Plant of the Month — September 2020

Microcystis aeruginosa (Kütz.) Kütz.

Find out more about Microcystis aeruginosa (Kütz.) Kütz.

Or ‘not quite’ Plant of the Month. For September we have two photosynthetic organisms that lie at opposite ends of evolution. On the left is Microcystis aeruginosa, a cyanobacterium (or blue-green alga) that often forms blooms in freshwater lakes. This species is toxic and has been implicated in the deaths of animals that drink from the water. On the right is the dinoflagellate Ceratium hirundinella, a single-celled protist that is mixotrophic, meaning that it can gain energy by ingesting prey items, but is also photosynthetic as it has incorporated functional chloroplasts from other organisms.

The photosynthetic cyanobacteria were the ancestors of chloroplasts (the site of photosynthesis in all plants); in evolutionary history they were ingested by a non-photosynthetic organism and retained, essentially turning an animal into a plant.

The photo was taken under the microscope of a single drop of water, collected from Herdsman Lake. The scale bar is equivalent to 50 µm, which equals 0.05 millimetres (or 5 hundredths of a millimetre).

Photo: J. Huisman

Find out more about Microcystis aeruginosa (Kütz.) Kütz.

Are you sure you want to delete this Plant of the Month entry?