnanthes kryophiloides Hohn, 1966 accepted as Achnanthidium peruvianum E.Morales & L.Ector, 2011
- Species Achnanthes kryophiloides Foged, 1964
- Species Achnanthes kuelbsii Lange-Bertalot, 1989
- Species Achnanthes kuolensis Cleve-Euler, 1934
- Species Achnanthes kuwaitensis Hendey, 1958
- Species Achnanthes lacunarum Hustedt, 1930
- Species Achnanthes lacunicola Patrick & Freese, 1961
- Species Achnanthes lacus-baicali Skvortzov, 1937 accepted as Achnanthes lakus-baikali Skvortzow, 1937
- Species Achnanthes lacus-karluki E.Manguin ex Kociolek & Reviers, 1996
- Species Achnanthes lacus-vulcani Lange-Bertalot & Krammer, 1989
- Species Achnanthes laevis Østrup, 1910
- Species Achnanthes lakus-baikali Skvortzow, 1937
- Species Achnanthes lanceolata (Brébisson ex Kützing) Grunow, 1880 accepted as Planothidium lanceolatum (Brébisson ex Kützing) Bukhtiyarova, 1999
- Species Achnanthes lanceolata (Patrick) Lange-Bertalot, 1993 accepted as Achnanthes lanceolata var. apiculata R.M.Patrick, 1945
- Species Achnanthes lanceolata (Hohn & Hellerman) Lange-Bertalot, 1993 accepted as Achnanthes biporoma M.H.Hohn & J.Hellerman, 1963
- Species Achnanthes lanceolata Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991
- Species Achnanthes lanceolata (Sovereign) Lange-Bertalot, 1993 accepted as Achnanthes lanceolatoides H.E.Sovereign, 1958
- Species Achnanthes lanceolata (Hustedt) Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991 accepted as Achnanthes lanceolata var. robusta Hustedt, 1937
- Species Achnanthes lanceolata (Østrup) Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991 accepted as Achnanthes rostrata Oestrup, 1902
- Species Achnanthes lanceolata (Hustedt) Lange-Bertalot, 1993 accepted as Achnanthes lanceolata var. robusta Hustedt, 1937
- Species Achnanthes lanceolata (Grunow) Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991 accepted as Achnanthes lanceolata var. dubia sensu van Heurck
- Species Achnanthes lanceolata Lange-Bertalot, 1993
- Species Achnanthes lanceolata (Sovereign) Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991 accepted as Achnanthes lanceolatoides H.E.Sovereign, 1958
- Species Achnanthes lanceolata (Østrup) Lange-Bertalot, 1993 accepted as Achnanthes rostrata Oestrup, 1902
- Species Achnanthes lanceolata Skabichevskii, 1987
- Species Achnanthes lanceolata (Patrick) Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991 accepted as Achnanthes lanceolata var. apiculata R.M.Patrick, 1945
- Species Achnanthes lanceolata (Hohn & Hellerman) Lange-Bertalot in Krammer & Lange-Bertalot in H. Ettl et al., 1991 accepted as Achnanthes biporoma M.H.Hohn & J.Hellerman, 1963
- Species Achnanthes lanceolatoides H.E.Sovereign, 1958
- Species Achnanthes lancettula Østrup in Héribaud et al., 1920
- Species Achnanthes lancettula Cleve-Euler, 1953
- Species Achnanthes lapeyrerei Tempère & M. Peragallo in Tempère & Peragallo, 1908
- Species Achnanthes lapidosa Krasske, 1929 accepted as Nupela lapidosa (Krasske) Lange-Bertalot, 1999
- Species Achnanthes laportei Manguin, 1954
- Species Achnanthes lapponica (Hustedt) Hustedt, 1933 accepted as Eucocconeis quadratarea (Østrup) Lange-Bertalot, 1999
- Species Achnanthes larsenii Foged, 1968
- Species Achnanthes lata Hustedt, 1942
- Species Achnanthes laterostrata Hustedt, 1933
- Species Achnanthes latestriata Riznyk, 1973
- Species Achnanthes latissima Cleve-Euler, 1915
- Species Achnanthes lauenburgiana Hustedt, 1950
- Species Achnanthes lecohui Coste & Ricard, 1982
- Species Achnanthes leibleinii Agardh, 1832
- Species Achnanthes lemmermannii Hustedt, 1933
- Species Achnanthes leonardii Witkowski & Lange-Bertalot, 2000
- Species Achnanthes leontopithecus-rosalia J.C.F. da Costa, 1995
- Species Achnanthes lesothensis Schoeman, 1973
- Species Achnanthes leudugeri Tempère & Brun in Brun & Tempère, 1889
- Species Achnanthes levanderi Hustedt, 1933 accepted as Psammothidium levanderi (Hustedt) L.Bukhtiyarova & Round, 1996
