[Taxacom] confused phylogeny?

[Kenneth Kinman]

Hi Stephen,
       Good point.  If you look at their phylogenetic tree, Acoelomorpha
is clearly shown to be paraphyletic.  But they should actually have
stated that it is just a subclade of Acoelomorpha (namely
Nemertodermatida) which is shown as sister group to the rest of
Bilateria.                      
        However, whether to accept their overall  phylogeny is the real
question.  I suspect that it is really their Lophotrochosa which is
paraphyletic and at the base of Bilateria.  The only way I personally
can see Acoelomorpha at the base of Bilateria is if they are highly
derived descendants of very basal lophophorates which have since lost
the characteristic lophophore.  Either way, a paraphyletic Lophophorata
at the base of Bilateria is still the best bet in my opinion.           
          ---------Ken Kinman                        
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Stephen wrote:
can someone explain to me how to interpret this?conclusion from a
recent (2009) publication (doi: 10.1093/molbev/msp150): 
>Both inference methods robustly show a paraphyletic >Acoelomorpha as
sister group 
>to the other bilaterians 
how can Acoelomorpha be paraphyletic if it is the sister group to the
other bilaterians???