[Taxacom] Rankless classifications

Kenneth Kinman kennethkinman at webtv.net
Fri Mar 20 10:22:59 CDT 2009

Hi John,
      It's not the rank of Sarcopterygii that is the problem, it's the
ENORMOUS content change.  Sarcopterygii used to refer to just
coelacanths, lungfish and extinct relatives (less than a dozen living
species).  Now it is fashionable to throw in all the tetrapods as well
(about 25,000 species).  They should have given that clade a new name,
not hijacked Sarcopterygii and drastically changed its content.  This is
far worse than shifting hominids down to subfamily or tribe.    Anyway,
this basal group that they should call Sarcopterygii is definitely
paraphyletic with respect to tetrapods. I believe coelacanths split off
first, then lungfish, then Rhizodontiformes, then Osteolepiformes, then
then Panderichthyiformes, and then the tetrapods.  

      Their "diapsids excluding archosaurs" is even more paraphyletic.
It is equivalent to my Subclass Lepidosauria.  This is my latest
classification showing at least 10 clades (numbered) splitting off in
succession before getting to the archosaurs (Subclass Archosauria):
   Subclass Lepidosauria% (basal diapsids)
          1 Araeosceliformes
          2 Plesion Coelurosauravidae
          3 Plesion Apsisaurus
          4 Younginiformes
          ? Ichthyosauriformes
          5 Eolacertiliformes
          B Sphenodontiformes (tuatara)
          C Squamatiformes (lizards, snakes)
          6 Thalattosauriformes
          B Sauropterygiformes
          C Testudiniformes (turtles)
          7 Choristoderiformes
          8 Trilophosauriformes
          B Rhynchosauriformes 
          9 Protorosauriformes (prolacertiforms)
        10 Proterosuchiformes% 
        _a_ {{Archosauria}} 

      Note that I mark Lepidosauria as paraphyletic (%), as well as
including an {{Archosauria}} exgroup marker. You can take out the
turtles if you don't believe that they have secondarily lost the diapsid
condition.  I don't really blame them for leaving turtles in the
anapsids (it's still controversial). However, they should also label
"Extinct relatives of mammals" as paraphyletic.  It's just another way
of saying "mammal-like reptiles" or better yet "pelycosaurs and

       Anyway, I have no problem with unfamiliar names.  New fossils and
newly recognized groupings make it necessary.  It's all this unnecessary
destabilization just to avoid paraphyletic taxa.  And if you do put in
paraphyletic groupings, you should certainly label them as such.  They
could have very easily done it like the "Tree of Life", with several
parallel lines leading up to them (instead of a single line).  In
summary, I am clearly a cladist (I love clades), but I am not a "strict"
                  --------Ken Kinman

P.S.  They also misplaced the elephant-sirenian clade (actually part of
Afrotheria, which split off either just before or just after the
edentates).  And the "monotremes, marsupials, etc." grouping is also


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