anthurium jemani

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Anthurium jenmanii Engl.   Anthurium jenmanii Engl. Many sellers sell Anthurium bonplandii subsp. guayanum and call it Anthurium jenmanii The two species are very different species. All technical data was taken from Dr. Thomas B. Croat's journal Annals of the Missouri Botanical Garden 1991, Volume 78, #3 as well as from his field notes published on the Missouri Botanical Garden website TROPICOS.   For additional photos of Anthurium jenmanii see pages 803 and 804 of that journal.  The scientific description of Anthurium jenmanii can be found on page 662.      NOTE:  This text contains photos of both Anthurium jenmanii and Anthurium bonplandii subsp. guayanum.  Please read the captions beneath each photo.   A member of Anthurium section Pachyneurium which contains the "birds nest" forms, Anthurium jenmanii was first scientifically  collected on the Caribbean island of Trinidad.  Even though collectors often believe Anthurium jenmanii is rare in nature it is commonly found on the windward islands of the southeastern Caribbean including Tobago, St. Lucia, Martinique, Dominica, St. Vincent, Montserrat, Antigua and Grenada.   The species grows either terrestrially, as an epiphyte (eip-FIT) on the branches of a tree or as a lithophyte (litho-FIT) on stone.   Anthurium jenmanii is also found in South America's Guiana Shield  which 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 shown at right, below, 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 (see photo below).  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).   However, due to natural variation in the species Anthurium jenmanii may also be sulcate which indicates a depression (C shaped) in the stem (see photo right taken in the greenhouse of the Missouri Botanical Garden collection).  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 stem is at the base of the plant.   At the top of any Anthurium species' petiole you will find the geniculum (see photo right, above) which is slightly larger than the petiole in size.  The geniculum allows the leaf blade to rotate much like an elbow or a knee in order to 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 of other plant species, not the actual species known to science as Anthurium jenmanii.  One principal reason collectors in Indonesia were seeking what they thought to be  "Anthurium jenmanii" was they believed the species produced a juvenile bright burgundy to red leaf.  Anthurium jenmanii does not produce a red leaf according to botanical experts including aroid botanist Dr. Croat.  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".   As a result it is likely that 95% of the photos labeled "Anthurium jenmanii" on Google images are not Anthurium jenmanii but instead are a hybrid of Anthurium bonplandii subspecies guayanum.  All the photos labeles as Anthurium jenmanii on this page were taken either in the wild or are from the vouchered botanical collections of either the Missouri Botanical Garden in St. Louis, MO or the Jardin Botanique de la Villa in France. 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 not Anthurium jenmanii but instead 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.  Too often growers elect to use a scientific name on the specimens they sell without regard to the botanical characteristics of the 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 (read the text just above).   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. All Anthurium species are aroids.  An aroid is a plant that reproduces by growing 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.   The color of the spathe is variable within the species Anthurium jenmanii as can be observed in the photos on this page.   During sexual anthesis there are very tiny flowers found on the spadix when the plant is ready to produce seeds.  An aroid, all Anthurium species reproduce via the production an inflorescence and the stalk that supports the entire inflorescence is the peduncle. When an Anthurium is "in flower" the reference is to the tiny flowers containing both male and female sexual parts that grow on the spadix at the center of the inflorescence.  Unlike plants in the genus Philodendron which contain imperfect flowers having only a single sex Anthurium possess perfect flowers containing both sexes.  To help prevent self pollination nature has designed the female flowers to be receptive before the male portion of the flower produce their pollen so in most cases an insect must bring pollen from another plant.   In order to produce those seeds the female portion of the flowers must first be pollinated as they reach their own sexual anthesis.  When ready to reproduce the spadix produces the   flowers.  Those male portion of flowers produce pollen and If the female portion is pollinated by an appropriate Cyclocephala beetle which carries pollen from another Anthurium jenmanii specimen which is already at male anthesis pollination is likely to result.  If the female flowers are successfully pollinated the spadix will begin to grow berries containing 1 to 2 seeds.  Since Anthurium species are unisexual and produce both sexes on a single flower it is possible for the plant to be self pollinated (see the very tiny seeds of Anthurium jenmanii below, left).  The production of an inflorescence on Anthurium jenmanii is not uncommon and both the spathe and spadix are purple in color.  The spathe may be a lighter color on the upper surface due to natural variation.  Dr. Croat noted the spathe is both spreading and reflexed (turned backwards as in the photo right).    If 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."     According to naturalist Joep Moonen who guides botanists and environmental professionals in French Guiana into the rain forests of northern South America, Anthurium jenmanii is neither rare nor common.  It is simply as average as any Anthurium in the genus.  However, Anthurium bonplandii subsp. guayanum is truly considered rare.   After reviewing the information and photographs on this page, Joep suggested I add these notes, "I agree with the photos and text.  Anthurium jenmanii is locally common in transitory forest: which is the forest between high primary and lower vegetation like grass- or brush savannas.  Also A. jenmanii can stand a lot of direct sunlight. The leaves turn yellow, but the plants do not die."     Aroid expert Leland Miyano in Hawaii offered this opinion after reviewing the material on this page, "I have grown what I believed to be Anthurium jenmanii for years.  At this point in time, I am not so sure.  My plants under this name were supposedly collected in Trinidad by Richard Sheffer many years ago but the plants do not conform to all the characters of the description in Dr. Croat's revision of section Pachyneurium. This species is rather plastic from the description and I would accept the opinion of Dr. Croat, Joep Moonen, and David Scherberich, who have these species and have seen them in habitat." Despite common misconceptions, species within the Neotropical 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.  Also my sincere thanks to Emily Colletti who is the chief aroid greenhouse keeper at the Missouri Botanical Garden in St. Louis, MO for her assistance in photographing a specimen of Anthuiurm jenmanii in the garden's collection 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/ For eco-tour information contact Joep Moonen at EmeraldJungleVillage@wanadoo.fr Additional photographs by botanist David Scherberich can be seen here:  http://www.aroidpictures.fr/GENRES/anthuriuma-l.html   Aroid Pollination!  As it occurs in nature and by any horticulturist Join the International Aroid Society:  http://www.exoticrainforest.com/Join%20IAS.html Need more information on Anthurium species?  Click this link.