Domain Eucaryota
   Subdomain Chlorota Doweld (2001)
     Kingdom Chlorobiota C.Jeffrey ex Doweld (2001) - plants see Subkingdom Viridiplantae Caval.-Sm. (1981)
       Subkingdom Pteridobiotina Britton & A. Br. (1896)
         Superphylum Pteridophytanae Doweld (2001)
           Phylum Equisetophyta D.H.Scott (1900) see Division Monilophyta Cantino & Donoghue
             Class †Calamitopsida Endl. (1841) see Class Equisetopsida C.Agardh (1825)
               Order †Calamitales Eichwald (1852) see Order Equisetales DC. ex Bercht. & J.Presl (1829)
                 Family †Kallostachyaceae Doweld (2001) [monotypic] see Family Calamostachyaceae S.V.Meyen (1978), nom. cons. prop.
                   Genus †Kallostachys Brush & Barghoorn (1955)