Imperium naturæ C. Linnaeus, 1758 - nature
   Mundus Plinius - physical world
     naturalia - natural bodies
       Regnum Animale C. Linnaeus, 1758 - animal kingdom see Kingdom Animalia Linnaeus, 1758
         Class Vermes Linnaeus, 1758 - worms see Phylum Vermes (C. Linnaeus, 1758)
           Order Testacea Linnaeus, 1758
             Genus Arca Linnaeus, 1758
               * Margine integerrimo; Natibus recurvatis
               ** Margine integro; Natibus inflexis
               *** Margine crenato; Natibus recurvatis
               **** Margine crenato; Natibus inflexis