DiatomBase
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- Bacillariophyceae (5 957)
- Subclass Bacillariophyceae incertae sedis (189)
- Subclass Bacillariophycidae (4 408)
- Subclass Coscinodiscophycidae (877)
- Superorder Biddulphianae (230)
- Order Anaulales (7)
- Order Biddulphiales (38)
- Family Biddulphiaceae Kützing, 1844 (37)
- Genus Alveoflexus N.I. Hendey & P.A. Sims, 1984 †
- Genus Ancoropsis N.I. Hendey & P.A. Sims, 1984 †
- Genus Arcusidiscus S.Komura, 2008
- Genus Biddulphia S.F. Gray, 1821 (24)
- Species Biddulphia abjecta Mann, 1925
- Species Biddulphia abyssorum
- Species Biddulphia acanthoceros Forti, 1913
- Species Biddulphia acuta (Ehrenberg) Boyer, 1900 accepted as Triceratium acutum Ehrenberg, 1844 (1845)
- Species Biddulphia advena VanLandingham, 1968
- Species Biddulphia affinis (Grunow in Van Heurck) Van Heurck, 1909 accepted as Triceratium affine Grunow in Van Heurck, 1883
- Species Biddulphia africana Leuduger-Fortmorel, 1898
- Species Biddulphia agulhas Karsten, 1905
- Species Biddulphia alaskiensis Mann, 1907
- Species Biddulphia alternans (Bailey) Van Heurck, 1885 accepted as Trigonium alternans (Bailey) A.Mann, 1907
- Species Biddulphia americana (Ralfs in Pritchard) Boyer, 1900 accepted as Triceratium americanum var. americanum Ralfs in Pritchard, 1861
- Species Biddulphia amphicephala (Ehrenberg) Ralfs in Pritchard, 1861 accepted as Odontella amphicephala Ehrenberg, 1845
- Species Biddulphia angulata Schmidt in Schmidt et al., 1888
- Species Biddulphia antarctica ‘Cleve' Mills
- Species Biddulphia antarctica (Ehrenberg) M. Peragallo, 1897 accepted as Hemiaulus antarcticus Ehrenberg, 1844
- Species Biddulphia antediluviana (Ehrenberg) Van Heurck, 1885
- Variety Biddulphia antediluviana var. antediluviana (Ehrenberg) Van Heurck, 1885 accepted as Amphitetras antediluviana var. antediluviana Ehrenberg, 1840
- Variety Biddulphia antediluviana var. cruciformis ‘W. Smith' according to Mills
- Variety Biddulphia antediluviana var. excavata "Adam's Collection" according to Mills
- Variety Biddulphia antediluviana var. excavata Frenguelli, 1945
- Variety Biddulphia antediluviana var. minor (H. Peragallo & M. Peragallo) F.W. Mills accepted as Amphitetras antediluviana var. minor Peragallo & Peragallo, 1902
- Variety Biddulphia antediluviana var. minutum (Greville) F.W. Mills, 1933 accepted as Amphitetras minuta Greville, 1861
- Variety Biddulphia antediluviana var. nobilis “Adam's Collection” according to F.W. Mills
- Variety Biddulphia antediluviana var. ornata Hendey, 1971
- Variety Biddulphia antediluviana var. pentagona (Hustedt) F.W. Mills, 1933 accepted as Triceratium antediluvianum f. pentagona Hustedt, 1930
- Variety Biddulphia antediluviana var. tesselata (Shadbolt) F.W. Mills, 1933 accepted as Amphitetras tessellata Shadbolt, 1854
- Variety Biddulphia antediluviana var. trigona (M. Peragallo in Tempère & Peragallo) F.W. Mills, 1933 accepted as Triceratium antediluvianum var. trigona M. Peragallo in Peragallo & Peragallo, 1911
- Species Biddulphia antediluviana ‘Azpeitia y Moros' Mills, 1911
- Species Biddulphia anthropomorpha Van Heurck, 1909
- Species Biddulphia antillarum (Cleve) Boyer, 1900 accepted as Triceratium antillarum var. antillarum Cleve, 1878
- Species Biddulphia antiqua Truan y Luard & Witt, 1888
- Species Biddulphia apiculata Long, Fuge & Smith, 1946
- Species Biddulphia arctica (Brightwell) Boyer, 1901 accepted as Trigonium arcticum (Brightwell) Cleve, 1868
- Species Biddulphia arcuata (Shadbolt) F.W. Mills, 1933 accepted as Triceratium arcuatum Shadbolt, 1854
- Species Biddulphia areolata Hajós, 1968
- Species Biddulphia argus Boyer, 1898
- Species Biddulphia armata Leuduger-Fortmorel, 1879
- Species Biddulphia astrolabensis Hendey, 1937
- Species Biddulphia auliscoformis Strelnikova, 1964
- Species Biddulphia aurita (Lyngbye) Brébisson, 1838 accepted as Odontella aurita (Lyngbye) C.Agardh, 1832
- Species Biddulphia australis Montagne, 1842
- Species Biddulphia azorica J.Pavillard, 1908
- Species Biddulphia bailey W. Smith, 1856 accepted as Biddulphia mobiliensis (J.W.Bailey) Grunow, 1882
- Species Biddulphia baileyii W. Smith, 1856
