Microcystis robusta is a type of cyanobacteria characterized by spherical cells that cluster into colonies. These colonies vary in size and shape, often appearing as irregular masses. Each cell is relatively small, typically measuring between 3 and 8 micrometers in diameter, and is surrounded by a mucilaginous sheath that gives the colony a slimy texture. Commonly found in freshwater environments like lakes, ponds, and slow-moving rivers, Microcystis robusta is known for its rapid proliferation under favorable conditions, forming blooms. While crucial to aquatic ecosystems, this species can produce toxins harmful to other organisms and potentially pose health risks to humans during bloom events.