Home / Chlorophyceae / Unicells / Non-flagellated / Nannochloris

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Name derivation:

Little green thing (nano- small, -chloris green).  [Seems to me that the name should be Nanochloris...]



Nannochloris  Naumann  1921;  2 of 8 species descriptions are currently accepted taxonomically (Guiry and Guiry 2013).

Order Chlorellales;  Family Chlorellaceae



Subpherical to subcylindrical Unicells 0.8 – 4.5 µm in diameter.  May occur in pairs enclosed in mucilage, or often in large numbers in a mucilage mass (Schubert 2003).


Similar genera:

Similar to Nannochloropsis (Eustigmatophyceae) morphologically, as well as to several genera of greens (Henley et al. 2004).  Easily confused with small cyanobacteria (Schubert 2003).


Optimal temperature:

Nannochloris has optimal growth at ~30 – 35 C.


Plankton and benthos of a wide trophic variety of lakes.  Apparently also in brackish and marine systems.  Because of their size (~2 µm) they are on the border between picoplankton and nanoplankton, thus have a competitive advantage over larger phytoplankton when nutrients are limited (large surface area to volume ratio).  Easily grazed by micro-zooplankton (flagellates and ciliates), they form a link to the classical food web, along with bacteria in the microbial food web or loop (Wehr and Sheath 2003).



Guiry, M.D. and G.M. Guiry  2013.  AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 15 October 2012.

Henley, W.J., J.L. Hironaka, L. Guillou, M.A. Buchheim, J.A. Bucheim, M.W. Fawley, and K.P. Fawley  2004.  Phylogenetic analysis of the ‘Nannochloris-like’ algae and diagnoses of Picochlorum oklahomensis gen. et sp. nov. (Trebouxiophyceae, Chlorophyta)

Schubert, L.E.  2003.Nonmotile coccoid and colonial green algae.    In:  Freshwater Algae of North America, Wehr, J.D., and R.G. Sheath (Eds).  Academic Press.  Chapter 7.