TYPE specimens

Fernando Rivadavia Lopes (ferndriv@usp.br)
Fri, 20 Oct 1995 14:40:58 -0500 (CDT)


(Just a warning: the text below will be EXTREMELY boring to those of
you who are not Jan Schlauer or who are not interested in taxonomy.)

As you may have read in my most recent letter to you (I'm not
sure if you received it yet) I recently met a German Biologist named Rolf
Grantsau who has been living in Brazil for over 30 years. He has worked
mainly as an ornithologists (hummingbirds, toucans, seagulls, etc.), but
has also put his hands into orchids, fish, snakes, dendrobates, lizards,
lichens, and others.
I've been talking a lot with Mr.Grantsau since we met, which
has been very productive as he has very ample knowledge on taxonomy,
from his experience with the numerous different taxonomic groups
mentioned above. A few questions have come up regarding classification of
new plant species which you will probably have a good answer for and
which I believe others on this list might be interested in hearing about.
Here is the problem. As I understood it from Mr.Grantsau, when
someone describes a new bird species, for example, the description in the
author's publication refers to a single, specific stuffed bird specimen
deposited at some museum. All the measurements and characteristics given
are taken from this single holotype specimen. In the same paper, the
author can give further measurements and details based on the paratypes,
other stuffed bird specimens which he considers to be conspecific with
the new species he is describing.
Now what caught me by surprise was that Mr.Grantsau told me the
same is worth for plants. That is, the holotype for a new plant species
is a single herborized specimen, and not (as I thought) a herbarium sheet
with numerous specimens considered by the author to be conspecific.
Of course using several specimens as holotypes can lead to much
confusion if in the future another person comes along and decides that
among those specimens there are 2 or more distinct taxa. Then what
happens? Do you maintain the original name for those specimens which
most resemble the original description and classify the other specimens
with different names? Or does this invalidate the original name and new
names have to be given to the 2 or more new taxa?
It truly sounds more logical to use a single herborized plant as
the holotype, to avoid future problems. In this case the chosen holotype
specimen could be circled on the herbarium sheet and the others on that
sheet would be considered syntypes.
What's confusing me though is that in the papers I have
describing new CP species, it seems like the authors always refer to
numerous specimens when giving the description which usually goes in
Latin. As I understood it from Mr.Grantsau, this is wrong. As I wrote
above, he told me that the description which validates your new species
is based on a single holotype specimen, though in the same article you
can include further descriptions of the syntypes and paratypes. So there
would actually be 2 separate descriptions in a single article, but I've
never seen this.
A further complication for this method is that you can't give a
full description based on a single holotype in your paper since you
often have to destroy the plant to take measurements of small structures
like stamens, pistils, fruit, stipules, etc. So you would have to measure
all the structures on your holotype which don't involve taking it apart
(like leaf length, shape, etc.) and then use syntypes or paratypes to
measure the other details. But then wouldn't you be risking involving other
specimens which in the future may come to be called by a different name?
So apparently, the correct way to go is to include one description
based on the measurable parts of the holotype (this being the true
validation of the new species) and another description based on para
and syntypes (which would go along with article just as extra
information). Yet all the articles I have, old and new, have only a
single description based apparently on numerous specimens, so I imagine
the above is not how it's done.
Could you, Jan, or anyone else try to clear this up for me? I
have a feeling I wasn't very clear myself, so just ask if you have any
doubts about what I wrote above. Basically the questions are:

1.) Is the holotype a single specimen or can it be more than one for

2.) When you publish a new plant species, should the description be
based on a single holotype or on various specimens which the author
considers to be conspecific? ......2 descriptions?

3.) In the case of various holotype specimens, would the species be
invalidated if in the future someone decides that those specimens
represent 2 or more distinct taxa?

4.) In the case of a single holotype specimen, would you have to
write 2 descriptions in your paper, one based on the holotype and
another based on paratypes and syntypes (the latter for additional
info and also to give the details which can not be measured from the
single holotype which can not be taken apart)?

Fernando Rivadavia
Sao Paulo, Brazil