Phylum Magnoliophyta Cronquist, Takht. & Zimmerm. ex Reveal (1996) see Infraphylum Angiospermae auct.
   Class Magnoliopsida Brongn. (1843)
     Subclass Rosidae Takht. (1967) see Superorder Rosanae Takht. (1967)
       Superorder Saxifraganae Reveal (1994)
         Order Podostemales Lindl. (1833) see Order Malpighiales Juss. ex Bercht. & J.Presl (1820)
           Family Podostemaceae Rich. ex Kunth (1816), nom. cons. - river-weed family
             Subfamily Podostemoideae Warm.
               Tribe Podostemeae
                 Genus Hydrobryopsis Engl., in Engl. & Prantl (1930)