Class Equisetopsida C.Agardh (1825) - horsetails see Subclass Equisetidae Warm. (1883)
   gymnosperms see Class Spermatopsida
     Subclass Gnetidae Pax (1894) see Class Gnetopsida Eichler ex Kirpot. (1884)
       Order Ephedrales Dumort. (1829)
         1 Family Ephedraceae Dumort. (1829), nom. cons. - Mormon-tea family