Phylum [Tracheophyta] Sinnott ex Caval.-Sm. (1998) - vascular plants
   Subphylum Polypodiophytina Reveal (1996) [monotypic]
     Class Polypodiopsida Cronquist, Takht. & Zimmerm. (1966) - ferns
       Subclass Polypodiidae Cronquist, Takht. & Zimmerm. (1966)
         Order Schizaeales Schimp. (1869)
           Family Lygodiaceae M. Roem. (1840) [monotypic] - climbing ferns
             Genus Lygodium Sw. (1801), nom. cons.