prokaryotes - bacteria see Domain Bacteria Woese et al. 1990 Domain "Archaea" Woese et al. 1990 Phylum "Crenarchaeota" Garrity and Holt 2001 [monotypic] Class Thermoprotei Reysenbach 2002 Order Acidilobales Prokofeva et al. 2009 1 Family Acidilobaceae Prokofeva et al. 2009 [monotypic] 2 Family Caldisphaeraceae Prokofeva et al. 2009 [monotypic]