- Species Biddulphia balaena (Ehrenberg) T.Brightwell accepted as Zygoceros balaena Ehrenberg, 1853
- Species Biddulphia baldjikii Girard
- Species Biddulphia balearica (Cleve & Grunow) A.Mann, 1925 accepted as Triceratium balearicum f. balearicum Cleve & Grunow in Cleve, 1881
- Species Biddulphia baltzoi Hanna, 1970
- Species Biddulphia barbadensis Greville, 1866
- Species Biddulphia belgicae M.Peragallo
- Species Biddulphia bicorne Cleve, 1878
- Species Biddulphia bicornis Cleve, 1878
- Species Biddulphia biddulphiana (J.E.Smith) Boyer, 1900
- Species Biddulphia bifasciata Wigand, 1860
- Species Biddulphia bifenestra Brun, 1896
- Species Biddulphia bipons ‘Ehrenberg' Mills, 1933
- Species Biddulphia biquadrata (Janisch in Schmidt et al.) Boyer, 1900 accepted as Triceratium biquadratum Janisch, 1886
- Species Biddulphia birostrata Grunow, 1863
- Species Biddulphia birostrum Brun, 1891
- Species Biddulphia blanda Schmidt in Schmidt et al., 1888
- Species Biddulphia boryana ‘Pantocsek' Mills, 1933
- Species Biddulphia brachiolatum (Brightwell) Taylor, 1970 accepted as Triceratium brachiolatum Brightwell, 1853
- Species Biddulphia brevis Ehrenberg, 1845
- Species Biddulphia brittoniana C.H.Kain & E.A.Schultze, 1889 †
- Species Biddulphia broeckii (Leuduger-Fortmorel) Mann, 1925 accepted as Triceratium broeckii Leuduger-Fortmorel, 1879
- Species Biddulphia calamus Tempère & Brun, 1889 †
- Species Biddulphia californica (Schmidt) Boyer, 1901 accepted as Cerataulus californicus Schmidt in Schmidt et al., 1888
- Species Biddulphia campeachiana (Grunow) Boyer, 1900 accepted as Triceratium campechianum Grunow in Cleve, 1878
- Species Biddulphia capuzina Schmidt, 1888
- Species Biddulphia caraibica Truan y Luard & Witt, 1888
- Species Biddulphia castellifera (Grunow) Mann, 1925 accepted as Triceratium castelliferum A.Grunow, 1888 †
- Species Biddulphia catenata Schussnig, 1915
- Species Biddulphia cayennensis Ehrenberg, 1854
- Species Biddulphia centralis Boyer, 1922
- Species Biddulphia challengerii Tsumura, 1969
- Species Biddulphia chinensis Greville, 1866
- Species Biddulphia cingulata Mann, 1925
- Species Biddulphia circinus (Bailey) Van Heurck, 1896 accepted as Zygoceros circinus var. circinus J.W. Bailey, 1854
- Species Biddulphia cirrus Ehrenberg, 1847
- Species Biddulphia clavulata Ehrenberg, 1861
- Species Biddulphia clypeolus Boyer, 1922
- Species Biddulphia concava Mann, 1925
- Species Biddulphia concinnus Van Heurck, 1896
- Species Biddulphia condecora (Ehrenberg) Boyer, 1900 accepted as Triceratium condecorum var. condecorum Ehrenberg, 1844 (1845)
- Species Biddulphia connecta Wood, 1963
- Species Biddulphia consimilis (Grunow in Van Heurck) Boyer, 1900 accepted as Triceratium consimile Grunow in Van Heurck, 1883
- Species Biddulphia contorta Karsten, 1905
- Species Biddulphia convexa Mann, 1937
- Species Biddulphia convexiuscula (Grunow in Schmidt et al.) Boyer, 1900 accepted as Triceratium convexiusculum Grunow in Schmidt et al., 1890
- Species Biddulphia cookiana Kain & Schultze, 1889
- Species Biddulphia cornigera Mann, 1925
- Species Biddulphia cornucaprae Brun, 1894
- Species Biddulphia cornuta Brun, 1894
- Species Biddulphia cornuta (Greville) Mann, 1925 accepted as Triceratium cornutum R.K.Greville †
- Species Biddulphia corpulenta Greville, 1865
- Species Biddulphia coruscans Schmidt in Schmidt et al., 1888
- Species Biddulphia costata Boyer, 1922
- Species Biddulphia costulata (Grunow in Schmidt et al.) Boyer, 1900 accepted as Triceratium tumidum var. costulata Grunow in Schmidt et al., 1882
- Species Biddulphia crassiuscula Pantocsek, 1892
- Species Biddulphia crenulata Walker in Walker & Chase, 1886
- Species Biddulphia cretacea Hajós & Stradner, 1974
- Species Biddulphia cretacea Brun, 1896
- Species Biddulphia cristata Grunow in Van Heurck, 1882
- Species Biddulphia cruciata Petit, 1908
- Species Biddulphia culcitella Mann, 1907
- Species Biddulphia curvata Hendey & Sims, 1984
- Species Biddulphia curvinervia C.S.Boyer, 1922 † accepted as Entogoniopsis curvinervia (C.S.Boyer) J.Witkowski, P.A.Sims, N.I.Strelnikova & D.M.Williams, 2015 †
