Flora van Nederland Haeckel (1866) - plants
   Division Spermatophyta Goebel (1882) see Phylum Spermatophyta Goebel (1882)
     Subdivision Angiospermae J. Lindley (1830) see Infraphylum Angiospermae auct.
       Class Dicotyledones see Class Magnoliopsida Brongn. (1843)
         Order Polygonales Dumort. (1829) see Order Caryophyllales Juss. ex Bercht. & J.Presl (1820)
           Family Polygonaceae Juss. (1789), nom. cons. - buckwheat family
             Genus Rheum L. (1753)
               [Rheum rhabarbarum × R. rhaponticum]