1 Natura - nature
   2.1 actualia - actual entities
     2 Mundus Plinius - physical world
       3 naturalia - natural bodies
         2 Biota
           3.2 Domain Eukaryota Chatton, 1925 - eukaryotes
             2 Bikonta
               2 Diaphoretickes Adl et al., 2012
                 2 Kingdom Chromalveolata Adl et al., 2005
                   2 Sar Adl et al., 2012
                     1.2 Alveolata Cavalier-Smith, 1991
                       1 Phylum Ciliophora (Doflein, 1901) Copeland, 1956 - ciliates
                         9 Subphylum Intramacronucleata Lynn, 1996
                           3.3 Class Oligohymenophorea de Puytorac et al., 1974 - oligohymenophoreans
                             3 Subclass Peniculia Fauré-Fremiet, in Corliss, 1956
                               2 Order Urocentrida Jankowski, 1980
                                 3 Family Parameciidae Dujardin, 1840
                                   2 Genus Parameciumᵀ O.F. Müller, 1773
                                     Paramecium putrinum Claparède & Lachmann, 1859