- Species Biddulphia cuspidata (Janisch in Schmidt et al.) Mann, 1925 accepted as Triceratium cuspidatum Janisch in Schmidt et al., 1885
- Species Biddulphia cycloides Mann, 1925
- Species Biddulphia cylindrata Wood, Crosby & Cassie, 1959
- Species Biddulphia cylindrus Weisse, 1867
- Species Biddulphia damanuensis Christian, 1888
- Species Biddulphia decipiens Grunow in Van Heurck, 1882
- Species Biddulphia decorata Greville, 1865
- Species Biddulphia decumana Schmidt in Schmidt et al., 1892
- Species Biddulphia decussata Strelnikova, 1965
- Species Biddulphia deodora Hanna & Grant, 1926
- Species Biddulphia discigera Grunow
- Species Biddulphia discursa Mann, 1925
- Species Biddulphia dissipata Grove & Sturt, 1887
- Species Biddulphia distincta (Janisch in Schmidt et al.) Mann, 1925 accepted as Triceratium distinctum var. distinctum Janisch in Schmidt et al., 1885
- Species Biddulphia divisa Grunow in Van Heurck, 1883
- Species Biddulphia dubia (T.Brightwell) Cleve, 1883 accepted as Pseudictyota dubium (Brightwell) P.A. Sims & D. M. Williams in Sims et al., 2018
- Species Biddulphia echinata Kitton, 1888
- Species Biddulphia echinulata Jousé in Proschkina-Lavrenko, 1949
- Species Biddulphia ecornuta Strelnikova, 1974
- Species Biddulphia edwardsii Febiger ex Grunow, 1882
- Species Biddulphia elaborata Grove & Sturt, 1886
- Species Biddulphia elegans (Greville) Boyer, 1900 accepted as Amphitetras elegans Greville, 1866
- Species Biddulphia elegantula Greville
- Species Biddulphia elesdiana Pantocsek, 1889
- Species Biddulphia elongata Meneghini in Kützing, 1849
- Species Biddulphia eulensteinii (Grunow in A. Schmidt) Grunow in Van Heurck, 1896 accepted as Triceratium eulensteinii var. eulensteinii Grunow in Schmidt et al., 1882
- Species Biddulphia exacta Mann, 1925
- Species Biddulphia eximia (Grunow) Laporte & Lefébure, 1930 † accepted as Syringidium eximium A.Grunow in H.Van Heurck, 1883 †
- Species Biddulphia expedita Janisch in Schmidt et al., 1888
- Species Biddulphia extensa Mann, 1907
- Species Biddulphia falcata Boyer, 1922
- Species Biddulphia favus (Ehrenberg) Van Heurck, 1885 accepted as Triceratium favus Ehrenberg, 1839
- Species Biddulphia fenestrata (Grove & Sturt) Grunow in Schmidt et al., 1888 accepted as Auliscus fenestratus Grove & Sturt, 1887
- Species Biddulphia fimbriata (Wallich) Mann, 1925 accepted as Triceratium fimbriatum Wallich, 1858
- Species Biddulphia fimbriata Greville, 1865 † accepted as Parodontella fimbriata (Greville) D. M. Williams & P.A. Sims in Sims et al., 2018 †
- Species Biddulphia fistulosa Pantocsek, 1892
- Species Biddulphia flos (Ehrenberg) Grunow
- Species Biddulphia formosa (Brightwell) E. Jörgensen, 1905 accepted as Trigonium formosum (Brightwell) Cleve, 1867
- Species Biddulphia fortiana Tempère in Forti, 1913
- Species Biddulphia fossa Grove & Sturt, 1887
- Species Biddulphia fractosa Mann, 1925
- Species Biddulphia fragilaria (Ehrenberg) Ralfs in Pritchard, 1861 accepted as Denticella fragilaria Ehrenberg, 1844
- Species Biddulphia fragilis Bone & Gosden, 1967
- Species Biddulphia frauenfeldii Grunow in Van Heurck, 1883
- Species Biddulphia frickei Van Heurck, 1909
- Species Biddulphia fulva Boyer, 1922
- Species Biddulphia gallapagensis Cleve, 1881
- Species Biddulphia gemina (Schmidt in Schmidt et al.) Mann, 1925 accepted as Triceratium geminum Schmidt in Schmidt et al., 1882
- Species Biddulphia gibbosa
- Species Biddulphia gigantea Greville, 1864
- Species Biddulphia gigas Ehrenberg, 1844
- Species Biddulphia gladiorum A.Mann, 1907
- Species Biddulphia grandicornis Tsumura, 1969
- Species Biddulphia grandis (Brightwell) Boyer, 1900 accepted as Triceratium grande f. grande Brightwell, 1853
- Species Biddulphia granulata Roper, 1859 † accepted as Cerataulus granulatus (Roper) P.A. Sims & D.M. Williams, 2018 †
- Species Biddulphia grovei Pantocsek, 1892
- Species Biddulphia gruendleri Schmidt in Schmidt et al., 1888
- Species Biddulphia grunowiana (Castracane) Mann, 1925 accepted as Triceratium grunowianum Castracane, 1886
- Species Biddulphia gurowii Pantocsek, 1892
- Species Biddulphia hamata ‘Pantocsek' De Toni, 1886
