Natura - nature actualia - actual entities Mundus Plinius - physical world naturalia - natural bodies [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020] Clade neomura Cavalier-Smith, 1987 Domain Archaea Woese et al. 1990 [paraphyletic] Phylum Euryarchaeota Garrity and Holt 2001 Class "Methanomicrobia" Order Methanomicrobialesᵀ Balch and Wolfe 1981 Family Methanomicrobiaceaeᵀ Balch and Wolfe 1981 Genus Methanogenium Romesser et al. 1981 [Methanogenium aggregans Ollivier et al. 1985] see Methanocorpusculum aggregans (Ollivier et al. 1985) Xun et al. 1989 [Methanogenium bourgense Ollivier et al. 1986] see Methanoculleus bourgensis corrig. (Ollivier et al. 1986) Maestrojuán et al. 1990 [Methanogenium frittonii Harris et al. 1996] see Methanoculleus thermophilus corrig. (Rivard and Smith 1982) Maestrojuán et al. 1990 [Methanogenium liminatans Zellner et al. 1990] see Methanofollis liminatans (Zellner et al. 1990) Zellner et al. 1999 [Methanogenium marisnigri Romesser et al. 1981] see Methanoculleus marisnigri (Romesser et al. 1981) Maestrojuán et al. 1990 [Methanogenium olentangyi Corder et al. 1988] see Methanoculleus olentangyi (Corder et al. 1988) Maestrojuán et al. 1990 [Methanogenium tationis corrig. Zabel et al. 1986] see Methanofollis tationis (Zabel et al. 1986) Zellner et al. 1999 [Methanogenium thermophilicum Rivard and Smith 1982] see Methanoculleus thermophilus corrig. (Rivard and Smith 1982) Maestrojuán et al. 1990 1 Methanogenium cariaci Romesser et al. 1981 2 Methanogenium frigidum Franzmann et al. 1997 3 Methanogenium marinum Chong et al. 2003 4 Methanogenium organophilum Widdel et al. 1989