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Re: Platecarpus tympaniticus - how to analyze a nomen dubium



On 22 September 2010 02:46, Tim Williams <tijawi@yahoo.com> wrote:
> Mike Taylor answered this better than I ever could, but it's worth 
> emphasizing the point that suprageneric taxa should not be erected for a 
> single genus.  This used to be common practice, but it's totally unnecessary, 
> and frequently unhelpful.

Actually, I'd go further: even supraSPECIFIC taxa should not be
erected for a single species.  But we are of course stuck with the
binomial naming scheme that requires us to name a genus called
Xenoposeidon with a single species proneneukos when what we really
mean is just a species called Xenoposeidon-proneneukos with nothing
said about membership in a genus.  This is by far the biggest wart on
the synthesis of Linnaean nomenclature for species and phylogenetic
nomenclature for clades, and the reason why I had to name a genus at
all.  The real platonic truth is that Xenoposeidon (though it looks
like the genus part of a binomial) IS a species name; and proneneukos
(though it looks the species part of a binomial) is a useless
appendix.

Sorry to keep using Xeno for all my examples.  It's just so darned
apposite (and cool).


On 22 September 2010 04:58, Anthony Docimo <keenir@hotmail.com> wrote:
> If memory serves, you don't mind genus and species, but just not anything 
> above that.

So to reiterate my point, I mind genus, too.  But we're stuck with it.
 Because it's not just part of taxonomy (which is subjective) but of
nomenclature (which we need to be objective).


On 22 September 2010 06:24, Tim Williams <tijawi@yahoo.com> wrote:
> PhyloCode (which has yet to be implemented) states that if a clade name is 
> based on a genus name, that genus must be used as an internal specifier.  So 
> again, not only must Ceratopsidae (and Ceratopsinae) include _Ceratops_, but 
> _Ceratops_ must be included in the definition(s).

Actually, I think the PhyloCode leaves enough wiggle-room for us to do
what is obviously the right thing here: Article 11.7 is the relevant
one, and it says "In the interest of consistency with the rank-based
codes, it would be desirable for a clade whose name is converted from
a typified name under a rank-based code, or is derived from the stem
of a such a name, to include the type of the that name. Therefore,
when a clade name is converted from a preexisting typified name or is
a new or converted name derived from the stem of a typified name, the
definition of the clade name must use the type species of that
preexisting typified name or of the genus name from which it is
derived (or the type specimen of that species) as an internal
specifier."

But we don't have to convert the rank-based name Ceratopsia, typified
by Ceratops.  Instead we can make a brand new clade Ceratopsia,
anchored on whatever taxa we want, named not after an included type
but after the characteristic morphological feature of the clade's
member, i.e. a horned face.

That's what I'd do, anyway, if it fell to me.