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  More on Arisaema erubescens
From: "Peter Boyce" <P.Boyce at lion.rbgkew.org.uk> on 1997.02.26 at 21:14:56(435)
Dear All but especially Paul, Ray & Roy

Firstly Paul, fear not. Nothing you said was taken as rudeness. Why should it be?
After all, this is a scientific debate and not a personal slanging match.

To kick off, I'd be very grateful for the reference/s of the paper/s
'scotching the issue of erubescens being the correct name for
consanguineum'. I have missed these.

For those not yet completely au fait with Sino-Hiamlayan Arisaema species,
the seminal papers are those of Hara (1971) (Univ. Mus., Univ. Tokyo, Bull.
No.2: 321 - 354), Noltie (1994) (Flora of Bhutan 3(1): 143 - 155) and
Li Heng's (1979) account in the Flora of China (vol. 13(2): 116 - 194).

Noltie contains no direct discussion of the problems associated with erubescens/
consanguineum, although he does support the split by using the name
A. consanguineum and referring to A. erubescens to say that a collection
so named has been identified as A. consanguineum.

Hara supports both names. However, there are numerous problems in
this paper (which, incidentally, forms the basis of Pradhan's delightful but,
sadly, flawed 'Himalayan cobra-lilies'). The main problem with Hara's
paper is that the author saw almost none of the types (the original
specimen used to describe a new taxonomic name) of the names he dealt
with and thus there are several interpretational anomalies. The types of
A. erubescens and A. consanguineum are both in Kew and I and
Li Heng spent some considerable time working on these in Dec. '95.

The Flora of China merges them. Unfortunately for us the flora is published in
Chinese and we will have to await the English-language version that is currently
being written. However, the gist of Li's argument is that in the wild 'erubescens'
and 'consanguineum' intergrade. Concerning the poise of the infructescence, an
often quoted 'character', this character is not reliable since the infructescence
begins erect and flexes as it matures. Thus specimens can be gathered,
depending upon their degree of development, that match either 'species' or fall
at some point between them.

The issue of A. concinnum is a red herring. This is a distinct species with
a rugose spadix tip and, most importantly. stoloniferous tubers (see
Murata (1987) Pl. Sp. Biol. 2: 57 - 66)

Onto the various points raised by Roy.

1. The stout bristle-like appendages are the sterile structures.
Their degree of development does vary but they are almost always
there and, even if 'absent' can usually be detected as small bumps.

2. Murata now lumps together formosanum and erubescens.

but

3. maintains kelung-insularis

4. Subsepcific taxa. Maybe but anything in this line will need extensive work.
In erecting subspecific taxa one implies that a relationship is
'proved'. Systematics now places enormous importance on 'proving'
evolutionary lineage based on single ancestory (monophyletic taxa)
and thus the 'random' placing of taxa at subspecific rank within
other taxa simply because they look similar is to be discouraged
unless exceptionally well supported.

5. Yunnan is a hub of erubescens variation and has a bewlidering array of
plants that are very little understood. When it comes to plant
variability many folk seem hell-bent on limiting the range of
variation so as to produce a fixed set of parameters. It's a good job
that zoological systematics generally isn't so dogmatic. Just imagine
if one attempted to do this to Homo sapiens (i.e. put an Ethiopian,
a Native American, an Australian aboriginal, a Swede, a Chinaman,
a Congolese pygmy, an Inuit and a Maori in the same room and then try
to produce a species description....) Anyone fancy undertaking a PhD?!

6. In Thailand and the Philippines A. erubescens occurs at altitude.
In Thailand I have seen on the summit of Doi Pui (1600 m) and Doi
Inthanon (2500 m) . In the latter locality forms occurs with chalky-white lower leaf
surfaces and scarlet and white spathes. This has been called A.
hypoglaucum.

7. There are delightful 'explanations' of the latin species epithets
employed in Arisaema in Pradhan's book. He claims that 'consanguineum'
means of the same blood (i.e. related to) A. erubescens. However, Schott
gives no explanation of his choice of epithet in the protologue of A. consanguineum.

8. CT369 is yet to be described. It is close to A. ciliatum but does
not match the type of this name.

9. As I alluded abov, there are bits and pieces published but nothing
yet finalized. The best place would be the English-language version
of the Flora of China Araceae.

Hope this helps or, at least, doesn't make anything worse!

Pete

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