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 Methanococci Boone 2002 [monotypic] 1 Order Methanococcalesᵀ Balch and Wolfe 1981