- Species Biddulphia hebetata (Grunow in Van Heurck) Boyer, 1900 accepted as Triceratium irregulare var. hebetata Grunow in Van Heurck, 1883
- Species Biddulphia heibergii H.F.Van Heurck
- Species Biddulphia heilpriniana (Kain & E.A. Schultze) Boyer, 1900 accepted as Triceratium heilprinianum Kain & Schultze, 1889
- Species Biddulphia hemitropa L.W. Bailey, 1862
- Species Biddulphia heteroceros Grunow in Van Heurck, 1882
- Species Biddulphia heteromorpha T.F.Kozyrenko in T.F.Kozyrenko, A.P.Jousé & O.G.Kozlova, 1977 †
- Species Biddulphia heteropora (Grunow in Van Heurck) Boyer, 1900 accepted as Triceratium heteroporum Grunow in Van Heurck, 1883
- Species Biddulphia hexagonalis Boyer, 1922
- Species Biddulphia homala Pantocsek
- Species Biddulphia hyalina Schröder, 1906
- Species Biddulphia hyalina Peragallo in Tempère & Peragallo, 1909
- Species Biddulphia immanis Boyer, 1922
- Species Biddulphia imperialis Walker in Walker & Chase, 1886
- Species Biddulphia impressa Long, Fuge & Smith, 1946
- Species Biddulphia impressa (Grunow) Mann, 1925 accepted as Triceratium impressum Grunow, 1883
- Species Biddulphia includens Ehrenberg, 1855
- Species Biddulphia indica (Ehrenberg) Roper, 1859 accepted as Denticella indica Ehrenberg, 1845
- Species Biddulphia inelegans (Greville) C.S.Boyer
- Species Biddulphia inflata Greville
- Species Biddulphia informis Mann, 1925
- Species Biddulphia infundibuloides Desikachary, Gowthaman & Latha, 1987
- Species Biddulphia insignis (Greville) Mann, 1925 accepted as Triceratium insigne f. insignis Greville, 1861
- Species Biddulphia interpunctata (Grunow in Schmidt et al.) Boyer, 1900 accepted as Triceratium interpunctatum Grunow in Schmidt et al., 1882
- Species Biddulphia interrupta Boyer, 1898
- Species Biddulphia inusitata Hohn & Hellerman, 1966 accepted as Pleurosira inusitata (Hohn & Hellerman) Desianti & Potapova, 2015
- Species Biddulphia inversa ‘Mann' Mills, 1925
- Species Biddulphia inverta Mann, 1925
- Species Biddulphia irregulare
- Species Biddulphia japonica Castracane, 1886
- Species Biddulphia japonica Pantocsek, 1892
- Species Biddulphia jimboi Pantocsek, 1903
- Species Biddulphia johnsoniana Greville, 1866
- Species Biddulphia jordani Hanna & Grant, 1926
- Species Biddulphia jucatensis (Grunow in Schmidt et al.) Boyer, 1927 accepted as Triceratium jucatense Grunow in Schmidt et al., 1882
- Species Biddulphia juncatensis (Grunow) Mann, 1925 accepted as Triceratium jucatense Grunow in Schmidt et al., 1882
- Species Biddulphia juncta (A.Schmidt) A.Mann, 1925
- Species Biddulphia kainii (E.A. Schultze in Kain & E.A. Schultze) Boyer, 1900 accepted as Triceratium kainii E.A.Schultze in Kain & Schultze, 1889 †
- Species Biddulphia keeleyi Boyer, 1898
- Species Biddulphia kemnae Van Heurck, 1909
- Species Biddulphia lacunosa Long, Fuge & Smith, 1946
- Species Biddulphia laevis Ehrenberg, 1843
- Species Biddulphia lata (Greville) E. Jørgensen, 1905 accepted as Triceratium latum var. latum Greville, 1865
- Species Biddulphia lata Grove & Sturt, 1886-1887
- Species Biddulphia levigata Sheshukova-Poretskaya, 1967
- Species Biddulphia levis Ehrenberg, 1843
- Species Biddulphia litigiosa Van Heurck, 1909
- Species Biddulphia lóczyi Pantocsek, 1889
- Species Biddulphia longaeva Long, Fuge & Smith, 1946
- Species Biddulphia longicornis Skvortzow, 1931
- Species Biddulphia longicruris Greville, 1859 accepted as Hobaniella longicruris (Greville) P.A. Sims & D.M. Williams in Sims et al., 2018
- Species Biddulphia longispina Grunow in Van Heurck, 1882
- Species Biddulphia luminosa (J.-J.Brun & J.A.Tempère) A.Mann accepted as Triceratium luminosum Tempère & Brun in Brun & Tempère, 1889
- Species Biddulphia lunaris ‘Auctorum' according to Mills
- Species Biddulphia lunata Ehrenberg, 1844
- Species Biddulphia macdonaldii Norman in Pritchard, 1861
- Species Biddulphia madagascarensis (Grunow in Van Heurck) Mann, 1925 accepted as Triceratium madagascarense Grunow in Van Heurck, 1883
- Species Biddulphia majus (Grove & Sturt) † accepted as Entogoniopsis major J.Witkowski, P.A.Sims, N.I.Strelnikova & D.M.Williams, 2015 †
- Species Biddulphia mammosa Greville, 1866
