Species in the Collection
Rainforest Tour
Orchids
The
Exotic Rainforest
Plants in
the Exotic Rainforest Collection
Images on this website are
Copyright protected. They are not in the public domain! Contact us before
attempting to reuse.
Detailed information on Growing Anthurium Species
Click this Link
Within our collection we have many species of Anthurium. If you are seeking other photos, click this link:
Anthurium
jenmanii
Engl.
Often confused with Anthurium bonplandii subsp. guayanum
Additional photographs by botanist David Scherberich can be seen here: http://www.aroidpictures.fr/GENRES/anthuriuma-l.html
includes French Guiana, Suriname, Guyana, Venezuela and the extreme
northern portion of the Amazon basin in Brazil's Amazonas State.
Anthurium jenmanii is almost
always collected at elevations below 500 meters (1650 feet) in moist forest
regions but also in open
dry woodlands.
My friend
Dutch
naturalist
Joep Moonen (pronounced yupe) who lives and works in French
Guiana has
indicated in multiple personal communications the species is often observed very near sea level.
Joep can be seen in the photo at the top of this page with an adult specimen
of Anthurium jenmanii.
The leaf blades of
Anthurium jenmanii are coriaceous (leathery to the touch) and broadly
oblanceolate to elliptic but are rarely ovate-elliptic.
Any leaf
blade that is oblanceolate is spear shaped but widest above the center of
the blade and broadest near the middle or in the
upper one fourth. The leaf blades near the base are obtuse (blunt) and rounded or
may be slightly
oval. The edges (margins) of the blades are moderately undulated
(wavy). The upper blade surface
(adaxial side) is semi-glossy to glossy and is a yellowish green. The lower
leaf surface (abaxial side) is matte to
only slightly glossy and is a bit paler in color. In regard to
the color of the blades show at right, Joep wrote,
"Please notice the
yellow leaves. This is normal in the dry season when they are exposed to a
lot of light such as on inselbergs. I know one inselberg where
there are hundreds if not a thousand A. jenmanii specimens but deep in the
forest the species is a lot less common."
There should be 5 to 13 primary
lateral veins on each side of any leaf of Anthurium jenmanii.
The veins near the top of the blade merge into the collective
vein The collective vein is a specialized vein which runs around the
circumference of an Anthurium's blade and is a primary characteristic
used to determine if a specimen is, or is not, an
Anthurium
species. The lateral leaf veins are raised near the midrib (center of
the leaf) but are slightly sunken at the edges
(margins). The
minor veins, known as the tertiary veins, are sunken on the upper surface
but are raised
on the leaf's underside.
The lower surface (abaxial) of the leaf blade is substantially less glossy than the upper (adaxial) blade surface. The leaves of Anthurium jenmanii are often both large and coriaceous to moderately coriaceous. The term "coriaceous" simply means leathery to the touch. The upper blade's surface is semi-glossy as well as moderately bicolorous (dual colored). The midrib is convex (pushes upwards) on both the upper and lower surfaces while the tertiary (lesser) veins are sunken on the upper surface but raised on the lower surface.
Anthurium jenmanii is known to be variable having multiple leaf forms throughout its native range. This link offers a more complete explanation of natural variation within aroid and other plant species. Click here.
The petioles of Anthurium jenmanii support the blades are described in
the journals of aroid botanist Dr. Thomas B. Croat
Ph.D., P.A. Schulze Curator of Botany
at the Missouri
Botanical Garden in St. Louis as being sharply to slightly "D" shaped
but are flattened to slightly convex on the upper surface while rounded on the underside. The surface
of
Anthurium jenmanii's petiole is
slightly speckled.
The "D" shape is a reference to the appearance of the petiole when cut and
viewed as a cross section (cut in half). The petiole is
scientifically a stalk to which the lamina of the leaf blade is attached. The petiole is often referred to by collectors as the
"stem"
but correctly the stems are the base of the plant.
At the top of any Anthurium species' petiole you will find the geniculum which is slightly larger than the petiole in size. The geniculum allows the leaf blade to rotate and orient itself to find a brighter source of light. The geniculum of Anthurium jenmanii is slightly paler and only moderately thicker than petiole. Anthurium jenmanii has short internodes on the stem. An internode is a segment of stem between two nodes and the node is where a leaf may emerge.
Once a new leaf is produced, it is surrounded by a sheath-like structure known to a botanist as the cataphyll. The cataphylls of Anthurium jenmanii are lanceolate (lance shaped) and sometimes purple. A cataphyll is a bract- like modified leaves that surround any new leaf and whose purpose is to protect the emerging leaves as they develop. On a specimen of Anthurium jenmanii the cataphylls remain after drying as a fibrous material similar to coconut husk.
During the year 2007 aroid collectors from Indonesia were paying phenomenal prices for a single specimen of various plants being sold as "Anthurium jenmanii". More than a few specimens were hybrids, not the species Anthurium jenmanii. One principal reason collectors in Indonesia were seeking what they thought to be "Anthurium jenmanii" was they believed that species produced a juvenile bright burgundy to red leaf. Knowing for certain if Anthurium jenmanii does or does not produce a red leaf is questionable according to botanical experts. My friend Joep made this comment in a personal email, "I have never seen a red jenmanii but that does not say much since they have a big distribution and there might be mutations as well".
Based
on
an exchange of personal email with Dr.
Croat in 2007 the plant often being sold as Anthurium jenmanii
on eBay and
in
Indonesia is unlikely to be that species.
Dr. Croat sent this response to an Indonesian collector when asked if a
specimen similar to the one at the right was truly Anthurium jenmanii,
Dr. Croat wrote,
"Your
plant is what I treated as Anthurium bonplandii Bunting var. guayanum
(Bunting) Croat. Some still call this Anthurium guayanum but I
chose to consider it a variety of A. bonplandii owing to the immense
variation in both species. Anthurium jenmanii Engl. is very different,
having a spathe that soon falls off and also by lacking the dark
punctuation on the lower blade surface."
