Very clear and message received. I guess it's hard for us amateurs who do|
not have access to herbarium material, microscopes, gynoeciums and locules
(let alone flowering material - my old P. 'williamsii' is at least 20 years
old and has never flowered) to try and identify the plants in our
I am surprised that your plant has never bloomed, from what I know it blooms
on a regular basis here in Florida, and hybrids have been created with it
and P. bipinnatifidum!. It is unfortunate that most species MUST depend on
examination of the sexual parts, color of dried herbarium specimens, etc.,
but I don`t make the rules! I wait till someone tries to do the revision
of Urospatha, I feel that it may yet involve the smells of the different
For myself, the tendency to rely on what I can observe of the plants is
perhaps overwhelming at times, especially when the division between
species may come down to microscopic structural differences in their
flowers. Having further examined my old 'williamsii' and new stenolobum, I
am struck by the similarities in petiole cross section and trunk
appearance, with the only apparent 'difference' being the leaf blade shape
and its stiffness.<<
This makes my point exactly, were we in the wilds of Brazil, I would warrant
that we would see populations, ALL being P. stenolobum, but differing one
from the other in leaf shape, texture, etc. BUT---as collectors and human
beings, we`d choose only the 'more beautiful' plants from a population which
we`d collect, NOT the more drab, less 'shapely' specimens!! This happened
to Lynn, Mary, my brother Hans and myself when we visited Joep Moonen in Fr.
Guyana ( a trip I HIGHLY recomend to plant people!!), there was a species of
climbing/rambling Philo. there that was exceedingly common EVERYWHERE, even
around the capital city, quite an attractive plant, and we collected a few
as just samples. BUT---then Joep so very kindly took us to visit his
secret and 'private reserve' population of this SAME species, a VERY small,
restricted population, all growing in a tiny valley, all growing against the
trunks of stunted trees. MAN! WOW!!! HELL!!!! Extra- long, extra
narrow leaves, shorter, horizontal and BRIGHT orange petioles and leaf
veins, very compact growth habit!!! We were allowed, under Joep`s expert
eyes and guidance, to collect only a VERY limited number of tip-cuttings,
thus preserving the population, and these cuttings and their divisions are
treasured by their owners, and when rarely available at auction, go for big
$$ here in Miami!!! Man GENERALLY selects the most attractive individuals
of several populations of either plants OR animals to suite his personal
This problem with P 'williamsii' would appear to go a long way back. I
have a copy in my files of a beautiful coloured drawing and the first
description of P. williamsii in one of the early botanical publications,
the Botanical Magazine (5899) - the plant looks like stenolobum more than
the longer bladed variation. The author had the initials of JBH (Hooker?)
and he described the plant as being sent to Kew by Mr Williams of Bahia,
giving it the name of Philodendron williamsii. The paper has a date of
May 1871. A question for Eduardo. Is this the true P.williamsii you refer
to which is only known from some herbarium material? or was this plant
misnamed from the start.<<
NOW you have tickled my DEEP interest! We MUST wait for Eduardo`s reply
and determine IF this old illustration AND DESCRIPTION entered into his
research and decisions on P. stenolobum and P. williamsii!! I hope Dr.
Goncalves manages to reply soon! Any chance of scanning this illus. to the
list??? Look out for the copyright BS.
Cheers, Best Wishes, and Good Growing!
On 03/07/2005, at 6:48 AM, Julius Boos wrote:
Sent : Saturday, July 2, 2005 7:40 PM
To : Discussion of aroids
Subject : Re: [Aroid-l] Philodendron stenolobum
I still do not think you guys understand what is being said--- ALL these
photos that are being discussed, plants with the longer narrower ruffled
leaf blades, the long FLAT leaf blades, the slightly shorter leaf blades
with or without ruffles, slightly longer lobes, slightly shorter lobes, ALL
are variations from different collections throughout the range of P.
stenolobum, a range FAR distant from where TRUE P. williamsii occurs. NONE
of the plants being seen or discussed are a different species OR P.
