Micromonas is a motile unicell with a single chloroplast and mitochondrion and no scales on its cell surface. Micromonas pusilla was the first picoplanktonic species to be described and has been revealed as the dominating species within the picoplankton communities in coastal and open-oceanic regions. The species was originally named Chromulina pusilla Butcher, and was renamed later on. Currently, all Micromonas strains are assigned to this single species within the genus Micromonas. However, M. pusilla strains fall into distinct phylogenetic clades and therefore it is likely that the designation M. pusilla harbours several different (cryptic) species.

Publication:
Verhelst, B. et al. The complex intron landscape and massive intron invasion in a picoeukaryote provides insights into intron evolution. Genome Biol Evol. 5, 2393-401 (2013).