Article · Wikipedia archive · Last revised Jun 10, 2026

Bacillariophyceae

Bacillariophyceae is a class of diatoms. Previously, this class was equivalent to Diatomeae, the taxonomic name for all diatoms. However, due to both the known and estimated diversity of diatoms, since 2019 they have been expanded to several classes. In particular, Bacillariophyceae was given the following modified diagnosis:"Chain-forming, colonial or solitary; valve outline almost always bipolar; valve pattern organized bilaterally about an elongate axial rib (sternum), as in a feather; valve structure simple or chambered; rimoportulae generally only one or two per valve or none, sometimes accompanied by special slits involved in motility; sexual reproduction involving gametangiogamy and almost always with gametes of equal size ; perizonium generally differentiated into two distinct series, transverse and longitudinal; chloroplasts usually only one, two or a few and large, less often many and small."

Last revised
Jun 10, 2026
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≈ 2 min
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Citations
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Wikipedia ↗
Bacillariophyceae
Temporal range:
Bacillaria paxillifera
Scientific classification Edit this classification
Domain: Eukaryota
Clade: Sar
Clade: Stramenopiles
Division: Ochrophyta
Clade: Bacillariophyta
Class: Bacillariophyceae
Haeckel 1878, emend. Adl et al. 20191
Subclasses and families12
  • Urneidophycidae
  • Fragilariophycidae
  • Bacillariophycidae
  • Striatellaceae

Bacillariophyceae is a class of diatoms.1 Previously, this class was equivalent to Diatomeae, the taxonomic name for all diatoms.3 However, due to both the known and estimated diversity of diatoms, since 2019 they have been expanded to several classes.4 In particular, Bacillariophyceae was given the following modified diagnosis:1

"Chain-forming, colonial or solitary; valve outline almost always bipolar; valve pattern organized bilaterally about an elongate axial rib (sternum), as in a feather; valve structure simple or chambered; rimoportulae generally only one or two per valve or none, sometimes accompanied (or replaced?) by special slits (the 'raphe') involved in motility; sexual reproduction involving gametangiogamy and almost always with gametes of equal size (although sometimes with behavioral differentiation and/or morphological differences); perizonium generally differentiated into two distinct series, transverse and longitudinal; chloroplasts usually only one, two or a few and large, less often many and small."

References

References

  1. Adl, Sina M.; Bass, David; Lane, Christopher E.; Lukeš, Julius; Schoch, Conrad L.; Smirnov, Alexey; Agatha, Sabine; Berney, Cedric; Brown, Matthew W.; Burki, Fabien; Cárdenas, Paco; Čepička, Ivan; Chistyakova, Lyudmila; Del Campo, Javier; Dunthorn, Micah; Edvardsen, Bente; Eglit, Yana; Guillou, Laure; Hampl, Vladimír; Heiss, Aaron A.; Hoppenrath, Mona; James, Timothy Y.; Karnkowska, Anna; Karpov, Sergey; Kim, Eunsoo; Kolisko, Martin; Kudryavtsev, Alexander; Lahr, Daniel J.G.; Lara, Enrique; Le Gall, Line (26 September 2018). "Revisions to the Classification, Nomenclature, and Diversity of Eukaryotes". The Journal of Eukaryotic Microbiology. 66 (1): 4–119. doi:10.1111/JEU.12691. PMC 6492006. PMID 30257078.
  2. "AlgaeBase :: Listing the World's Algae". www.algaebase.org. Archived from the original on 2025-08-05. Retrieved 2025-08-27.
  3. Cavalier-Smith, Thomas (5 September 2017). "Kingdom Chromista and its eight phyla: a new synthesis emphasising periplastid protein targeting, cytoskeletal and periplastid evolution, and ancient divergences". Protoplasma. 255 (1): 297–357. doi:10.1007/s00709-017-1147-3. PMC 5756292. PMID 28875267.
  4. Friedl, Thomas (2024), Büdel, Burkhard; Friedl, Thomas; Beyschlag, Wolfram (eds.), "Algae from Secondary Endosymbiosis", Biology of Algae, Lichens and Bryophytes, Berlin, Heidelberg: Springer, pp. 219–383, doi:10.1007/978-3-662-65712-6_5, ISBN 978-3-662-65712-6, retrieved 2025-10-17{{citation}}: CS1 maint: work parameter with ISBN (link)