Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         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 "Actinobacteria" Garrity and Holt 2001
                 Class Actinobacteriaᵀ Stackebrandt et al. 1997
                   Order Actinomycetalesᵀ Buchanan 1917 (Approved Lists 1980)
                     Suborder Propionibacterineae Rainey et al. 1997
                       Family Propionibacteriaceaeᵀ Delwiche 1957 (Approved Lists 1980)
                         [Genus Arachnia Pine and Georg 1969 (Approved Lists 1980)] see Genus Propionibacterium Orla-Jensen 1909 (Approved Lists 1980)
                           [Arachnia propionicaᵀ (Buchanan and Pine 1962) Pine and Georg 1969 (Approved Lists 1980)] see Propionibacterium propionicum corrig. (Buchanan and Pine 1962) Charfreitag et al. 1988