Procaryotic Genera
   Domain "Archaea" Woese et al. 1990
     Phylum Crenarchaeota Garrity and Holt 2001 [monotypic]
       Class Thermoprotei Reysenbach 2001 see Class Thermoprotei Reysenbach 2002
         Order Desulfurococcales Huber and Stetter 2001 nom. inval. see Order Desulfurococcales Huber and Stetter 2002
           1 Family Desulfurococcaceae Zillig and Stetter 1983
           2 Family Pyrodictiaceae Burggraf et al. 1997