Dear Alan,

Your work is good and of course I appreciate the information that
molecular studies provide.  However, these studies are valid when there
are differences to be found.  In the case of Melongena corona (sensu
lato) the molecular study was uninstructive.  This could be because
there are no differences or because the genes chosen were not the ones
that would help.

I also might mention a real problem with molecular studies is the lack
of conchological vouchers.  Now all of the these sequences are in a gene
bank but the molecular scientists seem to have little concept as to what
they are calling what.  I point out an example from Duda & Kohn, 2005
(Molecular Phylogenetics and Evolution 34:257-272).  An entity
identified as Conus centurio grouped with a number of other western
Atlantic species (C. daucus, C. poormani, and C. villepinii, Figure 1,
the 16S phylogram).  All we know is that this specimen is Genbank
accession number AY382002.  I can say that this particular sample is not
C. centurio.  C. centurio is closely related to C. delessertii.  These
are possibly part of a single polytypic species.  Conchologically, they
are about identical excepting coloration.  Their radulae are identical
and both have the same structures on the anterior end of the tooth
including a barb, blade, and posterior blade.  These structures occur in
C. delesserti and in other small major clade species.

I expect that the shell identified as C. centurio was really C. sanderi
or some other large major clade species.  So far as I can tell I have no
way to find out what AY382002 actually looked like.  This to me is a
weakness in the use of sequences from snail with no vouchered
conchological specimen.

Finally, I have a comment on Melongena corona.  I have been somewhat
amazed by the some of the comments made in the past.  Has anyone
actually read Florida Museum of Natural History Bulletin 36(7) where I
described M. sprucecreekensis?  The species was not founded on its large
size but on comparisons of meristic traits using analysis of
covariance.  In fact, I did all that I could statistically to remove
size as a variable.  Some spoke of the need for gaps in the linear array
of populations that Melongena forms.  The paper points out two such
breaks in shell morphology.  One is at Cedar Key where the Suwannee
River enters the Gulf and the other is in the Florida Bay.  These are
illustrated in Figure 2.  johnstonei and corona do intergrade but the
intergrade zone is narrow and distinct.  Morphologically there is no
real evidence of an intergrade zone between bicolor and sprucecreekensis
or for that matter bicolor and corona.  I thus prefer my original
hypothesis of three species on the Florida coast.  The molecular
evidence may not be there yet but the morphological evidence is sound.
Citing one variant after another as proof my hypotheses are wrong is
less than useful.  Tell me how many spines the population has and
present ANCOVA demonstrating where the POPULATION fits would be more
meaningful.

Yours,



John K. Tucker



John K. Tucker

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