[Taxacom] Pteridophyta

[Kenneth Kinman]

Hi Mario,
      Thanks for that discussion on the paper by Smith et al, 2006.
Their classification seems to be a big improvement.  If one adds two
extinct classes (Rhyniopsida and Trimeropsida), you might end up with a
classification something like the following (with clade 4 being the four
Classes of monilophytes):
 
PHYLUM PTERIDOPHYTA%
     1  Rhyniopsida (extinct)
     2  Lycopsida (incl. Zosterophytes)
     3  Trimeropsida (extinct)
     4  Psilotopsida 
     B  Equisetopsida 
     C  Marattiopsida   
     D  Polypodiopsida 
     5  {{Spermatophyta}}  (= Pinophyta + Magnoliophyta)        

          --------Ken Kinman      
P.S.  Note that I classify the extinct Class Progymnospermopsida as a
basal member of Phylum Pinophyta.  The same phylogenetic topology could
be shown with Progymnospermopsida splitting off between the monilophyte
clade and the Spermatophyta.  Does anyone have any preference whether
Class Progymnospermopsida is placed in Phylum Pteridophyta or at the
base of Phylum Pinophyta?  I guess in part that it might depend on where
one thinks the angiosperms (Phylum Magnoliophyta) split off.