- Species Achnanthes leveillei Héribaud in Héribaud et al., 1920
- Species Achnanthes lewisiana R.M.Patrick, 1945
- Species Achnanthes ligeriana Héribaud, 1903
- Species Achnanthes lilljeborgei Grunow, 1881 accepted as Planothidium lilljeborgei (Grunow) Witkowski
- Species Achnanthes lilljeborgii Grunow, 1881
- Species Achnanthes lineare W.Smith, 1855 accepted as Achnanthes linearis (W.Smith) Grunow, 1880
- Species Achnanthes lineariformis Lange-Bertalot, 1993
- Species Achnanthes lineariformis H. Kobayashi, 1965
- Species Achnanthes lineariformis H. Kobayashi, 1964
- Species Achnanthes linearioides Lange-Bertalot in Lange-Bertalot & Moser, 1994
- Species Achnanthes linearis (W.Smith) Grunow, 1880 accepted as Achnanthidium lineare W.Smith, 1855
- Species Achnanthes linkei Hustedt, 1939 accepted as Planothidium linkei (Hustedt) Lange-Bertalot, 1999
- Species Achnanthes lintonensis J.R.Carter, 1961
- Species Achnanthes lobata (Schwartz ex Rabenhorst) Hustedt, 1952 accepted as Navicula lobata Schwartz in Rabenhorst, 1877
- Species Achnanthes loczyi Pantocsek, 1889
- Species Achnanthes longboardia A.R.Sherwood & R.L.Lowe, 2009
- Species Achnanthes longipes C.Agardh, 1824
- Species Achnanthes looseri Frenguelli, 1930 accepted as Planothidium looseri (Frenguelli) Rivero & Cruces, 2009
- Species Achnanthes lorenziana Grunow ex A.Schmidt, 1895
- Species Achnanthes lucana Carter, 1970
- Species Achnanthes lutheri Hustedt, 1933
- Species Achnanthes lyrata Proschkina-Lavrenko, 1961
- Species Achnanthes lyroides König, 1959
- Species Achnanthes maceneryae Reimer & Lee, 1988
- Species Achnanthes macquariensis Foged, 1978
- Species Achnanthes macropus Kützing in lit. in Kützing, 1844
- Species Achnanthes maculata Hustedt, 1937
- Species Achnanthes maewensis Foged, 1972
- Species Achnanthes magnifica Hustedt, 1952
- Species Achnanthes mamchyi Skvortzow, 1975
- Species Achnanthes mammalis (Castracane) Cleve
- Species Achnanthes manguinii Hustedt
- Species Achnanthes manifera Brun, 1895
- Species Achnanthes mannii ‘Pantocsek' VanLandingham, 1979
- Species Achnanthes mansiensis Foged, 1966
- Species Achnanthes maolanensis P. Yu, J.P. Kociolek & Q-M. You in You et al., 2019
- Species Achnanthes maranda N.Woodhead & R.D.Tweed, 1958
- Species Achnanthes margaritaceum Cleve, 1893
- Species Achnanthes margaritarum Cleve, 1893
- Species Achnanthes marginalis Hendey, 1958
- Species Achnanthes marginestriata Simonsen, 1959
- Species Achnanthes marginulata Grunow, 1880
- Species Achnanthes marina Hustedt, 1937
- Species Achnanthes marraitensis Foged, 1958
- Species Achnanthes martyi Héribaud in Héribaud et al., 1920
- Species Achnanthes mauiensis R.L.Lowe & A.R.Sherwood, 2009
- Species Achnanthes maxima A.Cleve, 1953 accepted as Achnanthidium maximum Cleve-Euler, 1895
- Species Achnanthes medioconvexa Zhu & Chen, 1996
- Species Achnanthes meisteri Hustedt ex R.Simonsen, 1987
- Species Achnanthes mercuryi Witkowski, Metzeltin & Lange-Bertalot in Metzeltin & Witkowski, 1996
- Species Achnanthes mesoconstricta Zhu & Chen, 1996
- Species Achnanthes mesogongyla Grunow in Cleve & Grunow, 1880
- Species Achnanthes metaffinis Lange-Bertalot & A.Steindorf, 1995
- Species Achnanthes metakryophila Lange-Bertalot & Schmidt, 1990
- Species Achnanthes meyeri Skvortzow, 1937
- Species Achnanthes mica Hohn in Patrick et al., 1966
- Species Achnanthes microcephala (Kützing) Grunow, 1880 accepted as Achnanthidium microcephalum Kützing, 1844
- Species Achnanthes microcephala (Kützing) Cleve, 1895 accepted as Achnanthidium microcephalum Kützing, 1844
- Species Achnanthes microscopica (Cholnoky) Lange-Bertalot & Krammer, 1989 accepted as Cocconeis microscopica Cholnoky, 1959
- Species Achnanthes minima J.R.Carter, 1961
- Species Achnanthes minuscula Hustedt, 1945
- Species Achnanthes minuta (Cleve) Cleve-Euler, 1953 accepted as Achnanthidium minutum Cleve, 1891
- Species Achnanthes minuta (Cleve) Patrick & Freese, 1961 accepted as Achnanthidium minutum Cleve, 1891
