From: "Julius Boos" ju-bo at email.msn.com> on 1999.10.18 at 23:23:42(3767)
>Dear Wilbert,
Thanks for all the information on this interesting and often misinterprited
genus!! Question---is A giganteus in cultivation ANYWHERE?? There are
two species/varieties common in cultivation here, the only differences seem
to be the difference in color around the spines on the petioles/peduncles
(one has paler spots around each spine ) AND the difference in the
rhizomes, one grows horizoltally along the ground, the other almost
vertically, the spathes may be different colors, I am not sure.
Bjorn got his plants from the old collection at the Botanical Garden at
Frankfurt University. A little later on today I will forward to you a couple
of his letters with info. on his plant, it MAY be interesting or informative
to you. I have forwarded your wonderful info., and hopefully it will be
posted on Aroid-l, thanks so much again!!
Cheers,
Julius<
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>>Dear Julius,
Anchomanes giganteus is a perfectly good species (I've seen the type) BUT
the stuff in cultivation is not that species. I guess this has been said on
this forum several times but people are often blind to "taxonomy". The plant
described recently here, with white berries turning reddish-violet, is
Anchomanes difformis, the most common and widespread species in Africa. It
comes in a number of "forms", the typical one having a deep purple-brown
spathe and elongate ovaries of which the style points downward (see attached
scans). The other extreme of the variation range is a form often identified
at the species level as Anchomanes welwitschii, which has a pale pinkish
spathe and the styles being very reduced, yet still visibly pointing
downwards and being placed on the lower half of the ovary's upper surface
(unfortunately, I don't have scans available at the moment). I have done a
short, yet unpublished study-ette on this group and I agree with Engler,
that this A. welwitschii doesn't deserve species rank, so its name would be
A. difformis var. welwitschii. In the end it produces the same nice
colour-change of maturing berries, from white to reddish-violet. Also, as
with the other forms of difformis, it quite often produces these seeds
without pollination. The name Anchomanes hookeri, often figuring prominently
on aroid-l, also represents a form of Anchomanes difformis. One in which the
styles of the ovaries are exceptionally strongly verrucate. You will notice
in my close-up of the styles that in my plant they are clearly verrucate,
yet not as strong as is described for "A. hookeri". Nothing to make a fuss
about, just NOT a good species. That name should disappear entirely in
synonymy.
The complication is that in the the recent floras of the western African
states (e.g. Ivory Coast, Cameroon), ANOTHER species has universally wrongly
been labelled Anchomanes welwitschii. This is the plant that can also be
seen under that wrong name in several editions of Exotica. It has a bright
green spathe, and the stigmas are almost sessile on the ovaries and much
larger than those in A. difformis and its forms and much more centric on the
ovary (see scans). This species is Anchomanes dalzielii Rendle, a name that
has been totally ignored in the literature. I have planned to correct this
in a paper. Maybe something for Aroideana. This species produces bright red
berries (see scans) and that also separates it easily from A. difformis et
al. In the leafy stage, A. difformis and A. dalzielii can be easily
separated, since in the latter, the wedge-shaped top of the leaflets is much
broader than in A. difformis. In general, the leaflets are more robust in A.
dalzielii. A. dalzielii IS in cultivation and I wouldn't be surprised if
some Aroid-ellers have it, probably unknowingly.
Hope you enjoyed this little expose. If you think this is useful for
aroid-l, please send it through.
Cheers,
Wilbert<<
> -----Oorspronkelijk bericht-----
> Van: Julius Boos [mailto:ju-bo@email.msn.com]
> Verzonden: donderdag 14 oktober 1999 10:58
> Aan: Hetterscheid, W.
> Onderwerp: Re: Anchomanes gigantea
>
>
> Dear Wilbert,
> What`s the scoop on Anchomanes giganteus Engler (in Das
> Pflan., )?? Is
> this a 'good' species??
> Cheers,
> Julius
>
>
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