prokaryotes - bacteria see Domain Bacteria Woese et al. 1990
   Domain "Archaea" Woese et al. 1990
     Phylum "Euryarchaeota" Garrity and Holt 2001
       Class Thermoplasmata Reysenbach 2002 [monotypic]
         Order Thermoplasmatales Reysenbach 2002
           1 Family Cuniculiplasmataceae Golyshina et al. 2016 [monotypic]
           2 Family Ferroplasmaceae Golyshina et al. 2000
           3 Family Picrophilaceae Schleper et al. 1996 [monotypic]
           4 Family Thermoplasmataceae Reysenbach 2002 [monotypic]
           5 Genus Thermogymnomonas Itoh et al. 2007, incertae sedis