- Species Achnanthes minutissima Kützing, 1833
- Species Achnanthes miocaenica Moiseeva, 1959
- Species Achnanthes miota Carter & Denny, 1982
- Species Achnanthes mirabilis Proschkina-Lavrenko, 1955
- Species Achnanthes misionera Frenguelli, 1953
- Species Achnanthes modesta Manguin in Bourrelly & Manguin, 1954 accepted as Achnanthidium modestiforme (Lange-Bert.) Van de Vijver in Van de Vijver et al., 2002
- Species Achnanthes modesta Manguin, 1952
- Species Achnanthes modestiformis Lange-Bert. in Lange-Bertalot & Krammer, 1989 accepted as Achnanthidium modestiforme (Lange-Bert.) Van de Vijver in Van de Vijver et al., 2002
- Species Achnanthes modica Hustedt, 1952
- Species Achnanthes mollis Krasske, 1939
- Species Achnanthes monela Hohn & Hellerman, 1963
- Species Achnanthes montana Krasske, 1929 accepted as Psammothidium montanum (Krasske) Mayuma, 2002
- Species Achnanthes montdorensis Manguin, 1954
- Species Achnanthes muelleri Carlson, 1913
- Species Achnanthes muelleri ‘Pantocsek' VanLandingham, 1979
- Species Achnanthes multiarticulata Agardh, 1832
- Species Achnanthes muscorum M.Peragallo
- Species Achnanthes nagpurensis Sarode & Kamat, 1984
- Species Achnanthes namae Giffen, 1984
- Species Achnanthes nana Meister, 1934
- Species Achnanthes nathorsti Brun, 1901
- Species Achnanthes natrata Carter, 1966
- Species Achnanthes navalis Giffen, 1976
- Species Achnanthes naviformis Van de Vijver & Beyens in Van de Vijver et al., 2002
- Species Achnanthes neglecta Chi & Ruowen
- Species Achnanthes neocaledonica Manguin, 1962
- Species Achnanthes neocaledonica Manguin ex Lange-Bertalot & Steindorf in Moser, Steindorf & Lange-Bertalot, 1995
- Species Achnanthes neocaledonica Manguin ex Kociolek & Reviers, 1996
- Species Achnanthes neohustedtii VanLandingham, 1979
- Species Achnanthes neokisselevii VanLandingham, 1969
- Species Achnanthes neoskvortzowii Simonsen, 1987
- Species Achnanthes nikiskii Stone in McLaughlin & Stone, 1986
- Species Achnanthes ninckei P.Guermeur & E.Manguin, 1953
- Species Achnanthes nitida Cleve-Euler, 1939
- Species Achnanthes nitidiformis Lange-Bertalot, 1989
- Species Achnanthes nivellis Fusey, 1953
- Species Achnanthes nobile Schulz, 1926
- Species Achnanthes nodeana Skvortzow in Skvortzow & Noda, 1971
- Species Achnanthes nodosa Cleve, 1900
- Species Achnanthes nollii O. & W.Bock, 1953
- Species Achnanthes normanii
- Species Achnanthes norvegica Hustedt accepted as Achnanthes montana var. norvegica Hustedt, 1931
- Species Achnanthes obesa (Greville, 1865)
- Species Achnanthes obliqua (Gregory) Hustedt, 1924 accepted as Gololobovia obliqua (W.Gregory) Kulikovskiy, Glushchenko & Kociolek in Kulikovskiy et al., 2020
- Species Achnanthes obliqua Turpin, 1828
- Species Achnanthes oblonga E.Manguin ex Kociolek & Reviers, 1996
- Species Achnanthes oblongella Østrup, 1902
- Species Achnanthes obscura (Krasske) Lange-Bertalot & M.Willmann, 1996
- Species Achnanthes obtusa Ehrenberg in Ralfs in Pritchard, 1861
- Species Achnanthes obtusa (Schumann) De Toni, 1891 accepted as Achnanthidium obtusum Schumann, 1867
- Species Achnanthes occulta Kalbe, 1963
- Species Achnanthes ocellata Manguin, 1952
- Species Achnanthes octalterna Turpin, 1828
- Species Achnanthes oculata Hustedt
- Species Achnanthes oerensis Cleve-Euler, 1953
- Species Achnanthes oestrupii (Cleve-Euler) Hustedt, 1930
- Species Achnanthes okamurae Skvortzow, 1937
- Species Achnanthes okunoi (Hustedt) Simonsen, 1988 accepted as Navicula okunoi Hustedt, 1966
- Species Achnanthes onegensis (Wislouch & Kolbe) Jouse, 1939 accepted as Psammothidium obliquum (W. Gregory, 1856) Potapova, 2018
- Species Achnanthes oregonensis Riznyk, 1973
- Species Achnanthes orellana Hohn in Patrick et al., 1966
- Species Achnanthes orientalis Hustedt, 1933
- Species Achnanthes orientalis Meister, 1937
- Species Achnanthes orientalis Petit, 1904
- Species Achnanthes ostenii J.Frenguelli, 1933
- Species Achnanthes ostrupii
- Species Achnanthes pachypus Montagne, 1839
