[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain Bacteria Woese et al. 1990
     Phylum "Thermotogae" Reysenbach 2001
       Class Thermotogae Reysenbach 2002
         Order Thermotogales Reysenbach 2002
           Family Thermotogaceae Reysenbach 2002
             Genus Fervidobacterium Patel et al. 1985
               1 Fervidobacterium gondwanense Andrews and Patel 1996
               2 Fervidobacterium islandicum Huber et al. 1991
               3 Fervidobacterium nodosum Patel et al. 1985
               4 Fervidobacterium pennivorans corrig. Friedrich and Antranikian 1999