Classification (Kingdom PROTISTA)

Ken Kinman kinman2 at YAHOO.COM
Sun Mar 5 17:08:19 CST 2006

Dear All,
      Since the 5-Kingdom system has been so popular for so long, I'm going to (temporarily?) give it a try here.  To convert it to my preferred 4-Kingdom system, you can simply replace the exgroup marker {{EUMYCOTA}} with the 3 eumycotan Phyla----Eomycota (incl. microsporidians), Ascomycota, and Basidiomycota.  In any case, I will not use the name "Fungi" as a formal taxon name (Eumycota is far more precise for the true fungi).  And I certainly will not recognize a 6th Kingdom for the Chromista clade (Cryptophyta, Haptophyta, and Heterokonta).  Following the classification, I will further discuss various subclades of Protista.

     Anyway, the total is 16 Phyla of protists (and it would be 19 phyla if you included the 3 phyla of Eumycota). The Apusozoa may need to be split off from Rhizaria, but I expect virtually all of the other "candidate" phyla will actually turn out to fit nicely into one of the phyla listed below.  We certainly do NOT need a bunch of new eukaryotic kingdoms.  As always, the main clades are numbered in the order in which they split off phylogenetically.

                   KINGDOM PROTISTA

  1   Choanozoa (= Mesomycetozoa)
 _a_   {{EUMYCOTA}}
 _b_   {{METAZOA}}
  2   Amoebozoa
  3   Rhizaria
  4   Loukozoa (jakobids and allies)
  B   Metamonada (incl. Parabasalia)
  C   Percolozoa
  D   Euglenozoa
  5   Glaucophyta
  B   Rhodophyta
  C   Chlorophyta
 _a_   {{METAPHYTA}}
  6   Cryptophyta
  B   Haptophyta
  C   Heterokonta (stramenopiles)
  7   Ciliophora
  8   Dinozoa (or Dinophyta)
  9   Sporozoa
    NOTES:  Clade 1 is the opisthokont clade, which is sister to the anterokont clade (clades 2-9).  Phylum Amoebozoa is sister to the bikonts (clades 3-9).  Phylum Rhizaria is sister to the corticoflagellates (clades 4-9).

    Clade 4 is made up of the four excavate phyla (of which Percolozoa and Euglenozoa make up a discicristate subclade).  Excavates are sister to the photokaryotes (clades 5-9).  Clade 5 is the plant clade, which Cavalier-Smith calls Plantae, and it also equals the Archaeplastida clade of Adl et al., 2005.  And finally we have the chromalveolates (three phyla of chromists and three phyla of alveolates)---still the "crown group" after all these years.  :-)
                   Ken Kinman

P.S.  I've forgotten who coined the term "exgroup".  I did a google search for paraphyletic + exgroup, but all the hits lead to various posts by mine (but I didn't coin the term myself).  Anyway, an exgroup is simply the taxon which one removed from a mother group (making the latter paraphyletic).  Reptilia has two exgroups (Mammalia and Aves), thus making it doubly paraphyletic.

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