[Photo from Roscoff Culture Collection – Roscoff, France]
Micromonas pusilla (AlgaeBase) is a species in Micromonas, a genus of green algae in the family Mamiellaceae. Micromonas is a group of small unicellular pear-shaped micro-algae that do not have a cell wall. Just like other members in the class, they have a single mitochondrion and a single chloroplast, which covers almost half of the cell. They are able to swim due to the presence of a scale-less flagellum.
Before the characterization in 2016 of a second species, Micromonas commoda, Micromonas pusilla was considered to be the only species in the genus. It is suggested to be the dominant photosynthetic picoeukaryote in some marine ecosystems. Unlike many marine algae, it is distributed widely in both warm and cold waters. It is a strong swimmer and exhibits a phototaxic response. M. pusilla is divided into 3 to 5 different clades despite their similarity in morphologies and habitats. Varying ratios of clades contribute to the M. pusilla population throughout the marine ecosystem leading to the hypothesis of clades arising based on niche occupation and susceptibility to virus infection. [From Wikipedia]
The experimental samples used for this species can be found in Data S9 of our supplementary data.