Class Equisetopsida C.Agardh (1825) - horsetails see Subclass Equisetidae Warm. (1883)
   gymnosperms see Class Spermatopsida
     1 Subclass Ginkgooidae M.W.Chase & Reveal (2009), orth. inval. see Subclass Ginkgoidae Pax (1900)
     2 Subclass Cycadidae Pax (1894) - cycads
     3 Subclass Pinidae Cronquist, Takht. & Zimmerm. (1966) - conifers
     4 Subclass Gnetidae Pax (1894) see Class Gnetopsida Eichler ex Kirpot. (1884)