- Species Biddulphia manca Janisch in Schmidt et al., 1888
- Species Biddulphia media H. Peragallo in Tempère & Peragallo, 1909
- Species Biddulphia mediterranensis ‘Grunow' Mills
- Species Biddulphia membranacea Cleve, 1878
- Species Biddulphia minima Schiller in Hustedt, 1930
- Species Biddulphia minuta (Greville) Andrews, 1988 accepted as Amphitetras minuta Greville, 1861
- Species Biddulphia minutissima Greville, 1886
- Species Biddulphia miraculosa Brun in Schmidt et al., 1892
- Species Biddulphia mobiliensis (J.W.Bailey) Grunow, 1882 accepted as Trieres mobiliensis (J.W.Bailey) Ashworth & E.C.Theriot in Ashworth, Nakov & E.C.Theiriot, 2013
- Species Biddulphia mobiliensis sensu Gran, 1905
- Species Biddulphia moholensis Schrader, 1974
- Species Biddulphia mollis Mann, 1937
- Species Biddulphia montereyi (Brightwell) Mereschkowsky, 1901 accepted as Triceratium montereyi f. montereyi Brightwell, 1853
- Species Biddulphia moronensis (Greville) T.V. Desikachary, 1989 accepted as Triceratium moronense var. moronense Greville, 1865
- Species Biddulphia multicornis Grunow, 1882 † accepted as †
- Species Biddulphia murrayana Hendey, 1939
- Species Biddulphia mythica Tsumura, 1969
- Species Biddulphia nankoorensis ‘Grunow in Van Heurck' M. Peragallo, 1897
- Species Biddulphia neogradensis (Pantocsek) F.W. Mills, 1933 accepted as Odontella neogradensis Pantocsek, 1886
- Species Biddulphia nervata Boyer, 1922
- Species Biddulphia nitida Greville, 1865
- Species Biddulphia nobilis J.-J.Brun
- Species Biddulphia nobilis (Witt) E. Jørgensen, 1905 accepted as Triceratium nobile Witt, 1885
- Species Biddulphia nobilis (Greville) Brockmann, 1928 accepted as Amphitetras nobilis Greville, 1865
- Species Biddulphia novaezealandiae Wise, 1952
- Species Biddulphia oamaruensis Grove & Sturt, 1886
- Species Biddulphia obliquata (J.E. Smith) Gray, 1821
- Species Biddulphia obtusa (Kützing) Ralfs, 1861 accepted as Odontella obtusa Kützing, 1844
- Species Biddulphia obtusa (Ehrenberg) Boyer, 1901 accepted as Triceratium obtusum f. obtusum Ehrenberg, 1844
- Species Biddulphia occidentalis (L.W. Bailey) Wolle, 1890 accepted as Zygoceros occidentalis J.W. Bailey in L.W. Bailey, 1861
- Species Biddulphia orbiculata (Shadbolt) Boyer, 1900 accepted as Triceratium orbiculatum var. orbiculatum Shadbolt, 1854
- Species Biddulphia ornata (Shadbolt) Castracane, 1886 accepted as Amphitetras ornata var. ornata Shadbolt, 1854
- Species Biddulphia ottomuelleri
- Species Biddulphia ovalis (Schmidt in Schmidt et al.) Boyer, 1900 accepted as Cerataulus ovalis Schmidt in Schmidt et al., 1888
- Species Biddulphia pacifica (Grunow in Schmidt et al.) Mann, 1907 accepted as Cerataulus pacificus Grunow in Schmidt et al., 1888
- Species Biddulphia palpebralis Forti in Tempère & Peragallo, 1914
- Species Biddulphia pantocsekites VanLandingham, 1968
- Species Biddulphia papillata (Grove & Sturt) Mann, 1907 accepted as Triceratium papillatum var. papillatum Grove & Sturt, 1887
- Species Biddulphia paradoxa Petit, 1908
- Species Biddulphia parallela Castracane, 1886
- Species Biddulphia parallela ‘Ehrenberg' Grunow in Van Heurck, 1883
- Species Biddulphia parvula (Janisch & Rabenhorst) Boyer, 1900 accepted as Amphitetras parvula Janisch & Rabenhorst, 1863
- Species Biddulphia patagoniana Frenguelli, 1941
- Species Biddulphia patagonica Ehrenberg, 1854
- Species Biddulphia patera Barker & Meakin, 1949
- Species Biddulphia pedalis Grove & Sturt, 1887
- Species Biddulphia pelagica J.L.B.Schröder, 1908
- Species Biddulphia pellucida Castracane, 1886
- Species Biddulphia penitens Hanna & Grant, 1926
- Species Biddulphia pentacrinus (Ehrenberg) Boyer, 1901 accepted as Amphipentas pentacrinus Ehrenberg, 1841 †
- Species Biddulphia peragalli
- Species Biddulphia peragalloi Leuduger-Fortmorel, 1898
- Species Biddulphia permagna Pantocsek, 1889
- Species Biddulphia permagna (Janisch) Van Heurck, 1909 accepted as Triceratium permagnum Janisch, 1888
- Species Biddulphia perplexa Long, Fuge & Smith, 1946
- Species Biddulphia perpusilla J.W. Bailey Collection according to Chase, 1885
