Raphidiopsis raciborskii

Raphidiopsis raciborskii is a freshwater cyanobacterium.

This bacterium is an aquatic photosynthetic bacteria belonging to the phylum Cyanobacteria. They are composed of chained filaments known as trichomes that can show variation in morphology, varying from about 50–300 micrometers in length. These bacteria can also produce a thick walled, cylindrical, spore like structure known as akinetes, which also demonstrate variation in morphology. Some strains of this species are able to produce several toxins which affect humans: cylindrospermopsin, anatoxin-a and saxitoxin. This first toxin, cylindrospermopsin, has the ability to affect the liver and kidneys in humans as well as cause mild skin reactions upon exposure. The last two toxins, anatoxin-a and saxitoxin, are thought to be shellfish neurotoxins. Research has shown that C. raciborskii can naturally produce butylated hydroxytoluene, an antioxidant, food additive, and industrial chemical.