Editing Diatom (section)

===Genera and species===
An estimated 20,000 [[Extant taxon|extant]] diatom [[species]] are believed to exist, of which around 12,000 have been named to date according to Guiry, 2012<ref>{{cite journal |doi=10.1111/j.1529-8817.2012.01222.x|title=How many species of algae are there? |journal=Journal of Phycology |volume=48 |issue=5 |pages=1057–1063 |year=2012 |last1=Guiry |first1=M. D. |pmid=27011267|bibcode=2012JPcgy..48.1057G |s2cid= 30911529}}</ref> (other sources give a wider range of estimates<ref name="HasleSyvertsen1996">{{cite book|first1=Grethe R. |last1=Hasle|first2=Erik E. |last2=Syvertsen|first3=Karen A. |last3=Steidinger|first4=Karl |last4=Tangen|editor-first=Carmelo R. |editor-last=Tomas|title=Identifying Marine Diatoms and Dinoflagellates|chapter-url=https://books.google.com/books?id=KQxPtwonlqoC|access-date=13 November 2013|date=25 January 1996|publisher=Academic Press|isbn=978-0-08-053441-1|pages=5–385|chapter=Marine Diatoms|archive-date=3 January 2014|archive-url=https://web.archive.org/web/20140103085057/http://books.google.com/books?id=KQxPtwonlqoC|url-status=live}}</ref><ref name="RoundCrawford1990">{{cite book|first1=Frank Eric |last1=Round|first2=R. M. |last2=Crawford|first3=D. G. |last3=Mann|title=The Diatoms: Biology & Morphology of the Genera|url=https://books.google.com/books?id=xhLJvNa3hw0C|access-date=13 November 2013|year=1990|publisher=Cambridge University Press|isbn=978-0-521-36318-1|archive-date=24 May 2021|archive-url=https://web.archive.org/web/20210524082251/https://books.google.com/books?id=xhLJvNa3hw0C|url-status=live}}{{page needed|date=March 2017}}</ref><ref name="Lund95">Canter-Lund, H. and Lund, J. W. G. (1995). ''Freshwater Algae: Their microscopic world explained'', Biopress Limited. {{ISBN|0-948737-25-5}}.{{page needed|date=March 2017}}</ref><ref>{{cite journal |doi=10.1007/BF00940439 |jstor=23675282 |title=The species concept in diatoms: Evidence for morphologically distinct, sympatric gamodemes in four epipelic species |journal=Plant Systematics and Evolution |volume=164 |issue=1/4 |pages=215–37 |year=2005 |last1=Mann |first1=David G. |s2cid=37684109 }}</ref>). Around 1,000–1,300 diatom genera have been described, both extant and fossil,<ref>{{cite journal |doi= 10.1080/0269249X.1999.9705462|title=Catalogue of the Diatom Genera |journal=Diatom Research |volume=14 |issue=1 |pages=1–190 |year=1999 |last1=Fourtanier |first1=Elisabeth |last2=Kociolek |first2=J. Patrick|bibcode=1999DiaRe..14....1F }}</ref><ref>The [[World Register of Marine Species]] lists 1,356 diatom genus names from all habitats as at July 2020, of which 1,248 are "accepted".</ref> of which some 250–300 exist only as fossils.<ref>Queries to the World Register of Marine Species, July 2020, return 299 "fossil only" genus names, of which 285 are "accepted".</ref>