- Species Achnanthes pachypus Montagne, 1838
- Species Achnanthes pagesi M. Peragallo in Héribaud et al., 1920
- Species Achnanthes paIustris P.Fusey
- Species Achnanthes palustris
- Species Achnanthes pamirensis Hustedt, 1922
- Species Achnanthes pantocseki Hajós, 1968
- Species Achnanthes papillosa Cleve-Euler, 1953
- Species Achnanthes paradoxa Ehrenberg, 1845
- Species Achnanthes parallela Carter, 1963 accepted as Achnanthes petersenii Hustedt, 1937
- Species Achnanthes parallela Castracane, 1886
- Species Achnanthes parexigua D.Metzeltin & Lange-Bertalot, 1998
- Species Achnanthes parvula Kützing, 1844
- Species Achnanthes parvula Kützing, 1836
- Species Achnanthes pelta Hohn & Hellerman, 1966
- Species Achnanthes pennaeformis Greville, 1866
- Species Achnanthes pennata Greville in Cleve, 1883
- Species Achnanthes peragalli Brun & Héribaud-Joseph, 1893 accepted as Skabitschewskia peragalli (Brun & Heribaud) Kulikovskiy & Lange-Bertalot, 2015
- Species Achnanthes peragalloi Brun & Héribaud-Joseph, 1893
- Species Achnanthes perfida J.R.Carter, 1963
- Species Achnanthes pericava J.R.Carter, 1966
- Species Achnanthes peridotitica Moser, Lange-Bertalot & Metzeltin, 1998
- Species Achnanthes perminuta Østrup, 1913
- Species Achnanthes perpusilla (Østrup) Lange-Bertalot in Lange-Bertalot & Metzeltin, 1996 accepted as Psammothidium perpusillum (Østrup) Lange-Bertalot, 1999
- Species Achnanthes perpusilla (Østrup) Lange-Bertalot in Lange-Bertalot & Moser, 1994
- Species Achnanthes perturba VanLandingham, 1967
- Species Achnanthes petersenii Hustedt, 1937
- Species Achnanthes petiti Aleem, 1954
- Species Achnanthes philippinica Skvortzow, 1937
- Species Achnanthes piafica Carter & Denny, 1982
- Species Achnanthes pictii J.R.Carter, 1963
- Species Achnanthes pinnata Hustedt, 1922 accepted as Achnanthes conspicua A.Mayer, 1919
- Species Achnanthes pinnularia (Tempère & Brun) Kanaya, 1963 accepted as Rhaphoneis pinnularia Tempère & Brun in Brun & Tempère, 1889
- Species Achnanthes pirogueana R.Maillard, 1978
- Species Achnanthes pitoti
- Species Achnanthes placentuloides (Guslakov) Witkowski & Lange-Bertalot, 2000 accepted as Cocconeis placentuloides Guslakov, 1992
- Species Achnanthes plana J.R.Carter, 1963
- Species Achnanthes pletei
- Species Achnanthes plitvicensis Hustedt, 1945
- Species Achnanthes ploenensis Hustedt, 1930 represented as Karayevia ploenensis (Hustedt) Bukhtiyarova, 1999
- Species Achnanthes ploenensis sensu Poretzky, 1933
- Species Achnanthes polaris Oestrup, 1895
- Species Achnanthes polynesica H. Lange-Bertalot & M. Werum in Werum & Lange-Bertalot, 2004
- Species Achnanthes poretzkii Jasnitsky accepted as Skabitschewskia poretzkii (Jasnitsky) Kulikovskiy & Lange-Bertalot, 2015
- Species Achnanthes portae Cholnoky, 1959
- Species Achnanthes praecipua E.Reichardt, 1988 accepted as Nupela praecipua (Reichardt) Reichardt in U. Rumrich, H. Lange-Bertalot & M. Rumrich, 2000
- Species Achnanthes prava Sovereign, 1963
- Species Achnanthes procera Hustedt, 1945
- Species Achnanthes profunda Skvortzov, 1937
- Species Achnanthes prominula Z.Levkov & S.Tofilovska, 2014
- Species Achnanthes promunturii Giffen, 1970
- Species Achnanthes pseudincognita Cleve-Euler, 1953
- Species Achnanthes pseudoaffinis Maillard, 1978
- Species Achnanthes pseudo-antiqua M. Peragallo in Héribaud et al., 1920
- Species Achnanthes pseudobiasolletiana H.P.Gandhi, 1961
- Species Achnanthes pseudobiceps H.Håkansson, 1974
- Species Achnanthes pseudobliqua Simonsen, 1960
- Species Achnanthes pseudobrevipes Aleem, 1950
- Species Achnanthes pseudocoarctata Z.Levkov & S.Tofilovska, 2014
- Species Achnanthes pseudoconica Foged accepted as Achnanthes pseudoconspicua Foged, 1972
- Species Achnanthes pseudoconspicua Foged, 1972
- Species Achnanthes pseudoexigua Loseva, 1982
- Species Achnanthes pseudoexigua Skvortzov, 2012
- Species Achnanthes pseudogrimmei Cholnoky, 1970
- Species Achnanthes pseudogroenlandica Hendey, 1964
