living organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Superkingdom Prokaryotae see Superkingdom Prokarya
     Kingdom Monera Haeckel 1866 see Domain Bacteria Woese et al. 1990
       Division Cyanophycota see Phylum Cyanobacteria (ex Stanier 1974) Cavalier-Smith 2002
         Class Cyanophyceae Schaffner (1909) see Class Cyanobacteria Cavalier-Smith, 2002
           Order Nostocales Borzì (1914)
             Family Scytonemataceae F.T. Kützing ex O. Kirchner in A. Engl. & H. Prantl (1898)
               1 Genus Scytonema C.Agardh ex Bornet & Flahault (1887)
               2 Genus Tolypothrix F.T. Kützing ex É. Bornet & C. Flahault 1886-1888[1887] [ICBN]
               3 Genus Plectonema Thuret ex Gomont (1892)