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]
           Clade "neomura" Cavalier-Smith 1987
             Domain Eukaryota Chatton, 1925 - eukaryotes
               Clade neokaryotes Cavalier-Smith 1993 - mitochondrial eukaryotes
                 Clade neozoa Cavalier-Smith 1993
                   Superkingdom Corticata Lankester, 1878
                     Kingdom Chromista Caval.-Sm. (1981) - chromists
                       Subkingdom Harosa Cavalier-Smith, 2010
                         Infrakingdom Halvaria Cavalier-Smith, 2010
                           Superphylum Heterokonta Caval.-Sm. (1981)
                             Phylum Ochrophyta Caval.-Sm. (1995)
                               Subphylum Khakista Caval.-Sm. (2000)
                                 Diatomea Kütz. (1844)
                                   Class Bacillariophyceae Haeckel (1878) - pennates
                                     Subclass Bacillariophycidaeᵀ D.G. Mann (1990) - raphid diatoms
                                       Order Rhopalodiales D.G. Mann (1990) [monotypic]
                                         Family Rhopalodiaceaeᵀ (Karsten) Topachevs'kyj & Oksiyuk (1960)
                                           Genus Rhopalodiaᵀ O. Müll. (1895)
                                             Rhopalodia acuminata Krammer (1987)
                                             Rhopalodia brebissonii Krammer (1987)
                                             Rhopalodia constricta (W. Sm.) Krammer (1987)
                                             Rhopalodia dubia (H. Peragallo & M. Peragallo) Paddock & P.A. Sims
                                             Rhopalodia gibbaᵀ (Ehrenb.) O. Müll. (1895)
                                             Rhopalodia gibberula (Ehrenberg) O. Müll. (1899)
                                             Rhopalodia musculus (Kützing) O. Müll.
                                             Rhopalodia operculata (C. Agardh) Håkansson (1979)
                                             Rhopalodia rupestris (W. Sm.) Krammer (1987)