- Species Biddulphia peruviana Grunow in Van Heurck, 1882 † accepted as Ralfsiella peruviana (Grunow in Van Heurck) P.A. Sims, D. M. Williams & M. Ashworth, 2018 †
- Species Biddulphia petitiana (Leuduger-Fortmorel) Mann, 1925 accepted as Triceratium petitianum Leuduger-Fortmorel, 1898
- Species Biddulphia petitii (Leuduger-Fortmorel) Mann, 1925 accepted as Cerataulus petitii Leuduger-Fortmorel, 1892
- Species Biddulphia petrolia Hanna, 1927
- Species Biddulphia phallus Leuduger-Fortmorel, 1898
- Species Biddulphia picturatum (Greville) Taylor, 1970 accepted as Triceratium picturatum R.K.Greville, 1866 †
- Species Biddulphia plana Schmidt in Schmidt et al., 1888 accepted as Pseudictyota plana (A. Schmidt) P.A. Sims & D. M. Williams in Sims et al., 2018
- Species Biddulphia plicata Grunow in Van Heurck, 1883
- Species Biddulphia podagrosa Greville, 1866
- Species Biddulphia polyacanthos Brun, 1891
- Species Biddulphia polymera (Ehrenberg) Ralfs in Pritchard, 1861 accepted as Denticella polymera Ehrenberg, 1844 (1845)
- Species Biddulphia polymorpha Manguin, 1915
- Species Biddulphia polymorpha (Montagne) Mann, 1925 accepted as Isthmia polymorpha Montagne, 1840
- Species Biddulphia primordialis J.-J.Brun
- Species Biddulphia primordinalis Long, Fuge & Smith, 1946
- Species Biddulphia pulchella S.F.Gray, 1821 accepted as Biddulphia biddulphiana (J.E.Smith) Boyer, 1900
- Species Biddulphia pulchella sensu Möller, 1892
- Species Biddulphia pulverulenta Mann, 1937
- Species Biddulphia pumila Castracane, 1886
- Species Biddulphia punctata Greville
- Species Biddulphia punctata (Brightwell) Van Heurck, 1896 accepted as Triceratium punctatum f. punctatum Brightwell, 1856
- Species Biddulphia punctata Grove & Sturt ex Brun, 1896
- Species Biddulphia pustulata Brun, 1891
- Species Biddulphia pygmea Mann, 1925
- Species Biddulphia quadrans Boyer, 1922
- Species Biddulphia quadricornis (Grunow) Boyer, 1901 accepted as Zygoceros quadricornis Grunow in Van Heurck, 1883
- Species Biddulphia quinquelocularis Kützing, 1844
- Species Biddulphia radialis Andrews, 1986
- Species Biddulphia radiata Roper, 1859
- Species Biddulphia radiata W.Smith accepted as Eupodiscus radiatus W. Smith, 1853
- Species Biddulphia radiata (Brightwell) Grunow in Van Heurck, 1883 accepted as Triceratium radiatum var. radiatum Brightwell, 1856
- Species Biddulphia radiopunctata ‘Mann' according to Mills, 1933
- Species Biddulphia radiosoreticulata Grunow in Van Heurck, 1883
- Species Biddulphia regia (Schultze) Ostenfeld, 1908 accepted as Trieres regia (M.Schultze) M.P.Ashworth & E.C.Theriot, 2013
- Species Biddulphia regina W.Smith, 1856
- Species Biddulphia repleta
- Species Biddulphia reticulata Roper, 1859 accepted as Pseudictyota reticulata (Roper) P.A. Sims & D. M. Williams in Sims et al., 2018
- Species Biddulphia reticulum (Ehrenberg) Boyer, 1900 accepted as Triceratium reticulum f. reticulum Ehrenberg, 1844
- Species Biddulphia retiformis Mann, 1925
- Species Biddulphia reversa Grove & Sturt, 1887
- Species Biddulphia rhombus (Ehrenberg) W.Smith, 1854
- Species Biddulphia riedyi G D.Hanna & W.M.Grant, 1926 † accepted as Entogoniopsis tabellaria (T.Brightwell) J.Witkowski, P.A.Sims, N.I.Strelnikova & D.M.Williams, 2015
- Species Biddulphia rigida A.Schmidt, 1888 †
- Species Biddulphia robertsiana (Greville) C.S.Boyer
- Species Biddulphia robusta Pantocsek, 1889
- Species Biddulphia roperiana Greville, 1859 accepted as Biddulphia obtusa (Kützing) Ralfs, 1861
- Species Biddulphia rossica Pantocsek, 1889
- Species Biddulphia rostrata F.Hustedt
- Species Biddulphia rotunda M. Peragallo in Tempère & Peragallo, 1908
- Species Biddulphia rotundata Janisch, 1888
- Species Biddulphia rudis Mann, 1925
- Species Biddulphia russica Pantocsek, 1889
- Species Biddulphia rustica (Mann) Boyer, 1927 accepted as Trigonium rusticum Mann, 1907
- Species Biddulphia ruthenica Witt, 1885 † accepted as Parodontella ruthenica (Witt) D M.Williams & P.A.Sims in Sims et al., 2018 †
- Species Biddulphia sanpedroana Mereschkowsky, 1900
- Species Biddulphia sansibarica A. Schmidt in Schmidt et al., 1888
- Species Biddulphia saratoviana Pantocsek, 1889
- Species Biddulphia schmidtii (C.Janisch) A.Mann
