Picocystis is a monotypic genus of green algae, the sole species is Picocystis salinarum.[1] It is placed within its own class, Picocystophyceae in the division Chlorophyta.[2]

Picocystis
Picocystis salinarum
Scientific classification Edit this classification
Clade: Viridiplantae
Division: Chlorophyta
Class: Picocystophyceae
Eikrem & Lopes dos Santos
Order: Picocystales
Eikrem & Lopes dos Santos
Family: Picocystaceae
Eikrem & Lopes dos Santos
Genus: Picocystis
R.A.Lewin 2001 emend. Eikrem & Lopes dos Santos 2017
Species:
P. salinarum
Binomial name
Picocystis salinarum
R.A.Lewin 2001

Structure

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Picocystis salinarum cells under normal conditions have a spherical or oval shape. Their size ranges from 2 to 3μm (micrometer, 10^-6) in diameter. Under conditions of nutrient depletion they appear to form a trillobe shape. This trillobe shape gives it the nickname Mickey Mouse, due to its appearance to the famous character's head. The general appearance resembles that of a standard green algae.

The pigments are composed mainly from chlorophyll a and b and the carotenoids violaxanthin, alloxanthin, monadoxanthin, neoxanthin, lutein, diatoxanthin and zeaxanthin.[3][4]

The cell wall is mainly composed of polymers of the monosaccharide arabinose, polyarabinose.[3]

Habitat

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The species have been found in saline or hypersaline alkaline environments.[5][6]

 
Picocystis is one of the smallest green algae. Picocystis salinarum occurs in vast numbers in Mono Lake, where it is also referred to as Mickey Mouse (see bottom left).

References

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  1. ^ Guiry, M.D.; Guiry, G.M. "Picocystis". AlgaeBase. World-wide electronic publication, National University of Ireland, Galway.
  2. ^ Lopes Dos Santos A, Pollina T, Gourvil P, Corre E, Marie D, Garrido JL, Rodríguez F, Noël MH, Vaulot D, Eikrem W (October 2017). "Chloropicophyceae, a new class of picophytoplanktonic prasinophytes". Scientific Reports. 7 (1): 14019. Bibcode:2017NatSR...714019L. doi:10.1038/s41598-017-12412-5. PMC 5656628. PMID 29070840.
  3. ^ a b Lewin RA, Krienitz L, Goericke R, Takeda H, Hepperle D (2000). "Picocystis salinarum gen. et sp nov (Chlorophyta) - a new picoplanktonic green alga". Phycologia. 39 (6): 560–565. doi:10.2216/i0031-8884-39-6-560.1. S2CID 83584521.
  4. ^ Lopes Dos Santos A, Gourvil P, Rodríguez F, Garrido JL, Vaulot D (February 2016). "Photosynthetic pigments of oceanic Chlorophyta belonging to prasinophytes clade VII". Journal of Phycology. 52 (1): 148–55. doi:10.1111/jpy.12376. hdl:10261/129034. PMID 26987097. S2CID 3160723.
  5. ^ Krienitz L, Bock C, Kotut K, Luo W (January 2012). "Picocystis salinarum (Chlorophyta) in saline lakes and hot springs of East Africa". Phycologia. 51 (1): 22–32. doi:10.2216/11-28.1. S2CID 84149071.
  6. ^ Stamps BW, Nunn HS, Petryshyn VA, Oremland RS, Miller LG, Rosen MR, et al. (November 2018). "Metabolic Capability and Phylogenetic Diversity of Mono Lake during a Bloom of the Eukaryotic Phototroph Picocystis sp. Strain ML". Applied and Environmental Microbiology. 84 (21). doi:10.1128/AEM.01171-18. PMC 6193381. PMID 30120120.