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  Re: Philodendron selloum
From: "Julius Boos" ju-bo at email.msn.com> on 2001.12.14 at 02:21:18(7908)
Dear Petra, Donna and Friends,

In the interest of clarity, I will just give a LITTLE more information taken
from Simon Mayo`s EXCELLENT paper, "A revision of Philodendron subgenus
Meconostigma (Araceae)', published in the Kew Bullitin Vol. 46 ( 4 ), and
then give my OPINION (and as we all know, opinions are like noses, EVERYONE
has one :--)> ).
Dr. Mayo takes great pains to point out that this is a very confused taxon,
occuring in a WIDE area of distribution, and may consist of several species,
some as yet undescribed. The two main ones in question are P.
bipinnatifidium Schott 1832, and P. selloum C. Koch1853 or 1854, (some
confusion here).
Dr. Mayo writes as follows---'P. bipinnatifidium, as circumscribed here is a
very variable taxon in morphology and color of leaf and inflorescence. The
main unifying character is the bipinnatifid leaf blade'---he goes on to
state--'Like other authors who have studied this species complex in the
recent past'---'I have taken a broad view of the species. This seems to be
the only practical way of dealing with taxanomic difficulties for which
current knowledge does not provide satisfactory soloutions'. He goes on to
explain that the original dsecription was by Schott ---(plant probably
collected from near Rio de Janero) and that Schott`s manuscript description
of 1884 show that his plant had a spathe tube colored purple-brown
externally, a gynoceum with a well developed central style dome and the
female zone adnate to the spathe for about half it`s length.
P. selloum was described by C. Koch (to cut a long story short, it was from
cultivated material in Berlin sent to Koch by his friend H. Sello, head
gradener at Sans Souci, the Imperial Prussian estate at Potsdam, and Koch
did not see fertile material). Dr. Mayo notes that the confusion between
these two names may have it`s origin in the professional rivalry between
Schott and Koch. Schott left illustrations in his Icones Aroideae of his
P. bipinatifidium and P. selloum, and his illus. of P. selloum showed a
spathe colored green externally, a pistil with a deep style funnel and NO
central dome , and the female zone of the spadix adnate to the spathe for
OVER half its length. Engler (1878: 170), who studied Schott`s
illustrations, distinguished P. selloum by its green spathe tube longer than
the spathe blade, and the entirely adnate female zone. This work by Engler
is probably the 'why' of the two names, and when Mayo wrote this paper I am
quoting from is when people began considering that the two species were
synonomyous.
Now for MY opinion ( which is like a nose, etc. etc. etc.). Based on what
I have just detailed, I concur with Dr. Mayo that MUCH more study needs to
be done with this complex before I can say with certainity whether there are
two or even more species involved in this group of broadly distributed
plants, BUT based on the features of spathe color (exterior and interior),
size of the respective inflorescences, and especially the seemingly major
differences in the structure of the female flowers and the length that the
female portion of the spadix that is adnate to the spathe, that there
probably are at LEAST two species involved here, so as it stands now P.
bipinnatifidum and P. selloum can be distinguished one from the other, and
in my opinion may eventually be 'ruled' to be two 'good' and different
species.
The plants that I have studied here in Florida all have an all-green spathe
exterior, I have not as yet sen a plant with a purple-brown spathehe
exterior (I THINK someone told me there were plants w/ red-brown spathes in
collections??).
Another 'species' that has been placed into synonomy with P. bipinnatifidium
by in Dr Mayo`s in paper is
P. pygmaeum Chodat & Vischer 1880 from Paraguay, I THINK I`ve seen a plant
of this VERY distinctive small Philodendron, (any of you who were in Miami
last Sept. may have seen me on Sat. morning wandering around with a leaf of
this plant in my hand). There is a paper in which there must be a
discussion on this plant, it is by Dr. Croat and D. Mount. I`d like to
read the section about it, if anyone has a copy please contact me, it
is--'Croat, T. B. & Mount, D. (1988) The monocotyledons- A Comparative
Study. 378 pp., Acadamia Press, London.'
This is a MOST interesting discussion, and Donna`s information given below
gives me ammunition to go ask my old buddy Jim about! He will remember the
names and ways these plants used to be sold in the 'good old days'.
ENOUGH!

Good growing,

Julius Boos

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