- Species Achnanthes pseudohexagona Hustedt, 1952
- Species Achnanthes pseudohungarica Cholnoky-Pfannkuche, 1966
- Species Achnanthes pseudohustedtii Kobayasi in Ando, Haraguchi & Kobayasi, 1971
- Species Achnanthes pseudoinflata M. Rybak, Peszek, Skoczylas, Ector & C.E. Wetzel in Rybak et al., 2020
- Species Achnanthes pseudolanceolata Hustedt, 1952
- Species Achnanthes pseudolanceolata Manguin, 1962
- Species Achnanthes pseudolinearis Hustedt, 1942
- Species Achnanthes pseudolongipes K.Toyoda & T.Nagumo, 2010
- Species Achnanthes pseudo-obliqua Kobayasi in Ando, Haraguchi & Kobayasi, 1971
- Species Achnanthes pseudopinnata Foged, 1972
- Species Achnanthes pseudopunctulata Simonsen, 1959
- Species Achnanthes pseudoscutiformis Loseva, 1982
- Species Achnanthes pseudoseminulum Cleve-Euler, 1934
- Species Achnanthes pseudosolea Simonsen, 1959
- Species Achnanthes pseudosuchlandtii Manguin, 1961
- Species Achnanthes pseudoswazi J.R.Carter, 1963
- Species Achnanthes pseudotanensis A.Cleve-Euler, 1953
- Species Achnanthes pulchella Heiden in Heiden & Kolbe, 1928
- Species Achnanthes pulcherrima (Hustedt) Metzeltin & Lange-Bertalot, 1998
- Species Achnanthes pulviscula Cholnoky, 1960
- Species Achnanthes punctata Round, 1959
- Species Achnanthes punctifera Hustedt, 1955
- Species Achnanthes punctulata Simonsen, 1959
- Species Achnanthes pusilla Grunow in Cleve & Grunow, 1880
- Species Achnanthes pusilla Woodhead & Tweed, 1960
- Species Achnanthes pusilla Grunow in Cleve & Möller, 1879
- Species Achnanthes pusilla Grunow in Van Heurck, 1880
- Species Achnanthes pyrenaica Hustedt, 1939 accepted as Achnanthidium pyrenaicum (Hustedt) H.Kobayasi, 1997
- Species Achnanthes pyropa Carter, 1970
- Species Achnanthes quadralterna Turpin, 1828
- Species Achnanthes quadratarea (Østrup) M.Möller ex Foged, 1974 accepted as Cocconeis quadratarea Østrup, 1910
- Species Achnanthes quadricauda Turpin, 1828
- Species Achnanthes quadrijuga Turpin, 1828
- Species Achnanthes quadripunctata D.R. Oppenheim, 1995
- Species Achnanthes qualternus Turpin in Mém. Mus. according to Mills, 1828
- Species Achnanthes radiata Du & Cheng, 1984
- Species Achnanthes radiata Skvortzov, 2012
- Species Achnanthes radiatus Hohn & Hellerman, 1966
- Species Achnanthes radiosa Hustedt in Schmidt et al., 1936
- Species Achnanthes radiosa Hustedt ex Simonsen, 1987
- Species Achnanthes ramosa P.L.Crouan & H.M.Crouan
- Species Achnanthes ranomafanensis Manguin, 1952
- Species Achnanthes rara Jurilj, 1957
- Species Achnanthes rarissima Skvortzov, 2012
- Species Achnanthes rautenbachiae Cholnoky, 1957
- Species Achnanthes recava Hohn & Hellerman, 1966
- Species Achnanthes rechtensis Leclercq, 1983
- Species Achnanthes recurva Ehrenberg, 1858
- Species Achnanthes recurvata Hustedt, 1937
- Species Achnanthes reichardtiana (Grunow) Hustedt, 1933 accepted as Schizostauron reichardtianum Grunow, 1867
- Species Achnanthes reichardtiana (Grunow) Cleve, 1902 accepted as Schizostauron reichardtianum Grunow, 1867
- Species Achnanthes reidensis Foged, 1978
- Species Achnanthes reimeri Camburn in Camburn, Lowe & Stoneburner, 1978
- Species Achnanthes renei Lange-Bertalot & Schmidt, 1990
- Species Achnanthes repanda Tsumura & Iwahashi, 1955
- Species Achnanthes repestoides ‘Hohn' VanLandingham, 1967
- Species Achnanthes restricta Cleve-Euler, 1953
- Species Achnanthes reversa Lange-Bertalot, 1989
- Species Achnanthes rhombica Oestrup, 1910
- Species Achnanthes rhombica Skabichevskii, 1987
- Species Achnanthes rhombica Voigt in Meister, 1935
- Species Achnanthes rhomboides Ehrenberg, 1843
- Species Achnanthes rhynchocephala Cleve-Euler, 1915
- Species Achnanthes ricula Hohn & Hellerman, 1963 accepted as Navigiolum ricula (M.H.Hohn & Hellerman) C.E.Wetzel & Ector, 2018
- Species Achnanthes rivularia Frenguelli, 1925 accepted as Achnanthes hungarica var. rivularia (Frenguelli) Frenguelli, 1933
- Species Achnanthes robusta Rivera, 1973
- Species Achnanthes rollae Suxena & Venkateswarlu, 1968
