nostoc commune var. sphaeroides nostoc commune var. sphaeroides nostoc commune var. sphaeroides is an edible cyanobacterium found in diverse habitats such as lakes and rivers. it is used as a food and nutritional supplement and has reputed pharmaceutical properties. nostoc commune var. sphaeroides scientific classification domain: bacteria phylum: cyanobacteria class: cyanophyceae order: nostocales family: nostocaceae genus: nostoc species: n. commune variety: n. c. var. sphaeroides trinomial name nostoc commune var. sphaeroideskutzing