[Taxacom] Kingdom Protista (a preferable third optional coding?)

Kenneth Kinman kennethkinman at webtv.net
Tue Jul 21 21:35:49 CDT 2009

Dear All, 
         A recent paper (Hampl, et al., 2009; in Proc.
Natl. Acad. Sci.) indicates that the coding for the excavates (Clade 3)
needs a slight modification. Phylum Metamonada now appears to be sister
group to the other three excavate phyla (forming a new clade Discoba).
In other words Loukozoa and Metamonada have switched positions. As for
the problematic Family Malawimonadidae, I prefer to continue leaving it
in Phylum Loukozoa unless another placement can be shown to be more
       As for the problematic Phylulm Rhizaria, there is
actually a third alternative placement which now seems to me to be the
most likely, namely as sister group of chromalveolates (rather than
*within* chromalveolates as sister group to Heterokonta). This change is
also reflected in the recoded classification below. However, at this
time, note that I see no reason whatsoever to change the number or
contents of the 16 Phyla which I recognized in 2006. It's just a matter
of recoding.         
       The biggest remaining question (in my mind) is just
another coding question. Does Phylum Amoebozoa form an exclusive
anterokont clade (clades 2-9) as sister group to the bikonts (clades
3-9), as my coding still reflects?  Some molecular analyses show
Unikonta (clades 1-2) as holophyletic (strictly monophyletic), although
bikonts probably evolved from a unikont ancestor. I am still betting
that this unikont ancestor split off between opisthokonts (clade 1) and
Amoebozoa (clade 2), rather than some unknown ancestor of an
Opisthokont-Amoebozoa clade.  Only time and further analyses will tell
(we shall see). Anyway, unless I have overlooked some pertinent
literature, the coding of the classification below will remain my
classification of Kingdom Protista for 2009.        
 P.S.  If you want to recognize formal taxa between Kingdom and Phylum,
the best bet would be Subkingdoms Unikonta (clades 1-2) and Bikonta
(clades 3-9), although Unikonta would almost certainly be paraphyletic
at some level.  You could further subdivide Bikonta into Superkingdoms
Excavata, Plantae, and the SAR clade (i.e., Chromalveolata sensu lato?).      


   1   Choanozoa%% (= Mesomycetozoa)
 _a_   {{EUMYCOTA}}
 _b_   {{METAZOA}}
   2   Amoebozoa
   3   Metamonada (incl. Parabasalia)
   B   Loukozoa (jakobids and allies)
   C   Percolozoa
   D   Euglenozoa
   4   Glaucophyta
   B   Rhodophyta
   C   Chlorophyta%
 _a_   {{METAPHYTA}}
   5   Rhizaria
   6   Cryptophyta
   B   Haptophyta
   C   Heterokonta (stramenopiles)
   7   Ciliophora
   8   Dinozoa (or Dinophyta)
   9   Sporozoa 
NOTES: Clades 6-9 make up the Chromalveolate clade. Clades 5-9 make up 
the recently discovered "SAR" clade. Clades 4-9 is the photokaryote
clade (sensu lato). And of course, clades 3-9 still forms the bikont

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