- Species Achnanthes rosenstockii Lange-Bertalot, 1989
- Species Achnanthes rossii Hustedt, 1954
- Species Achnanthes rostellata A.Cleve, 1934
- Species Achnanthes rostrata Oestrup, 1902
- Species Achnanthes rupestoides Hohn, 1961
- Species Achnanthes rupestris Krasske, 1932 accepted as Platessa rupestris (Krasske) Lange-Bertalot, 2004
- Species Achnanthes saccula J.R.Carter, 1981
- Species Achnanthes sacculus Carter in Carter & Bailey-Watts, 1981 accepted as Psammothidium sacculum (J.R.Carter) L.Bukhtiyarova, 1996
- Species Achnanthes saeptata
- Species Achnanthes salina (Kützing) Kützing, 1844 accepted as Fragilaria salina Kützing, 1833
- Species Achnanthes salvadoriana Hustedt, 1953 accepted as Planothidium salvadorianum (Hustedt) Lange-Bertalot, 1999
- Species Achnanthes sancti-paulii (Heiden in Heiden & Kolbe) Kobayasi & Sawatari, 1986 accepted as Cocconeis sancti-pauli Heiden in Heiden & Kolbe, 1928
- Species Achnanthes sapinii-jaloustrei Manguin, 1957
- Species Achnanthes saxatilis Bock, 1970
- Species Achnanthes saxonica Krasske ex Hustedt, 1933
- Species Achnanthes saxophila Lange-Bertalot & Krammer
- Species Achnanthes schmidtiana Krenner, 1926
- Species Achnanthes schmidtii Heiden in Heiden & Kolbe, 1928
- Species Achnanthes schoemaniana Giffen, 1984
- Species Achnanthes schultzii Cholnoky, 1933
- Species Achnanthes schulzi Brockmann, 1954
- Species Achnanthes Schulzii Cleve-Euler, 1932
- Species Achnanthes schwabei Krasske, 1939 accepted as Planothidium schwabei (Krasske) H. Lange-Bertalot in U. Rumrich, H. Lange-Bertalot & M. Rumrich, 2000
- Species Achnanthes scotica R.J.Flower & V.J.Jones, 1989
- Species Achnanthes scotica Lange-Bertalot, 1993
- Species Achnanthes scutiformis Moiseeva, 1960
- Species Achnanthes secretitaeniata Toyoda, Tanaka & Williams, 2009
- Species Achnanthes semen Ehrenberg, 1854
- Species Achnanthes semiaperta Hustedt, 1945
- Species Achnanthes semifasciata (Østrup) M. Møller in Foged, 1974 accepted as Navicula semifasciata Østrup, 1918
- Species Achnanthes separata Hustedt ex Simonsen, 1987
- Species Achnanthes separata Hustedt in Schmidt et al., 1958
- Species Achnanthes septata Cleve-Euler
- Species Achnanthes septentrionalis Østrup, 1910 accepted as Planothidium septentrionalis (Østrup) Round & Bukhtiyarova, 1996
- Species Achnanthes seriata C.Agardh, 1827
- Species Achnanthes siamexilis Lange-Bertalot in Lange-Bertalot & Krammer, 1989
- Species Achnanthes siamlinearis Lange-Bertalot in Lange-Bertalot & Krammer, 1989
- Species Achnanthes sibayiensis Archibald, 1966 accepted as Madinithidium sibayiensis (R.E.M. Archibald) De Ridder & J.C. Taylor, 2020
- Species Achnanthes siberica Cleve-Euler, 1953
- Species Achnanthes sigmoides Ehrenberg, 1873
- Species Achnanthes silvahercynia Lange-Bertalot, 1989 accepted as Nupela silvahercynia (Lange-Bertalot) Lange-Bertalot in Lange-Bertalot & Metzeltin, 1996
- Species Achnanthes similis McCall, 1933
- Species Achnanthes similis Hustedt, 1935
- Species Achnanthes similivalvata Manguin, 1952
- Species Achnanthes simplex Hustedt, 1939
- Species Achnanthes simplex (Peragallo) Frenguelli & Orlando, 1958 accepted as Achnanthepyla simplex Perag., 1921
- Species Achnanthes sinuata Kützing according to M. Peragallo
- Species Achnanthes skvortzowii Jasnitsky, 1936
- Species Achnanthes skvortzowii Hustedt in Schmidt et al., 1958
- Species Achnanthes smithiana (Greville) K.Toyoda & D.M.Williams, 2005 accepted as Monogramma smithiana Greville, 1866
- Species Achnanthes solea Zimmermann, 1917
- Species Achnanthes solea Hustedt, 1952
- Species Achnanthes sonyda B.Hartley, 1986
- Species Achnanthes soodensis (Krasske) Cleve-Euler, 1953 accepted as Navicula soodensis var. soodensis Krasske, 1927
- Species Achnanthes speciosa Hustedt, 1927 accepted as Haloroundia speciosa (Hustedt) Diaz & Maidana
- Species Achnanthes sperata Cholnoky, 1962
- Species Achnanthes sphacelata Carter, 1970
- Species Achnanthes spiculata K.E. Lohman, 1957
- Species Achnanthes standeri Cholnoky, 1957
