oxyphototroph prokaryotes - bacteria see Domain Bacteria Woese et al. 1990 stat. inval.
   Class Cyanoprokaryota Komárek & Golubić 1990 nom. nud. - cyanoprokaryotes
     Order Chroococcales Ardissone (1887) see Order Chroococcales corrig. Ardissone 1887
       Family Hydrococcaceae Kützing (1843) see Family Hydrococcaceae Kützing 1843
         Form genus Hydrococcus Kütz. (1833), nom. cons. prop. see Genus Hydrococcus Kützing 1833 nom. cons.