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[pbruggeman at tiscali.nl]

hardy  Aroids)" <ARISAEMA-L at NIC.SURFNET.NL>
From: "pbruggeman at tiscali.nl" <pbruggeman at TISCALI.NL>
Subject: Re: Arisaema flavum ssp. tibeticum
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Dear Ellen,

It was never my intention to doubt your ability to 
interpret Guy's book, I was merely replying to the reactions that 
followed your first posting and hoped to clarify the current situation= 
a bit.

Since the original article by Murata on the 3 subspecies in 
1990 (which Guy follows in his book) several new facts have appeared 
that question the current delimitations between the 3 ssp. The most 
important thing to realise is that not all plants of A. flavum from 
Tibet are conform the description by Murata for subspecies tibeticum.=2=0
Many plants share the major characteristics of ssp. tibeticum but lack= 
male-only plants. As I have noticed myself during several visits to 
herbaria (and observations on living material), the charactristics 
currently used to distinguish between the 3 subspecies seem to occur in= 
all 3 to some extent. This means the characters described for typical=2=0
ssp. tibeticum do occur in the other 2 ssp. as well and thus can not be= 
linked exclusively to ssp. tibeticum. Even ssp. tibeticum can have a 
blotch in the throat so in that sense, yes, I doubt the occurence or 
absence of a blotch, the size and color of the flower or the flowering= 
well above or before the leaves are good characters to distinguish each= 
individual subspecies on. 

What remains is the occurence of male-only 
plants and the higher chromosome count and if proved to be stable, that= 
would probably be the only good difference between ssp. abbreviatum and= 
ssp. tibeticum as I mentioned at the end of my previous reply. However,= 
as with most Arisaema is the case, many articles and descriptions are=2=0
based on few collections which do not necessarily represent the  
natural variation of a species. Most people who have observed Arisaema= 
in the wild will acknowledge that and certainly the more widespread 
species can exhibit a huge variation. 

In the genus Arisaema several 
species are split into subspecies. These subspecies generally do not 
have overlapping distribution ranges or interbreed. With that knowledge= 
in mind, the moment it becomes apparent 2 ssp. of flavum occur in 
Tibet, yes, then I become sceptical, certainly if no serious population= 
studies have been done on Tibetan flavum to see whether both subspecies= 
indeed represent 2 evolutionary lines. Without proper knowledge of the= 
distribution ranges of both forms or assesment of the variation through= 
population studies I have some reservations because I know from 
experience that fieldwork can have surprising results in matters like=2=0
this and for many species a lot is still unknown.

Contrary to common 
belief is Arisaema-taxonomy still in its infancy and it is my personal= 
belief that the names of at least 40% of the currently known species 
should be viewed as provisional and to some extent will change through= 
fieldwork and DNA-analysis. Even then, taxonomy based on morphology 
(=E2=80=9Cthe visible features=E2=80=9D) is by nature subject=ive and depend=
s on the 
interpretation of the individual botanist, for instance how much weight= 
is put on specific characters in determining the taxonomic position of= 
a plant. It is up to the individual to agree or disagree with a certain= 
view and I do belief no view should be accepted as sacred or "true".

And on the subject of Arisaema flavum, even the taxonomic position of=2=0
subspecies abbreviatum in relation to the Arabian subspecies flavum can= 
be disputed. Subspecies flavum is separated from subspecies abbreviatum= 
through geograpical bounderies in Arabia but yet I have seen no proof=2=0
of any major morphological difference between them in herbaria or 
living plants. Geographic isolation in itself does not necessarily mean= 
a separate status is justified, something which is already shown in 
many other genera and even Araceae like the widespread Typhonium 
venosum. Arisaema tortuosum for example occurs in north as well as 
south India but both forms are separated by a region in central India=2=0
and have a high degree of differentiation on both sides. In S India a=2=0
local form of tortuosum occurs that predominantly produces a single 
leaf with very short petiolules. Would that be a new subspecies? I 
doubt it. 

Hopefully I have clarified my view a bit in this lengthy 
reply (or have I added to the confusion?) but I certainly did not want= 
to question your ability to interpret Guy's book, my remarks were of a= 
more general nature and it is obvious your plant is ssp. tibeticum. 
Hopefully you are able to propagate your plants because it is a very 
attractive plant and deserves to be more widely grown.

All the best,

Pascal