A. erubescens vs. A. consanguineum - P. Boyce, et al.

[George R Stilwell, Jr.]

Dear Folks

There seems to be much confusion concerning Arisaema consanguineum,
both apropos it's name and appearance. Now, I'm by no means au fait
with all the complexities of temperate Asian Araceae but, over the past
couple of years, I've been tring to get to grips with A. consanguineum
and its kin and now feel that it's time to make available the data of
which I feel confident.

Well, to kick off, the bad news is that the correct name for this plant,
by priority, is Arisaema erubescens (Wall.) Schott. It is identifiable
(sensu latissimo) by the following combination of characters:

One or two leaves with few to many radiate very narrow to rather
broad acute- to long acuminate-tipped leaflets. Inflorescences with
a smooth auricles and a short to long caudal appendage, a smooth-tipped
stipitate spadix with the expanded part tapering basally and the stipe
with
few to many stout sterile structures, some of which may be reduced and
fused to the base and lower portion of the expanded part of the appendix.

Spathe colour varies from dingy greenish brown (many Chinese clones) to
strikingly dark red and white striped (Thai, Taiwanese and Philippines).


Arisaema ciliatum is very similar (as are A. taiwanense, A. echinatum
and any number of Chinese species with species epithets ending
-shanense). Arisaema ciliatum has spathe limb auricles furnished with
distinct, rather stout, marginal cilia and a spadix with a truncate
to cochleate (stipe 'embedded' into the expanded part, the lower
margins of the appendix thus appearing to 'hang' over the stipe apex).
The few clones in cultivation are are highly coloured with deep
red-purple and greenish white spathes.

Arisaema taiwanense has a spongy tip to the spadix appendiux  and
very distinctly marked pseudostem/petioles (caramel, cream and
olive-green).

Arisaema echinatum has the spadix appendix tip with prominent, rather
sharp, denticules.

Hope this helps

Pete

Peter Boyce
Royal Botanic Gardens, Kew
p.boyce at lion.rbgkew.org.uk

Peter,

I quite agree on the dates of the original citations for A. consanguineum
(1859) and A. erubascens (1832). However, are they indeed the same plant?
Udai Pradhan, in his 1990 book, shows significant differences in flower
structure, leaflet number and shape, spathe color and shape, etc. I
suspect the original citations do as well.

Thus from this evidence I would have to conclude that, even though
closely related and often confused, they are not the same plant and thus
both names are valid.

Perhaps you have other evidence to show the differences are not valid?

Ray
GRSJr at Juno.com

Dear Peter (and other Arisaema enthusiasts),

Thank you very much for the information. Does this mean that the picture
on
the Arisaema home page (Chinese), Arisaema species 'CT369' is
A.erubescens
(A.consanguineum)? We do have this clone and I did identify it as
A.consanguineum last year.

Can you give me a reference (article/literature) about the correctness of
the name A.erubescens (for A.consanguineum). I would be much obliged.

With best regards, Eric

Peter, All,

This is my first posting to the group, I hope that it gets through.

I have taken a while to reply, both to consult and to make sure that
nothing
that I said in haste was interpreted as rudeness.

I was under the impression that the idea of erubescens being the
"correct"
name for consanguineum had been scotched, and I am not alone in thinking
this.

It has been reasoned I think, that the two taxa are the same species and
I
am sure that you are correct Peter in your researches and that erubescens
has priority.  I would say that this is not the issue however, as the
priority only holds IF erubescens is the same species as consanguineum.
If
the two are different species then both names stand.

For what it is worth I, and again others, think that the two are
different.
This is something that needs checking carefully and urgently before the
name
issue gets muddled. It has been done once, wrongly with Arisaema
erubescens
already.

If name changes are to be brought in it is vitaly important not to repeat
the kind of mistake that was made with Pleione.  A flawed study resulted
in
horticulturists being told to call P. formosana by the "correct" name of
P.bulbocodioides.  We were lumbered for years with a totally incorrect
name
change, when the status quo PRE the study turned out to be the right one
after all, the correct name WAS P.formosanum.  Sorry to mix my genera but
this mess still confuses nursery lists and show benches twenty years
later.

I am being general and trying to wear both my botanical hat and
plantsman's
hat at the same time, but to fly a kite, is not A. erubescens (if it even
exists) closer to, or the same as, A. concinnum......

Please, Peter especially, don't take this as an attack, that is not
intended, but it is a contribution to a debate where one must be careful.
Anything with "KEW" associated become gospel before the ink is dry.

Hope this helps too

Paul Christian
bulbs at celtic.co.uk

Pete et al:

Whoops, looks like it may be time to update the Arisaema Page. But before
I
do, a couple of questions:

1. Has the observation by Hara that A. erubescens has an erect
infructescence been determined to be erroneous?

2. I've just been reading the 1996 article by Jenn-Che Wang on 'The
systematic study of Taiwanese Arisaema' which describes A. consanguineum
in
detail. In an accompanying photograph, I was surprised to see the base of
the spadix of a female inflorescense covered with stout bristle-like
appendages. Are these the same as what you refer to as 'stout sterile
structures'. I don't recall seeing any in the consanguineums I grow, but
I
may have missed them. Has anyone else observed them?

