How names work; was RE: Arum

Jim McKenney
Fri, 06 Apr 2007 20:59:01 PDT
Mary Sue wrote: ". So I must still be  confused about whether 
when there are subspecies they are considered different from the species 
which can still stand alone or whether when there are subspecies all of the 
plants are supposed to be divided into the subspecies if you can figure it

If I understand you question, I think I can help out a bit here. 

You have to keep in mind that there are really two completely different
things going on here. One is the process of determining the rank of the
entities in question - i.e. answering the questions "is it a species?" "is
it a subspecies? "is it something else?". One appeals to science to answer
this question. 

The other thing going on follows once the issue above is answered. That
second thing answers the question "what is the correct name for this
entity?" One appeals to the international rules of nomenclature to answer
this question. 

Because science rarely provides an unambiguous answer to the first question,
it follows that there will be varied applications of the rules in pursuit of
the answer to the second question. 

The rules of nomenclature are, if not cast in stone, at least printed on
paper for everyone to read and understand. Provided that everyone starts
with the same assumptions, the conclusions reached should be similar if not

For the first process alluded to above, the process of determining rank,
there are no codified rules; the whole process is based on an arcane, ever
shifting body of knowledge. In fact, speaking broadly, we're at crossroads
in terms of where those sands are shifting. Traditional taxonomy based on
morphology is slowly being marginalized by DNA studies. 

Now, with that in mind, let's look at the question Mary Sue asked. In
particular, let's focus on the part about "whether 
when there are subspecies they are considered different from the species".

Perhaps I misunderstand what Mary Sue is asking here, but as I read her
question it suggests that she, as so many non-systematists do, is confusing
the form, the appearance of the name, with what that name expresses about
the relationship of the entities named. 

Here's what I mean. For purposes of discussion, let's use the genus Crocus
and in particular the species Crocus kotschyanus as described by Mathew in
his work The Crocus. He assigns four subspecies to Crocus kotschyanus:
kotschyanus, suworowianus, cappadocicus and hakkariensis. Because of the way
the rules of nomenclature work, one of those subspecies has to be named
kotschyanus. We would write these names Crocus kotschyanus subsp.
kotschyanus, Crocus kotschyanus subsp. suworowianus, Crocus kotschyanus
subsp. hakkariensis and Crocus kotschyanus subsp. cappadocicus. As
gardeners, we typically shorten the written forms to Crocus kotschyanus
kotschyanus, C. kotschyanus suworowianus and so on. 

When the name is written Crocus kotschyanus suworowianus, common sense
(which in this case is misleading) prompts people to say that "suworowianus
is a form of kotschyanus". That is true, but not in the sense which most
people seem to mean it. You have to keep in mind that it is equally true to
say that "kotschyanus is a form of kotschyanus". If for instance you want
the plant known as Crocus kotschyanus kotschyanus, and you order simply
Crocus kotschyanus, you have no grounds to complain if your supplier sends
you any of the four subspecies: each is equally Crocus kotschyanus. (But who
among us would complain about getting the subspecies suworowianus when we
thought we would be getting subspecies kotschyanus?)

How often have you heard gardeners say "I want the pure species, not one of
the varieties" or something like that? When I hear someone say something
like that, it suggests to me that they do not know what they are talking
about. If the "varieties" in question are other subspecies of coordinate
rank with the subspecies whose name matches the name of the species, then
those other subspecies have equal claim on the specific epithet. I suppose
that what those in pursuit of the "pure species" mean is that they want the
subspecies whose name matches that of the species. But that subspecies is
no "purer" than any of the other subspecies. Don't be fooled by the way the
names are written - that's not English you're reading.

In the Crocus example, subspecies suworowianus is "pure" Crocus kotschyanus,
subspecies  hakkariensis is "pure" Crocus kotschyanus, subspecies
cappadocicus is "pure" Crocus kotschyanus, and yes, subspecies kotschyanus
is "pure" Crocus kotschyanus. 

Mary Sue, does that address your question? A little voice is telling me
"Jim, you made it worse!" I hope not. 

Jim McKenney
Montgomery County, Maryland, USA, USDA zone 7, where I'm in deep denial
because two inches of snow are predicted for tonight. 

My Virtual Maryland Garden
Webmaster Potomac Valley Chapter, NARGS 
Editor PVC Bulletin 
Webmaster Potomac Lily Society

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