Scytonema

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Scytonema A genus of filamentous cyanobacteria (section IV), in which the filaments do not taper, and show frequent false branching owing to a loop of trichome breaking through the sheath and then rupturing. The filaments have distinct basal and apical regions and form erect tufts, on wet rocks, soil, etc. The genus now includes organisms formerly included in the genus Tolypothrix.