[Taxacom] PhyloCode & ICZN to "duke it out"?

Paul van Rijckevorsel dipteryx at freeler.nl
Sat Oct 6 01:18:41 CDT 2007

From: "Doug Yanega" <dyanega at ucr.edu>
> It is this point that I think I consider the most problematic aspect
> of the Phylocode; unless I'm wrong about how it works, when the
> constituency of a named clade is changed in subsequent phylogenies,
> in MANY cases this change will require that a NEW NAME be coined for
> the re-defined clade; under the Linnaean system, the name does not
> need to be changed, specifically because it *is* defined by a "point"
> rather than a "set" (to continue Rich's analogy).

> In essence, the difference between how the Phylocode and Linnaean
> systems treat a change in the circumscription of a group is: (1) in
> the Phylocode, you just create a new name, because the group which
> defined the older name no longer *exists*, and that older name cannot
> be used for a group with a different set of constituents. Therefore,
> any given name is extremely stable (it cannot be redefined), BUT when
> there are changes within a group, it prompts the creation of new
> names.

Yes, this appears to be true even of the recent publication in Taxon. In
dealing with the clade known as "euasterids I" or "lamiids", the authors
note that there are two competing circumscriptions, and they solve this by
naming both clades, as /Garryidae and /Lamiidae, respectively, with
/Garryidae conforming to the more common usage of "lamiids". Also see the
two names for different circumscriptions of the "core eudicots".

To touch upon a different matter entirely, I find it quite noticeable that
this name /Lamiidae is published only electronically (the paper exists in
two versions, a 44pp electronic version and a 25pp paper version). Depending
on how the finalized version of the PhyloCode is phrased, this potentially
could be a source of  trouble (possibly also for /Garryidae, as the
description on paper, refers to these /Lamiidae, published solely
electronically). Most likely, any problems can be circumvented in the "
"companion volume" of phylogenetically defined names that will be published
simultaneously with the first paper version of the PhyloCode".

In this respect it is also noticeable that the paper refers to clades as
circumscribed by Stevens, in the Angiosperm Phylogeny Website, version 7
(2006). As we all know, this site is updated regularly, and its content is
dynamic. Thus, future readers may run into trouble, trying to establish
exactly what was referred to.


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