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] Domain Bacteria Woese et al. 1990 [paraphyletic?] Superphylum Terrabacteria Battistuzzi et al. 2004 Phylum Firmicutes corrig. Gibbons and Murray 1978 (Approved Lists 1980) Class Clostridia Rainey 2010 Order Clostridialesᵀ Prévot 1953 (Approved Lists 1980) Family Peptoniphilaceae Johnson et al. 2014 Genus Helcococcus Collins et al. 1993 1 Helcococcus kunziiᵀ Collins et al. 1993 2 Helcococcus ovis Collins et al. 1999 3 Helcococcus sueciensis Collins et al. 2004