- Species Biddulphia schroederiana Schüssnig, 1915
- Species Biddulphia scitula Mann, 1925
- Species Biddulphia sculpta (Shadbolt) Van Heurck, 1885 accepted as Triceratium sculptum var. sculptum Shadbolt, 1854
- Species Biddulphia scutellum Mann, 1907
- Species Biddulphia scutum Bone & Gosden, 1967
- Species Biddulphia secedens (Schmidt in Schmidt et al.) Mann, 1925 accepted as Triceratium secedens Schmidt in Schmidt et al., 1888
- Species Biddulphia semicircularis (Brightwell) C.S.Boyer accepted as Euodiella semicircularis (Brightwell) P.A.Sims, 2000 †
- Species Biddulphia sentum (Witt in Schmidt et al.) Van Heurck, 1909 accepted as Triceratium sentum f. sentum Witt in Schmidt et al., 1890
- Species Biddulphia separanda Janisch in Schmidt et al., 1888
- Species Biddulphia septemlocularis Kützing, 1844
- Species Biddulphia seticulosa Grunow, 1882
- Species Biddulphia setigera (J.W. Bailey) Mann, 1907 accepted as Triceratium setigerum J.W.Bailey, 1854
- Species Biddulphia seychellensis Grunow in Van Heurck, 1883
- Species Biddulphia seychellensis (Grunow in Van Heurck) F.W. Mills, 1883 accepted as Triceratium seychellense Grunow in Van Heurck, 1883
- Species Biddulphia shadboltiana (Greville) Mann, 1907 accepted as Triceratium shadboltianum f. shadboltianum Greville, 1862
- Species Biddulphia shulzei Boyer, 1898
- Species Biddulphia simplex Mereschkowsky, 1900
- Species Biddulphia sinensis Greville, 1866
- Species Biddulphia sinuata Greville, 1865
- Species Biddulphia smithii (Ralfs in Pritchard) Van Heurck, 1885 accepted as Ralfsiella smithii (Ralfs in Pritchard) P.A. Sims, D. M. Williams & Ashworth, 2018
- Species Biddulphia sparsepunctata Hajós in Hajós & Stradner, 1974
- Species Biddulphia spicata Boyer, 1922
- Species Biddulphia spinosa (J.W.Bailey) Boyer, 1927 accepted as Triceratium spinosum f. spinosum J.W. Bailey, 1844
- Species Biddulphia spinulosa (Grunow in Schmidt et al.) Mann, 1925 accepted as Triceratium spinulosum Grunow in Schmidt et al., 1885
- Species Biddulphia stipitata (J. E. Smith) Gray, 1821
- Species Biddulphia stokesiana (R.K.Greville) A.Mann, 1925 † accepted as Entogoniopsis stokesiana (R.K.Greville) J.Witkowski, P.A.Sims, N.I.Strelnikova & D.M.Williams, 2015 †
- Species Biddulphia striata Karsten, 1905
- Species Biddulphia striolata (Ehrenberg)
- Species Biddulphia sturtii Wise, 1952
- Species Biddulphia subaequa (Kützing) J.Ralfs, 1861
- Species Biddulphia subaequa Schmidt in Schmidt et al., 1888
- Species Biddulphia subjuncta Mann, 1907
- Species Biddulphia sublaevis Grunow in Van Heurck, 1882
- Species Biddulphia suborbicularis Grunow
- Species Biddulphia suborbiculata J.A.Long, D.P.Fuge & J.Smith, 1949 †
- Species Biddulphia subquadrata Boyer, 1922
- Species Biddulphia subrotundata (Schmidt in Schmidt et al.) Boyer, 1900 accepted as Triceratium subrotundatum f. subrotundatum Schmidt in Schmidt et al., 1886
- Species Biddulphia subsalsa Lemmermann, 1907
- Species Biddulphia surirella (Ehrenberg) Rabenhorst, 1864 accepted as Zygoceros surirella Ehrenberg, 1840
- Species Biddulphia suspecta M. Peragallo, 1924
- Species Biddulphia suzuensis Ichikawa in Ichikawa, Fuji & Bachmann, 1964
- Species Biddulphia szurdokpuespoekiensis Hajós, 1968
- Species Biddulphia tabellaria (Brightwell) Boyer, 1900 accepted as Triceratium tabellarium var. tabellarium Brightwell, 1856
- Species Biddulphia tabellariaeformis Forti, 1913
- Species Biddulphia tabellarium (T.Brightwell) C.S.Boyer, 1900 † accepted as Entogoniopsis tabellaria (T.Brightwell) J.Witkowski, P.A.Sims, N.I.Strelnikova & D.M.Williams, 2015
- Species Biddulphia tahitiensis Ricard, 1975
- Species Biddulphia temperei (Brun) Mann, 1925 accepted as Triceratium temperei Brun in Brun, Bergon et al., 1890
- Species Biddulphia tenera Strelnikova, 1974
- Species Biddulphia tenera Grove & Sturt, 1887
- Species Biddulphia tentaculifera Cleve, 1881
- Species Biddulphia tenuicornis Greville, 1865 † accepted as Parodontella tenuicornis (Greville) D. M. Williams & P.A. Sims in Sims et al., 2018 †
- Species Biddulphia tenuis L.W. Bailey, 1861
- Species Biddulphia tessellata (Greville) Boyer, 1900 accepted as Triceratium tessellatum Greville, 1861
