[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain Bacteria Woese et al. 1990 stat. inval. see Domain Bacteria Woese et al. 2024
     Phylum "Aquificae" Reysenbach 2002 stat. inval. see Phylum Aquificota Reysenbach 2021
       Class "Aquificae" Reysenbach 2002
         Order Aquificales Reysenbach 2002
           Family Aquificaceae Reysenbach 2002
             Genus Hydrogenobacter Kawasumi et al. 1984
               1 Hydrogenobacter thermophilus Kawasumi et al. 1984
               2 Hydrogenobacter hydrogenophilus (Kryukov et al. 1984) Stöhr et al. 2001
               3 Hydrogenobacter subterraneus Takai et al. 2001