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?]
             Class "Nitrospira"ᵀ 2001 [monotypic]
               Order "Nitrospirales"ᵀ 2001 [monotypic]
                 Family "Nitrospiraceae"ᵀ 2001
                   Genus Leptospirillum (ex Markosyan 1972) Hippe 2000
                     1 Leptospirillum ferriphilum Coram and Rawlings 2002
                     2 Leptospirillum ferrooxidans (ex Markosyan 1972) Hippe 2000
                     3 Leptospirillum thermoferrooxidans Hippe 2000