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. 2024
             Kingdom Bacillatiᵀ (Gibbons and Murray 1978) Oren and Göker 2024
               Phylum Bacillotaᵀ Gibbons and Murray 2021
                 Class Bacilliᵀ Ludwig et al. 2010
                   Order Caryophanalesᵀ Peshkoff 1939 (Approved Lists 1980)
                     Family Gemellaceae Chuvochina et al. 2024 [monotypic]
                       Genus Gemellaᵀ Berger 1960 (Approved Lists 1980)
                         1 Gemella haemolysansᵀ (Thjøtta and Bøe 1938) Berger 1960 (Approved Lists 1980)
                         2 Gemella asaccharolytica Ulger-Toprak et al. 2010
                         3 Gemella bergeri corrig. Collins et al. 1998
                         4 Gemella cuniculi Hoyles et al. 2000
                         5 Gemella morbillorum (Prévot 1933) Kilpper-Bälz and Schleifer 1988
                         6 Gemella palaticanis Collins et al. 1999
                         7 Gemella parahaemolysans Hung et al. 2014
                         8 Gemella sanguinis Collins et al. 1999
                         9 Gemella taiwanensis Hung et al. 2014