Diagnostic features
Blue-green isopolar cyanobacterial filaments encased in a yellow-brown mucilage sheath. False branching is characteristically at right-angle bends, either forming a loop (prior to division) or two parallel branches at right angles to the original filament. Heterocytes cylindrical to barrel-shaped, intercalary, located throughout the filaments. Organelles absent from the cells, but granules/vesicles common.
![[Scytonema] tuft, X10. Photo: Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/scytonema10X__ScaleWidthWzEwMjRd.jpg)
![[Scytonema], Lee Stream, X320. Photo: Otago Regional Council & Manaaki Whenua Image](/assets/Tools-And-Resources/Identification/algae/scytonema320lee__ScaleWidthWzEwMjRd.jpg)