The glandular punctations of
Anthurium bonplandii subsp. guayanum can be seen here:
Click
this link
In a message to expert aroid grower Denis Rotolante who with his son
Bill own Silver Krome Gardens in Homestead, FL, Dr. Croat
wrote:
"There
has not been anything published since I published my revision of
Anthurium sect. Pachyneurium in the Annals of the Missouri Botanical
Garden 78(3): 539-855.1991. The attractive, coriaceous bird's nest
sometimes called "jenmanii" sometimes A. bonplandii guayanum,
sometimes as A. guayanum had the young leave reddish on the lower
surface when young. I treated this as Anthurium bonplandii ssp.
guayanum but it might just as easily be considered a distinct species
as was treated by George Bunting. It is just
that there is so much
variation in all of those taxa that I could not find clear
separation in them. Certainly this plant did not have anything
really in common with A. jenmanii, a species which has a spathe
that soon withers and falls off. "
According to Dr. Croat the
species that produces the purple-red leaf is Anthurium bonplandii
subsp. guayanum.
Specimens bearing the name "Anthurium jenmanii" are often either hybridized forms (not pure species) or plants that may be erroneously using the name. As an example, the plant sold in Indonesia as Anthurium jenmanii Cobra is a hybrid form with an unknown parentage. Although a beautiful specimen, it is not representative of the species known to science as Anthurium jenmanii.
Growers too often elect to use a scientific name on the
specimens they
sell without regard to the botanical characteristics of
that species. Just
because the seller's tag says "Anthurium
jenmanii" does not mean the plant is truly
Anthurium jenmanii. The difference
between horticultural names and botanical science is vast. The true
Anthurium jenmanii does not produce the purple/red leaf
blade when young while Anthurium bonplandii guayanum
does.
An examination of the photos included on this page shows the obvious differences in the two species but there are also technical scientific differences (red the text just above) including the fact Anthurium bonplandii guayanum has a petiole that is either "C" or "D" shaped and is also sulcate. Sulcate indicates small grooves running parallel along the petiole. Anthurium bonplandii subsp. guayanum also has a cataphyll that does not persist as fibers. Very importantly the species Anthurium bonplandii subsp. guayanum has blackish dots on the abaxial (underside) of the leaf blade known as glandular punctates while Anthurium jenmanii does not. You can read about and see the glandular punctates of Anthurium bonplandii subsp. guayanum here.
an inflorescence (photo, left) known to science
as a spathe and spadix. Most people believe the spathe is a
"flower" which is incorrect. The spathe is a modified leaf
whose purpose is to protect the spadix at the center of the
inflorescence. During sexual anthesis there are very tiny
flowers found on the spadix when the plant is ready to produce seeds. In order to
produce those seeds the female flowers must first be pollinated as
they reach their own sexual
anthesis. When ready to reproduce the
spadix grows both male, female and sterile flowers. Those male
flowers produce pollen and If the
female flowers are pollinated by an appropriate
Cyclocephala
beetle which carries pollen from another
Anthurium jenmanii
specimen which is already at male anthesis pollination will result. If the female
flowers are successfully pollinated
the spadix will begin to grow berries containing 1 to 2 seeds.
However, it is unusual for most Anthurium
species to be capable of self pollination (see the very tiny seeds
of
Anthurium jenmanii
below). The production of an
inflorescence on Anthurium jenmanii is not uncommon in
collections and both the spathe and spadix are purple in color but
may also be a lighter color on the upper surface of the spathe due
to natural variation. Dr. Croat noted the
spathe is both spreading and reflexed (turned backwards). 
f you truly have an Anthurium jenmanii, the berries containing seeds will be obovoid and reddish/purple but pale in color
while almost white at
the base. Joep made this
observation regarding berry coloration and seed shape in both Anthurium
jenmanii and Anthurium bonplandii guayanum,
"The berries and
seeds from both species have the same color: purple-red, fading to whitish
at the base. However the shape is different. Anthurium jenmanii : oval
like an egg, Anthurium bonplandii: shorter seeds, they look triangular to trapezium
from the side."
Despite common misconceptions, species within the
neo-tropical genus Anthurium are not found naturally in Asia or the
Pacific region but that does not mean they are not grown all over the
world! People obviously grow Anthurium species in
many countries, but
Anthurium are not
naturally found in the Pacific basin or
Asia and are strictly found naturally within Mexico, Central
America, South America, and the West Indies.
My thanks to Dr. Croat for his input and the use of his published material. Thanks also to botanist David Scherberich, Jardin Botanique de la Ville de Lyon, Parc de la Tete d'Or, France for the use of his photographs of Anthurium jenmanii as to to Phil Nelson and Harry Luther at the Marie Selby Botanical Gardens in Sarasota, FL. And finally to my friends Joep Moonen, Bill Rotolante and aroid expert Leland Miyano for their assistance.
Joep Moonen
along with his wife Marijke and son Bernie live and work at their
Emerald Jungle Village in the rain forests of French Guiana. A Dutch
naturalist who regularly takes botanists and scientists into the rain
forests of the Guiana Shield to search for new and undiscovered animal
and plant specimens, Joep has been honored by having several species including Anthurium moonenii,
Philodendron moonenii
and others named to science in his honor.
If you enjoy spending time in a rain forest
filled with exotic creatures and extremely rare exotic plant species
Joep Moonen will enjoy introducing you to the rain
forests of northeast South America. The Emerald Jungle Village website can be found at http://home.planet.nl/~gumamaus/