2A. Wang also notes that A. consanguineum and A. formosanum are very
similar in morphology as well as habit, and may hybridize with one
another
in the wild. Is there any talk of lumping formosanum with
erubescens/consanguineum, or is the thickness of the spadix appendage
enough to keep them separate?

3. Has A. kelung-insularis been lumped with A. consanguineum, and
therefore
with A. erubescens?

4. Can we expect any varieties or subspecies of A. erubescens to be
recognized? Just to further confuse things, I note that an 1879
publication
lists A. erubescens var. consanguineum-- looks like they were mixed up a
long time ago.

5. In Yunnan last fall I saw an incredible range of variation in plants
of
what we though were consanguineum/erubescens. I'm sure it is possible
that
they all could be one species, but I wonder if this is really true. Is
Heng
Li confident that there is a single species, or does she think some
splitting may take place? Whatever the case, it certainly is an adaptable
plant, growing in every sort of environment, wet or dry, sun or shade,
from
6000' (perhaps lower) to over 11,000'.

6. From Thailand and the Phillipines, too? Are these growing far up in
the
mountains, and can any be considered tropical?

7. Pardon my ignorance of Latin, but I just looked up 'erubescent' and
found out it means red or reddish. Hey, the consanguineum I grow is all
green! (not even close to dingy brown) Speaking of Latin, just what is
the
'same blood' that consanguineum refers to?

8. What's the latest theory on CT369?

9. Any idea when or if this change in nomenclature will be published?

Still confused,
--Roy Herold

Peter,

Very interesting. Thanks for sharing the references with us.  I do have a
translation of the Key from Flora of China done at the National
Arboretum. It does identify A. erubescens but does not even mention A.
consanguineum. Hopefully the descriptive portion of the document does do
that, but I do not have a translation of that. I do have a partial
translation, not in computer form, and will search that.

The section of the key on A. erubescens shows:

Arisaema Sect. 13 Sinarisaema

1. Spathe throat margin entire.
2. Appendix apex glabrous.
3. Leaflets 14, undulate-margined; appendix thick-clavate,
narrowed to base,
upper part to 1 cm thick.

70. A. undulatum Krause
3. Leaflets entire.
4. Leaves 2.
5. Leaflets 9, oblanceolate; spathe purple with white
striae,
blade with linear cauda to 12 cm long; appendix thin, 7 cm x 1 mm.

71. A. oblanceolatum Kitamura
5. Leaflets 11, linear-lanceolate; spathe green with
white striae, blade with linear cauda 4.0-4.5 cm x 5-6 mm, female
appendix with numerous
sterile flowers.

72. A. biradiatifoliatum Kitamura
4 Leaf 1.
6. Petiole longer than leaf blade; appendix more or
less with sterile flowers.
7. Spathe green with white striae; leaflets 7-13.
8. Appendix thin, 4-5 cm x 1 mm, slightly
recurved, sparsely covered with sterile flowers below.

73. A. formosanum Hayata
8. Appendix thicker, 5-6 cm x 2-4 mm, middle
and lower parts with obtuse sterile flowers to 7 mm long.

74. A. kelung-insulare Hay.
7. Spathe green or purple, with or without white
striae; appendix narrowed toward base and apex, 2-4 cm long, 2.5-5.0 mm
thick in middle, lower part with sterile flowers; leaflets few or more.

75. A. erubescens (Wall.) Schott
6. Petiole shorter than blade; leaflets 13, 30 x 6-7
(-10) cm.

76. A. brevipes Engl.
2. Appendix apex ciliate or rugose.
9. Appendix clavate, stipitate, 2.2-6.0 cm x
5-9 mm, apex densely echinate for more than 0.7 mm.

78. A. echinatum (Wall.) Schott
9. Appendix thin-cylindric, sessile, 2-4 mm
thick, apex rugose, lower part with numerous sterile flowers.

77. A. concinnum Schott
1. Spathe throat margin oblique-truncate, ciliate, blade violet-purple
with greenish white striae that nearly reach the blade margin.

79. A. ciliatum H Li

and so on.

Ray
GRSJr at Juno.com

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

Peter Boyce

A less-than-scientific addendum to this debate: last year I bought seeds
of A. erubescens/whatever from the Seed Guild, which, I believe, got them

from Kunming BG.  The seedlings are now in their second dormancy (just),
and I have noticed two things:

(a) they certainly did exhibit enormous variability in their first true
leaves: leaflets ranged in shape from extremely narrow to moderately
broad,
and a few had lovely silver central variegation.

(b) the corms, though only around 2cm in diameter (pretty fast-developing
for seedling arisaemas), made masses of little offset corms (cormlets?) -
many on the order of 4 or 5 per parent.  Was it Roy Herold who referred
to it affectionately as the "weed of Yunnan"?

Ellen Hornig

Dear Ray,

Arisaema consanguineum is a synonym of A. erubescens in the Chinese
Flora of China. As far as I know, it will be the same in the English
version we are working on.  This species is a well known herbal plant
in China.  I would appreciate if you could send me a copy of the
key translated from the Flora of China.

Guanghua Zhu
gzhu at lehmann.mobot.org