In this section
Densely united, heteropolar cyanobacterial filaments, forming mounds attached to surfaces. Filaments have heterocytes at their bases against the substrate and taper to long hair-like cells at the tips. Akinetes are lacking (cf. Gloeotrichia). False branching absent; filaments divide by development of an intercalary heterocyte, which dissociates from the parent filament and remains parallel to it within the colony. Organelles are absent from the cells.