[Taxacom] cyperaceae

[Ken Kinman]

Nige,
     Actually the range is wider than that.  Peter Stevens' website 
(Angiosperm Phylogeny Website) lists only 98 genera for Cyperaceae.  I 
suppose some of the larger numbers could possibly be lists that include 
extinct genera, but I doubt that is the case is here.

      More likely it is just lumping versus splitting.  At family level, 
some workers might include (lump) the closely related Juncaceae in 
Cyperaceae, or perhaps even Thurniaceae as well.  This would be similar to 
some zoologists lumping parts of (or even all of) Pongidae into Family 
Hominidae.

      But the most likely cause of the range in numbers of genera is various 
lumping or splitting of the genera themselves.  The low number of 98 on the 
Angiosperm Phylogeny Website is not surprising.  If a strict cladist finds 
that a genus is paraphyletic, they will often combine (lump) it with the 
daughter (exgroup) genus.  If the exgroup genus is morphologically distinct, 
other workers will continue to regard it as separate genus.  But strict 
cladists don't always lump, and will instead split up a paraphyletic mother 
genus.  With all these varied philosophies of how inclusive or exclusive a 
given genus should be, it is not surprising that various workers get 
different numbers of genera in a large family.
    ------Cheers,
             Ken Kinman
********************************
>From: blackstock8 at aol.com
>To: Taxacom at mailman.nhm.ku.edu
>Subject: [Taxacom] cyperaceae
>Date: Wed, 05 Sep 2007 06:49:51 -0400
>
>Many thanks for the replies re: the number of genera in the Cyperaceae.? It 
>would seem that there are between 104 - 122.? How do we account for the 
>difference in numbers?
>
>I am particularly interested in the ref Thorne & Reveal (Botanical Review 
>73:67-182. 2007).? Unfortunately I can't get easy access to this paper.? 
>Does anyone have a copy of the abstract?
>
>Cheers
>
>Nige
>________________________________________________________________________

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