Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Domain Bacteria Woese et al. 1990 [paraphyletic?]
             Superphylum Terrabacteria Battistuzzi et al. 2004
               Phylum Cyanobacteria (ex Stanier 1974) Cavalier-Smith 2002 - cyanobacteria
                 Class "Cyanobacteria" Cavalier-Smith, 2002
                   Subclass Nostocophycideae
                     Order Nostocalesᵀ Borzì (1914)
                       Family Hapalosiphonaceae Elenkin (1917), nom. cons.
                         01 Genus Albrightia Copel. (1936) [monotypic]
                         02 Genus Baradlaia P. Palik (1960) [monotypic]
                         03 Genus Brachytrichiopsis Jao (1944)
                         04 Genus Chondrogloea W. Schmidle in Engl. (1901)
                         05 Genus Fischerella (E. Bornet & C. Flahault) M. Gomont (1895)
                         06 Genus Fischerellopsis Fritsch (1932)
                         07 Genus Hapalosiphonᵀ C. Nägeli in F.T. Kützing ex Bornet & Flahault 1886-1888[1887]
                         08 Genus Leptopogon Borzi (1906)
                         09 Genus Loefgrenia Gomont in Wittrock et al. (1896)
                         10 Genus Mastigocladus F.J. Cohn ex O. Kirchner in A. Engl. & H. Prantl (1898)
                         11 Genus Mastigocoleopsis Geitler (1925)
                         12 Genus Mastigocoleus G. Lagerheim ex Bornet & Flahault 1886-1888[1887]
                         13 Genus Matteia A. Borzì (1907)
                         14 Genus Nostochopsis Wood ex Bornet & Flahault 1886 [ICBN]
                         15 Genus Parthasarathiella N. Subba Raju (1962)
                         16 Genus Thalpophila Borzì (1907)
                         17 Genus Westiella Borzì (1907)
                         18 Genus Westiellopsis Janet (1941)