Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         Subphylum Isoëtophytinaᵀ Doweld (2001)
           Class †Lepidocarpopsida Doweld (2001)
             Order †Lepidocarpalesᵀ G.M. Smith (1938)
               1 Family †Cyclostigmaceae
               3 Family †Sigillariostrobaceae
               4 Family †Lepidocarpaceaeᵀ G.M. Smith (1938), nom. cons. prop.
               6 Family †Caudatocarpaceae
               8 Family †Sporangiostrobaceae