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 Parasynechococcus Coutinho, Tschoeke, Thompson & Thompson (2020) see Genus Parasynechococcus Coutinho et al. 2020