williamsii. Leaf shape or leaf lobe shape/length play a VERY minor role
in the determination of species. ALL the plants pictured and being
discussed should or will have barrel-shaped gynociums (not flask-shaped as
in P. williamsii), ALL will have only 7-8 locules (not 11-12 as is found in
P. williamsii) and all will fall within the anterior leaf blade ratio of P.
stenolobum, so ALL will be classified as P. stenolobum, NOT another
species, and NOT P. williamsii. If it rings your bells, or makes them
more expensive/easier to sell, knock yourself out and give them 'cultivar'
or 'var.' names, but this only confuses the issue further.
Read and understand Dr. Goncalves recent postings.
Very nicely put!
As you say, some cultivated samples may tend to be
those that are "extreme" samples from the wild, and
thus are not truly representative of the "average"
look of the species (that is, the wild population may
form a continuum of plant forms).
The pic of one of the leaves of that small plant
called "P. williamsii" shows short lobes but with
edges that are ruffled (and some of newer leaves just
coming out are starting to get even more 'wavy'):
I looked at pics of P. stenolobum from that paper and
they look similar in lobe shape to the short form - so
maybe it's the "long lobe" form that needs a new name
But, honestly, i do like the ones with longer, thinner
lobes though ;-)
--- Julius Boos wrote:
Reply-To : Discussion of aroids
Sent : Friday, July 1, 2005 9:21 PM
To : Discussion of aroids
Subject : Re: [Aroid-l] Philodendron stenolobum
Eduardo has informed us of exactly what the case is
w/ these two very different and 'good' species (see his letter of
30th, 8.18 pm, addressed to 'Tom" (Dr. Croat), but allow me one more
on what might have and may still be causing some confusion.
[By the way, the leaf ratios asked for on these two
species are---"Anterior division (ratio length/width)
P. williamsii--1 - 1.5.
P. stenolobum 2.1 - 3.3.
(these are copied from Dr. Gonclaves' paper)
Other critical differences that separate these two
species documented by Dr. Goncalves in his paper are--The gynoceum
fruit) in P. stenolobum is flask-shaped, while that of P. williamsii is
barrel shaped. The ovary of P. stenolobum has 11-12 locules (chambers)
that of P. williamsii has only 7-8.]
Before Dr. Goncalves published his paper, when
word got out that the plant that we all had been refering to as P.
was going to be described as a new/good species, several collectors/growers
then assumed that only the plants with the ruffled leaf edges were this new
species ( P. stenolobum), and the plants with the not-so-long anterior
and flat leaf blades must still be P. williamsii--- we were wrong! The
P. williamsii is a completely different species, seemingly not in
cultivation, rare in herbarium collections, and very different looking to
either one of the vars. of the now-new P. stenolobum, and grows FAR away
from all the different populations of the new P. stenolobum. (see
Eduardo`s recent letter on this).
So--the plants that have a very long leaf, both the
ruffled and the unruffled, ALL are TRUE P. stenolobum. Man ALWAYS
gravitates to collecting from wild populations what he views as the most
attractive or even odd members of a broard variety of either plants or
animals, it happens all the time with collectors, but true scientists
'down the middle', a representitive sample that illustrates the extremes
of a species. This obviously pertains to the plants under discussion,
all seen are P. stenolobum.
Could you give numbers for the ratios? I'm
and glad this conversation came up.<<
--- Russ wrote:
The leaves on my 'stenolobum' are nowhere near as
ruffled as the one in last year's Aroid show, or
2 pictures I found
of P. 'williamsii' in my Exotica. But they seem to
be the same in narrow lobe width and proportions.
So, these are obviously >both stenolobum with a
variation in the leaf edge. BUT, these are not the
two opposing plants I have in mind as questionable.
The 'old williamsii' >that I'm referencing has much
shorter, and wider lobes, and leaves are not as
thick or stiff. They truly do not look like the
same species. Russ>
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