Editing Cryptomonad (section)

==Classification==
[[File:CSIRO ScienceImage 6743 SEM Cryptophyte.jpg|thumb|Cryptophytes under [[Scanning electron microscope|SEM]]]]
[[File:CSIRO ScienceImage 7234 microalgal cultures.jpg|thumb|Cryptophytes under [[light microscope]] ]]
{{further|Wikispecies:Cryptophyceae}}

The first mention of cryptomonads appears to have been made by [[Christian Gottfried Ehrenberg]] in 1831,<ref>{{cite journal |last=Novarino |first=G. |date=2012 |title=Cryptomonad taxonomy in the 21st century: The first 200 years |journal=Phycological Reports: Current Advances in Algal Taxonomy and Its Applications: Phylogenetic, Ecological and Applied Perspective |pages=19–52 |url= https://www.researchgate.net/publication/265520014 |access-date=2018-10-16}}</ref> while studying [[Infusoria]]. Later, botanists treated them as a separate [[algae]] group, class Cryptophyceae or division Cryptophyta, while zoologists treated them as the [[flagellate]] [[protozoa]] order Cryptomonadina. In some classifications, the cryptomonads were considered close relatives of the [[dinoflagellate]]s because of their (seemingly) similar pigmentation, being grouped as the [[Pyrrhophyta]]. Cryptomonad chloroplasts are closely related to those of the [[heterokont]]s and [[haptophyte]]s, and the three groups were united by Cavalier-Smith as the [[Chromista]]. However, the case that the organisms themselves are closely related was counter-indicated by the major differences in cell organization ([[ultrastructural identity]]), suggesting that the three major lineages assigned to the chromists had acquired plastids independently, and that chromists are polyphyletic. The perspective that cryptomonads are primitively heterotrophic and secondarily acquired chloroplasts, is supported by molecular evidence.<ref>{{cite journal|pmid=30482201|pmc=6260743 |date=2018 |last1=Cenci |first1=U. |last2=Sibbald |first2=S. J. |last3=Curtis |first3=B. A. |last4=Kamikawa |first4=R. |last5=Eme |first5=L. |last6=Moog |first6=D. |last7=Henrissat |first7=B. |last8=Maréchal |first8=E. |last9=Chabi |first9=M. |last10=Djemiel |first10=C. |last11=Roger |first11=A. J. |last12=Kim |first12=E. |last13=Archibald |first13=J. M. |title=Nuclear genome sequence of the plastid-lacking cryptomonad Goniomonas avonlea provides insights into the evolution of secondary plastids |journal=BMC Biology |volume=16 |issue=1 |page=137 |doi=10.1186/s12915-018-0593-5 |doi-access=free }}</ref>   Parfrey et al. and Burki et al. placed Cryptophyceae as a sister clade to the [[Green algae|Green Algae]],<ref>{{cite journal|author-link1=Laura Wegener Parfrey|last1=Parfrey|first1=Laura Wegener|last2=Lahr|first2=Daniel J. G.|last3=Knoll|first3=Andrew H.|last4=Katz|first4=Laura A.|author-link4=Laura A. Katz|title=Estimating the timing of early eukaryotic diversification with multigene molecular clocks|journal=Proceedings of the National Academy of Sciences of the United States of America|date=August 16, 2011|volume=108|issue=33|pages=13624&ndash;13629|doi=10.1073/pnas.1110633108|pmid=21810989|pmc=3158185|bibcode=2011PNAS..10813624P |doi-access=free}}</ref> or green algae plus [[glaucophytes]].<ref>{{Cite journal|last1=Burki|first1=Fabien|last2=Kaplan|first2=Maia|last3=Tikhonenkov|first3=Denis V.|last4=Zlatogursky|first4=Vasily|last5=Minh|first5=Bui Quang|last6=Radaykina|first6=Liudmila V.|last7=Smirnov|first7=Alexey|last8=Mylnikov|first8=Alexander P.|last9=Keeling|first9=Patrick J. |date=2016-01-27 |title=Untangling the early diversification of eukaryotes: a phylogenomic study of the evolutionary origins of Centrohelida, Haptophyta and Cryptista |journal=Proc. R. Soc. B |language=en |volume=283 |issue=1823 |pages=20152802 |doi=10.1098/rspb.2015.2802 |issn=0962-8452 |pmid=26817772 |pmc=4795036}}</ref>  The sister group to the cryptomonads is likely the kathablepharids (also referred to as katablepharids), a group of flagellates that also have ejectisomes.<ref>{{cite journal|doi=10.3389/fevo.2020.00140 |doi-access=free |title=Mitochondrial Genomes of Hemiarma marina and Leucocryptos marina Revised the Evolution of Cytochrome c Maturation in Cryptista |date=2020 |last1=Nishimura |first1=Yuki |last2=Kume |first2=Keitaro |last3=Sonehara |first3=Keito |last4=Tanifuji |first4=Goro |last5=Shiratori |first5=Takashi |last6=Ishida |first6=Ken-Ichiro |last7=Hashimoto |first7=Tetsuo |last8=Inagaki |first8=Yuji |last9=Ohkuma |first9=Moriya |journal=Frontiers in Ecology and Evolution |volume=8 }}</ref>

One suggested grouping is as follows: (1) ''[[Cryptomonas]]'', (2) ''[[Chroomonas]]/[[Komma caudata|Komma]]'' and ''[[Hemiselmis]]'', (3) ''[[Rhodomonas]]/[[Rhinomonas]]/[[Storeatula]]'', (4) ''[[Guillardia]]/[[Hanusia]]'', (5) ''[[Geminigera]]/[[Plagioselmis]]/[[Teleaulax]]'', (6) ''[[Proteomonas sulcata]]'', (7) ''[[Falcomonas daucoides]]''.<ref name="urlCryptomonads">{{cite web |url=http://tolweb.org/Cryptomonads/2396 |title=Cryptomonads |access-date=2009-06-24}}</ref>