Holotype selection criteria

[Thomas G. Lammers]

At 03:00 PM 12/2/2004, Fabio Moretzsohn wrote:

 >>What prompted me to write the ill-drafted posting was a quote from
Winston (1999: 173): "A type-specimen may or may not be typical of the
species; the important point is that it provides a fixed reference for the
use of the name (Jeffrey, 1989)."  I think a non-typical type is a poor
selection, so I tried to come up with some criteria that might be used to
select such a type, and I wanted to know how some of you might defend that
point of view.<<

I think that Winston is stating how things *are*, rather than how they
*should be* done.  In other words, many types of *existing* names are not
typical of the species they represent, e.g., the type of the grass Tridens
flavus has yellow spikelets, even though this is a rare morph representing
less than 5% of the species (purple-red spikelets are the norm).  No one
would suggest intentionally selecting an atypical type today, but some of
our predecessors *did* for various reasons (often inadvertent) and we
cannot ignore their designations on the mere grounds of it being an
atypical representative.  The Codes of Nomenclature differentiate between
past practice that is tolerated and how we are to do things from here on
out.  This is such a case.
Thomas G. Lammers, Ph.D.

Assistant Professor and Curator of the Herbarium (OSH)
Department of Biology and Microbiology
University of Wisconsin Oshkosh
Oshkosh, Wisconsin 54901-8640 USA

e-mail:       lammers at uwosh.edu
phone:      920-424-1002
fax:           920-424-1101

Plant systematics; classification, nomenclature, evolution, and
biogeography of the Campanulaceae s. lat.

Webpages:
http://www.uwosh.edu/departments/biology/Lammers.htm
http://www.uwosh.edu/departments/biology/herbarium/herbarium.html
http://www.geocities.com/TheTropics/Resort/7156/lammers.html
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