prokaryotes - bacteria see Domain Bacteria Woese et al. 1990 Domain "Bacteria" Woese et al. 1990 Phylum "Thermotogae" Reysenbach 2001 [monotypic] Class Thermotogae Reysenbach 2002 1 Order Kosmotogales Bhandari and Gupta 2014 [monotypic] 2 Order Mesoaciditogales Itoh et al. 2016 [monotypic] 3 Order Petrotogales Bhandari and Gupta 2014 [monotypic] 4 Order Thermotogales Reysenbach 2002 [monotypic]