[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020] Domain "Archaea" Woese et al. 1990 Phylum "Euryarchaeota" Garrity and Holt 2001 Class Methanococci Boone 2002 Order Methanococcales Balch and Wolfe 1981 Family Methanocaldococcaceae Whitman et al. 2002 Genus Methanocaldococcus Whitman 2002 Methanocaldococcus infernus (Jeanthon et al. 1998) Whitman 2002