Date: Thu, 24 Feb 2000 17:32:34 -0800 (PST) From: Barry Meyers-Rice <bamrice@ucdavis.edu> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg544$foo@default> Subject: Sarracenia rosea: quick review
Hey folks,
I've found the time to give a careful reading of the new paper that
establishes the name Sarracenia rosea. Here is a summary of the paper, and
a few critical comments by myself.
Complete reference:
R.F.C. Naczi, E.M. Soper, F.W. Case, & R. B. Case, Sarracenia rosea
(Sarraceniaceae), A New Species of Pitcher Plant From The Southeastern
United States, SIDA 18(4): 1183-1206, 1999.
My Summary:
The authors have decided that Sarracenia purpurea subsp. venosa var.
burkii is sufficiently different from Sarracenia purpurea subsp. venosa,
and indeed Sarracenia purpurea, as to be classified as an entirely new
species. (This plant has been called the 'Louis Burke' form in the past.)
As a result, you may see the following "new" transformations...
S. purpurea subsp. venosa var. burkii --> S. rosea
S. purpurea subsp. venosa var. burkii f. luteola --> S. rosea f. luteola
S. rosea is different from S. purpurea in a number of features. The
flowers have pink petals (unique among all Sarracenia pure species), the
flower stalks are shorter, and there are subtle but consistent differences
in the sizes of floral parts and pitcher details.
My thoughts on the paper:
The paper presents a set of interesting measurements, and demonstrates
that one can show there are consistent differences between S. rosea and
the rest of S. purpurea. They do this with a number of scatter diagrams
and other statistical arguments. Indeed, 12 such characters are presented.
The authors have convinced me that the two taxa are different, and that
the plants called S. rosea deserve some unique name.
However, the question is, does the fact that you can *detect* minor
differences between two populations of plants warrant elevating both
populations to the status of separate species? Truly not! Subspecific
categories exist just for such minor differences in plant populations.
When you read this paper, think of how different on their plots S. rosea
would appear from S. flava! Clearly, S. purpurea and S. rosea are
extremely closely related, far more closely related to each other than
they are to other species in the genus. This says, to me, *lump them*!
Perhaps, PERHAPS, I could be convinced of elevating the var. burkii taxon
to a subspecific rank, but certainly not to a separate species.
Adopting the logic in this paper, we will soon see S. purpurea, a
reasonably natural species, split into dozens of new species based on
minor, local variations. Specimens of S. purpurea subsp. purpurea in new
england are, for example, very different from those in Canada. According
to the level of hair-splitting promoted in this paper, they might be
candidates for being new species.
I will admit one extremely strong piece of evidence for adopting the name
S. rosea for the S. purpurea subsp. venosa var. burkii plants, and that is
the presence of Fred and Roberta Case on this paper as authors. These two
people have an enormous amount of field experience that I would never
discount readily. Their acceptance of this new taxon has me scratching my
head.
**Note: my views do not necessarily reflect those of my coeditor, or
anyone else.
Cheers
Barry
------------------------
Dr. Barry A. Meyers-Rice
Carnivorous Plant Newsletter
Conservation Coeditor
barry@carnivorousplants.org
http://www.carnivorousplants.org
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