Scytonema

Scytonema
Scientific classification
Domain:	Bacteria
Phylum:	Cyanobacteria
Class:	Cyanophyceae
Order:	(Hormogonales)
Family:	Scytonemataceae
Genus:	Scytonema Agardh ex Bornet et Flahault

Scytonema is a genus of photosynthetic cyanobacteria that contains over 100 species. It grows in filaments that form dark mats. Many species are aquatic and are either free-floating or grow attached to a submerged substrate, while others species grow on terrestrial rocks, wood, soil, or plants. Scytonema is a nitrogen fixer, and can provide fixed nitrogen to the leaves of plants on which it is growing. Some species of Scytonema form a symbiotic relationship with fungi to produce a lichen.

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