Home / Chlorophyceae / Unicells / Flagellated / Tetraselmis
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Name derivation:
Classification:
Tetraselmis F.Stein 1878; 30 of 34 species descriptions are currently considered acceptable (Guiry and Guiry 2013). Order Chlorodendrales; Family Chlorodendraceae
Morphology:
Tetraflagellate green unicells, flagella in opposite pairs, oval, somewhat flattened, 10 to 15 µm long. Individual cells have a single lobate chloroplast (rarely two) containing a pyrenoid. Usually green, but can accumulate haematochrome, probably in bright sunlight, turning more red.
Similar genera:
Apparently Tetraselmis is the motile stage of the now-retired (as of 1980) genus Prasinocladus, an attached phase lacking flagella. Now both stages are known as Tetraselmis. Scherffelia, not separated from Tetraselmis in PhycoKey, is described as lacking pyrenoids but otherwise similar.
Commercial use:
High lipid content is valuable in aquaculture. Methane production in lipid-free (pre-extracted) Tetraselmis is higher in lysed cells, and this can be achieved in anaerobic digestion (Ward and Lewis 2015). Production of antioxidants. Nutrient stress such as growth in low or no P-source diminishes production of both phenolics and carotenoids in Tetraselmis suecica, as well as in Chlorella vulgaris and in the diatom Phaeodactylum tricornutum (Goiris et al. 2015).
Habitat:
Mostly free-living marine plankton with some freshwater species. Also found as an endosymbiont in the marine acoelomate flat (but not a platyhelminth ‘flatworm’) worm Symsagittifera roscoffensis (‘mint sauce worms’) common in European shallow coastal waters.
References:
Goiris, K., W. Van Colen, I. Wilches, F. Leon-Tamariz, L. De Cooman and K. Muylaert 2015. Impact of nutrient stress on antioxidant production in three species of microalgae. Algal Research 7:51-57. Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 22 May 2013. Stein, F. von 1878. Der Organismus der Infusionsthiere. III. Flagellaten I. pp. 1-154. Leipzig: Engelmann. Ward, A., and D. Lewis 2015. Pre-treatment options for halophytic microalgae and associated methane production. Bioresource Technology 177:410-413.