- Species Achnanthes stauroneiformis Skabichevskij, 1936
- Species Achnanthes stauroneiformis Prowse, 1962
- Species Achnanthes stauroneioides Manguin in Bourrelly & Manguin, 1954
- Species Achnanthes stewartii Patrick, 1945
- Species Achnanthes stipitata (Lyngbye) Ehrenberg, 1834
- Species Achnanthes stolida (Krasske) Krasske, 1949
- Species Achnanthes stomatimorpha Turpin, 1828
- Species Achnanthes stomatophora ‘Turpin' VanLandingham, 1979
- Species Achnanthes straubiana Lange-Bertalot, 1996
- Species Achnanthes strenzkei (Hustedt) Simonsen, 1987 accepted as Navicula strenzkei Hustedt, 1962
- Species Achnanthes striata Skvortzov, 1937
- Species Achnanthes striata ‘Chase', 1885
- Species Achnanthes striata [Suhr], Drège, 1843
- Species Achnanthes striata Suhr ms., Kützing, 1844
- Species Achnanthes striatella Skvortzov, 2012
- Species Achnanthes stroemii Hustedt, 1933
- Species Achnanthes subaffinis Cholnoky, 1959
- Species Achnanthes subatomoides (Hustedt) Lange-Bertalot & Archibald, 1985 accepted as Navicula subatomoides Hustedt, 1936
- Species Achnanthes subatomus Hustedt, 1939
- Species Achnanthes subconstricta (Meister) Toyoda accepted as Achnanthes javanica var. subconstricta Meister, 1932
- Species Achnanthes subcrassa Maillard ex Lange-Bertalot & Steidorf in Moser, Steindorf & Lange-Bertalot, 1995
- Species Achnanthes subcrassa Maillard, 1978
- Species Achnanthes subcrenulata Cleve, 1891
- Species Achnanthes subelata D. Metzeltin, H. Lange-Bertalot & F. García-Rodríguez, 2005
- Species Achnanthes subexigua Hustedt, 1934
- Species Achnanthes subfragilis (Skvortzov)
- Species Achnanthes subhastata (Skvortzov)
- Species Achnanthes subhudsonis Hustedt, 1921 accepted as Achnanthidium subhudsonis (Hustedt) H.Kobayasi, 2006
- Species Achnanthes subhungarica (Gutwinski) De Toni, 1890 accepted as Achnanthidium subhungaricum Gutwinski, 1890
- Species Achnanthes subhyalina Conger, 1964
- Species Achnanthes subinflata (Østrup) Cleve-Euler, 1953 accepted as Achnanthes lanceolata var. subinflata Østrup, 1918
- Species Achnanthes sublaevis Hustedt, 1937
- Species Achnanthes sublevanderi Manguin, 1949
- Species Achnanthes sublevanderi Manguin emend Schoeman, 1970
- Species Achnanthes sublinearis Skvortzov
- Species Achnanthes sublitoralis Skabichevskii, 1976
- Species Achnanthes submarina Hustedt, 1956
- Species Achnanthes submontana Gandhi, 1970
- Species Achnanthes subquadrata (Pantocsek) Tempère & Peragallo, 1909 accepted as Achnanthes baldjicki var. subquadrata Pant., 1892 †
- Species Achnanthes subrostrata Hustedt, 1942
- Species Achnanthes subsalsa J.B.Petersen, 1928
- Species Achnanthes subsalsoides Hustedt, 1933
- Species Achnanthes subsaxonica Cholnoky, 1960
- Species Achnanthes subsenilis
- Species Achnanthes subsessilis Kützing, 1833 accepted as Achnanthes brevipes var. intermedia (Kützing) Cleve, 1895
- Species Achnanthes subtropica Cholnoky, 1960
- Species Achnanthes subventricosa Grunow ex Cleve & Möller, 1877
- Species Achnanthes suchlandtii Hustedt, 1933 accepted as Karayevia suchlandtii (Hustedt) Buktiyarova, 1999
- Species Achnanthes sumara Carter, 1966
- Species Achnanthes suspecta A.Cleve, 1934
- Species Achnanthes sutura Carter, 1970
- Species Achnanthes swazi Cholnoky, 1960
- Species Achnanthes taeniata Grunow, 1880 accepted as Pauliella taeniata (Grunow) F.E.Round & P.W.Basson, 1997
- Species Achnanthes taeniata Gran, 1897
- Species Achnanthes taiaensis Carter & Denny, 1982
- Species Achnanthes tanensis Cleve-Euler, 1934
- Species Achnanthes tatrensis Starmach, 1973
- Species Achnanthes taylorensis D.E. Kellogg, M. Stuiver, T.B. Kellogg & G.H. DEnton, 1980
- Species Achnanthes temperei M.Peragallo, 1908
- Species Achnanthes tenera Hustedt, 1955
- Species Achnanthes tenuis Hustedt, 1955
- Species Achnanthes tenuissima Pantocsek, 1902
- Species Achnanthes tenuissima Hustedt, 1937 accepted as Nupela biconfusa (VanLandingham) C.E.Wetzel & Ector, 2018
- Species Achnanthes tenuistauros Mann, 1925
