Phylum Cyanobacteria Garcia-Pichel et al. (2020) see Phylum Cyanobacteriota Oren et al. 2022
   Class Cyanophyceae Hauck (1885) see Class Chroococcophyceae Hollerbach et al. 1953
     Order Synechococcales Hoffmann, Komárek & Kaštovský (2005), nom. inval. see Order Synechococcales Hoffmann et al. 2005 nom. nud.
       Family Prochlorococcaceae Komárek & Strunecký (2020) see Family Prochlorococcaceae Komárek and Strunecký 2020
         Genus Cyanobium Rippka & Cohen-Baz. (1983), nom. inval. see Genus Cyanobium Rippka and Cohen-Bazire 1983 nom. inval.