The cyanobaterial genus Phormidesmis.

Characteristics and detailed morphology of the genus Characterization and detailed morphology of the genus Phormidesmis TURICCHIA et al. 2009 are presented. This genus is more related to thin cyanobacteria of the family Pseudanabaenaceae than to the genus Phormidium sensu stricto, which is confirmed by ultrastructural analysis, showing mainly parietal arrangement of thylakoids. Other potential and similar morphotypes from the genus Phormidium are discussed.