varia (rather theoretical stuff)

Jan Schlauer (Jan@pbc-ths1.pci.chemie.uni-tuebingen.de)
Mon, 21 Aug 1995 11:59:17 +0100

Dear Fernando,

*********************** RE: _Heliamphora_ ***********************

>They climbed up Mt.Roraima and then took a helicopter over to
>Mt.Cuquenam. (...) I believe the Heliamphora species in that area
>is H.nutans, right Jan?

Yes, most probably.

*********************** RE: comb. & stat.nov. ***********************

Still interested in this dull stuff, anyone...?

> I've also heard that if a new taxon is described as 'Drosera xxxxx
>var.yyyy' and another taxonomist comes by later on and decides that this
>new variety is actually a new species, he can elevate it to species level
>and completely dump the variety name 'yyyy' and use a totally new name.
>Yet if it was described as 'Drosera xxxxx ssp.yyyy', the subspecies name
>MUST be used as the new specific name and thus become 'Drosera yyyy'. Jan
>has told me that the first name with which the plant is described,
>doesn't matter if it was a var. or ssp., MUST be maintained.

Not exactly this way! Only if the *rank* of the taxon is *not changed*:
e.g if you transfer D.xxxxx subsp.yyyy
to D.zzzzz retaining the rank of subsp.,
i.e. you create D.zzzzz subsp.yyyy,
you have to retain the epithet "yyyy"
if this does not create an illegitimate
combination (it would be an
illegitimate combination if you e.g.
transferred D.xxxxx subsp.zzzzz to
create D.zzzzz subsp.zzzzz, an autonym
which does *not* apply to the
*typical* subspecies of D.zzzzz)

The same does apply to any other infraspecific rank (var., f., etc.).

NOTE: The TAXACOM standards recommend to abbreviate subspecies as "subsp."
rather than "ssp." because of a pretended danger of confusion (maybe some
legasthenics might confuse the plural of species "spp." with the singular
of subspecies "ssp."). So we should follow this recommendation.

If you *change the rank* (status) of the taxon (e.g. transfer D.xxxxx
subsp.yyyy as a variety to D.zzzzz) you can choose whichever legitimate
epithet you like at the new rank (how about D.zzzzz var.wwww?).
e.g. if you transfer D.xxxxx subsp.yyyy
to specific rank, you might call
the species D.zzzzz (if the name D.zzzzz
does not exist already for another species,
and if D.yyyy does not exist yet at
specific rank).

Anyway, if you choose to base a new combination on a specimen which is
already the *type* of a taxon, at least I would recommend to retain the
epithet of that taxon at the new rank if possible. In any case, you should
study the nomenclatural situation at the prospective new rank very
thoroughly before you install a new name there (it is rather easy to create
an illegitimate combination).

> Anyways, I find this matter of var. and ssp. very and confusing
>and am amazed that taxonomist still haven't come to any conclusion over
>which should be used.

Well, you should perhaps regard this as a result of scientific liberty. The
only thing prescribed by the ICBN is rank and inclusivity (e.g. a subsp.
may include several vars. but a var. may not include several subspp.). I
think as long as it is not even ruled unambiguously what is a species
(approximately ten different theories do exist at present), there should
not be any further regulation for infraspecific taxa.

*********************** RE: Typification ***********************

And now it starts to become really boring...

> Last of all, if you don't mind Jan, I'd like you to explain about
>the differences between the various TYPEs (like syntype, lectotype,
>etc.).

Essentially, a newly described taxon should be based on a HOLOtype (a
single element/e.g. herbarium sheet), possibly designing duplicates of this
specimen (preferably collected from the same plant/population) as ISOtypes.
Additionally, other specimens (e.g. from other locations) believed by the
original author to belong to the same taxon may be listed as representative
material. These are then PARAtypes.

Two major problems may arise later:

1. If the name of a taxon was originally based on several not identical
specimens (SYNtypes or COtypes, which is no longer allowed by the ICBN!),
it may be that these indeed belong to two (or even more) different taxa. In
this case, one of the syntypes (that one which most closely corresponds
with the original description or an accompanying illustration) has to be
selected as the "true" type of the name, a LECTOtype, the other syntypes
attaining a status like paratypes, duplicates of the lectotype becoming
ISOLECTOtypes. The name of the taxon originally based on syntypes is then
based on the lectotype (and the other former syntypes may be assigned to
other taxa).

2. If the holotype (and photos thereof, which are PHOTOtypes) is lost
(destroyed, forever stolen, etc.), one of the isotypes (if existing) must
be selected as the LECTOtype of the taxon, replacing the lost holotype. If
no isotypes do exist, the LECTOtype must be selected from the paratypes or
syntypes (if existing). If none of the original material (all specimens and
*illustrations* cited or depicted in the protologue) does exist, a specimen
which has no connection with the protologue (it should be the same taxon,
however!) may be selected as a NEOtype. The latest version of the ICBN does
allow selection of a NEOtype even if original material does exist if
several criteria (in the first line nomenclatural stability) are met with.

Kind regards
Jan