Procaryotic Genera Count: [*] 25p;39c;84o;215f;1008g [28 May 2016] Domain "Archaea" Woese et al. 1990 Count: [*] 2p;8c;12o;21f;73g [26 May 2016] Phylum Euryarchaeota Garrity and Holt 2001 Count: [*] 7c;9o;16f;50g [26 May 2016] Class Methanococci Boone 2001 nom. inval. see Class Methanococci Boone 2002 Count: [*] 3o;7f;21g [26 May 2016] Order Methanococcalesᵀ Balch and Wolfe 1981 Count: [*] 2f;4g [26 May 2016] Family Methanococcaceae Balch and Wolfe 1981 Count: [*] 2g [26 May 2016] Genus Methanococcusᵀ Kluyver and van Niel 1936 (Approved Lists 1980) Count: -