- Species Achnanthes tenuistriata Hustedt, 1952 accepted as Nupela tenuistriata (Hustedt) Metzeltin & Lange-Bertalot, 1998
- Species Achnanthes terrae-novae Woodhead & Tweed, 1960
- Species Achnanthes teshekpukensis Foged, 1968
- Species Achnanthes therezienii Lange-Bertalot & Krammer, 1989
- Species Achnanthes thermalis (Rabenhorst) Schoenfeld, 1907 accepted as Achnanthidium thermale Rabenhorst, 1864
- Species Achnanthes thienemannii Hustedt, 1942
- Species Achnanthes tibetica Jao, 1964
- Species Achnanthes trachyderma (F.Meister, 1934)
- Species Achnanthes triconfusa Van Landingham, 1967
- Species Achnanthes trigibba Hustedt ex Simonsen, 1987
- Species Achnanthes trigibba Hustedt in Schmidt et al., 1937
- Species Achnanthes trigibba Hustedt ex Gandhi, 1970
- Species Achnanthes trijuga ‘Turpin' according to VanLandingham, 1828
- Species Achnanthes trinodis (W.Smith) Grunow, 1880
- Species Achnanthes trinodis (Ralfs) Grunow, 1880 accepted as Achnanthidium trinode Ralfs, 1861
- Species Achnanthes trinodis Ehrenberg, 1870
- Species Achnanthes tropica Hustedt, 1937 accepted as Nupela tropica (Hustedt) Lange-Bertalot, 1999
- Species Achnanthes tuma Carter, 1970
- Species Achnanthes tumescens A.R.Sherwood & R.L.Lowe, 2009
- Species Achnanthes turgens Ehrenberg, 1843
- Species Achnanthes turgida Ehrenberg, 1853
- Species Achnanthes tylophora (Reichelt) Heiden in A. Schmidt, 1903 accepted as Stauroneis tylophora Reichelt, 1903
- Species Achnanthes ubiqua Maidana, 1986
- Species Achnanthes umara J.R.Carter, 1970
- Species Achnanthes undata Meister, 1934
- Species Achnanthes undulata (Schumann) De Toni, 1891 accepted as Achnanthidium undulatum Schumann, 1867
- Species Achnanthes undulatus Sreenivasa, 1971
- Species Achnanthes undulorostrata R.L.Lowe & A.R.Sherwood, 2009
- Species Achnanthes unipunctata (Lyngbye) Greville accepted as Fragilaria unipunctata Lyngbye, 1819
- Species Achnanthes unipunctatus Missuna, 1914
- Species Achnanthes utukakensis Patrick & Freese, 1961
- Species Achnanthes valida Hustedt ex R.Simonsen, 1987
- Species Achnanthes vanhoffenii Heiden in Heiden & Kolbe, 1928
- Species Achnanthes vasta Pantocsek, 1902
- Species Achnanthes vaszaryi (Pantocsek) Cleve
- Species Achnanthes veccillum Bory, 1832
- Species Achnanthes ventralis (Krasske) Lange-Bertalot, 1989 accepted as Navicula ventralis Krasske, 1923
- Species Achnanthes ventricosa Kützing, 1844
- Species Achnanthes ventricosa Ehrenberg, 1854
- Species Achnanthes vernalis Pantocsek, 1902
- Species Achnanthes vexillum Bory, 1832
- Species Achnanthes vicentii Manguin, 1957
- Species Achnanthes vistulana A. Witkowski, 1994
- Species Achnanthes volhyniensis Oksiyuk, 1957
- Species Achnanthes wellsiae Reimer, 1966
- Species Achnanthes wickenensis J.R.Carter, 1963
- Species Achnanthes woldstedtii Hustedt, 1954
- Species Achnanthes wolffii Foged, 1957
- Species Achnanthes woltereckii Hustedt, 1942 accepted as Achnanthidium woltereckii (Hustedt) Lange-Bertalot, 1999
- Species Achnanthes woodlawnensis Playfair, 1915
- Species Achnanthes wrightiana Woodhead & Tweed, 1960
- Species Achnanthes yabe Skvortzow, 1937 accepted as Achnanthes exigua var. yabeana Skvortzov
- Species Achnanthes yaquinensis McIntire & Reimer, 1974
- Species Achnanthes yeniseyensis Skvortzow, 1971
- Species Achnanthes ziegleri Lange-Bert., 1993
- Species Achnanthes ziegleri Lange-Bert. in Krammer & Lange-Bertalot in H. Ettl et al., 1991
- Genus Amphicocconeis M. De Stephano & D. Marino, 2002 (3)
- Genus Haloroundia C.A.Düaz & N.I.Maidana, 2006 (1)
- Genus Platebaikalia Kulikovskiy, Glushchenko, Genkal & Kociolek, 2020 (1)
- Genus Platessa H. Lange-Bertalot, 2004 (17)
- Family Achnanthidiaceae D.G. Mann, 1990 (244)
- Family Cocconeidaceae Kützing, 1844 (83)
- Order Bacillariales (357)
- Order Cymbellales (792)
- Order Dictyoneidales
- Order Lyrellales (15)
- Order Mastogloiales (88)
- Order Naviculales (2 077)
- 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
