picochlorum eukaryotum picochlorum eukaryotum picochlorum eukaryotum, also called nanochlorum eukaryotum, is a species of marine coccoidal green algae. picochlorum eukaryotum scientific classification (unranked): viridiplantae division: chlorophyta class: trebouxiophyceae order: chlorellales family: incertae sedis genus: picochlorum species: p. eukaryotum binomial name picochlorum eukaryotumw.j.henley, j.l.hironaka, l.guillou, m.a.buchheim, j.a.buchheim, m.w.fawley & k.p.fawley synonyms nanochlorum eukaryotum this alga is approximately 1.5 microns in size. initial research showed it to be related to chlorella vulgaris.