- Species Biddulphia testudo (Brun in Brun & Tempère) Boyer, 1900 accepted as Tabulina testudo Brun in Brun & Tempère, 1889 †
- Species Biddulphia thumii (Schmidt in Schmidt et al.) Boyer, 1900 accepted as Cerataulus thumii Schmidt in Schmidt et al., 1888
- Species Biddulphia titiana Grunow in Van Heurck, 1883
- Species Biddulphia tortura Hendey & Sims, 1984
- Species Biddulphia translucida Van Heurck, 1909
- Species Biddulphia transversa Wigand, 1860
- Species Biddulphia tridens (Ehrenberg) Ehrenberg, 1841
- Species Biddulphia tridentata Ehrenberg
- Species Biddulphia tridentata ‘Weisse' according to Hustedt, 1930
- Species Biddulphia tridentata Weisse, 1854
- Species Biddulphia tridentula Ehrenberg, 1843
- Species Biddulphia triloba Sheshukova-Poretskaya V.S., 1967
- Species Biddulphia trilocularis Kützing, 1844
- Species Biddulphia trinacria L.W. Bailey, 1861
- Species Biddulphia tripartita (Grunow) Van Heurck
- Species Biddulphia tripos (Cleve) Mann, 1925 accepted as Triceratium tripos f. tripos Cleve, 1881
- Species Biddulphia trisinua Mann, 1925
- Species Biddulphia trisulca (J.W. Bailey ex Ralfs in Pritchard) Boyer, 1900 accepted as Triceratium trisulcum var. trisulcum J.W. Bailey ex Ralfs in Pritchard, 1861
- Species Biddulphia tschestnovii Pantocsek, 1892
- Species Biddulphia tubulosa Brun, 1891
- Species Biddulphia tumescens (Castracane) Mann, 1925 accepted as Triceratium tumescens Castracane, 1886
- Species Biddulphia tumida (Ehrenberg) Roper, 1859
- Species Biddulphia tuomeyi (J.W.Bailey) Roper, 1859
- Species Biddulphia turgida (Ehrenberg) W.Smith, 1856 accepted as Denticella turgida Ehrenberg, 1840
- Species Biddulphia turrigera Mann, 1925
- Species Biddulphia uncinata ‘Schmidt in Schmidt et al.' Mills, 1933
- Species Biddulphia undulata Long, Fuge & Smith, 1946
- Species Biddulphia undulosa Mann, 1925
- Species Biddulphia unifasciata Wigand, 1860
- Species Biddulphia ursina Ehrenberg, 1844
- Species Biddulphia vanheurckii
- Species Biddulphia varians (Lauder) Lebour, 1930 accepted as Bacteriastrum varians f. varians Lauder, 1864
- Species Biddulphia vasta Pantocsek, 1889
- Species Biddulphia venosa
- Species Biddulphia venulosa Barker & Meakin, 1949
- Species Biddulphia verrucosa Boyer, 1898
- Species Biddulphia vesiculosa (Agardh) Kützing, 1833 accepted as Diatoma vesiculosum Agardh, 1824
- Species Biddulphia virgata Grove & Sturt, 1886
- Species Biddulphia vitrea Brun, 1891
- Species Biddulphia vittata Grove & Sturt, 1887
- Species Biddulphia voigtii Meister, 1932
- Species Biddulphia weissei (Grunow in Schmidt et al.) E. Jørgensen, 1905 accepted as Triceratium weissii Grunow in A.Schmidt, 1886 †
- Species Biddulphia weissflogii Grunow, 1882
- Species Biddulphia weissflogii Janisch in Schmidt et al., 1888
- Species Biddulphia weissii (Grunow in Schmidt et al.) Van Heurck, 1909 accepted as Triceratium weissii Grunow in A.Schmidt, 1886 †
- Species Biddulphia woolmanii Kain & Schultze, 1889
- Species Biddulphia zanzibarica A. Schmidt, 1894
- Genus Biddulphiopsis H.A. von Stosch & R. Simonsen, 1984
- Genus Donskinica Strelnikova & Kozyrenko †
- Genus Euodiella P.A. Sims, 2000 †
- Genus Fenneria J.Witkowski, 2018 †
- Genus Hydrosera G.C. Wallich, 1858 (2)
- Genus Isthmia C.A. Agardh, 1832 (5)
- Genus Medlinia P.A.Sims, 1998 †
- Genus Neohuttonia O. Kuntze, 1898
- Genus Pseudotriceratium A. Grunow, 1884
- Genus Stoermeria J.P. Kociolek, L. Escobar & S. Richardson, 1996
- Genus Terpsinoë C.G. Ehrenberg, 1843 (4)
- Genus Trigonium P.T. Cleve, 1867 (2)
- Genus Crawfordia P.A.Sims, J.Witkowski & E.A.César †
- Genus Entogoniopsis P.A.Sims, N.I.Strelnikova, J.Witkowski & D.M.Williams, 2015 (1)
- Genus Trilamina P.A.Sims, J.Witkowski, N.I.Strelnikova & D.M.Williams, 2015 †
- Order Hemiaulales (17)
- Order Triceratiales (168)
- Superorder Chaetocerotanae (95)
- Superorder Corethranae (1)
- Superorder Coscinodiscanae (300)
- Superorder Cymatosirophycanae (10)
- Superorder Lithodesmiophycanae (7)
- Superorder Rhizosolenianae (37)
- Superorder Thalassiosiranae (192)
- Order Arcanodiscales (5)
- Order Stictocyclales
- Subclass Fragilariophycidae (483)
- Order Centrales
