Nepenthes bokorensis
Encyclopedia
Nepenthes bokorensis is a tropical pitcher plant
endemic to Cambodia
. It is known from Mount Bokor (also Phnom Bokor or Bokor Hill) in the south of the country, and an as yet undetermined specimen suggests that it may also be present in other parts of the Dâmrei Mountains
of Kampot Province. The specific epithet bokorensis refers to both Mount Bokor and Bokor National Park.
Despite only being formally described
in 2009, N. bokorensis has been known since at least the early 20th century. The oldest known herbarium
specimens are three taken by French plant collector C. Geoffray on January 14, 1904. Two of these consist of lower pitchers with leaves, while the third comprises upper pitchers with leaves. All three specimens were collected from Popokvil falls, Mount Bokor, and are deposited at the Museum National d'Histoire Naturelle
in Paris
.
The next known collection of this species was made by J. E. Vidal in 1965. It consists of a plant with upper pitchers. Three years later, Marie Martin collected M. Martin 1231bis, which includes lower pitchers and female floral material. Further herbarium material, consisting of two rosette
plants, was collected by David Middleton and Meng Monyrak in 2001.
In July 2007, François Sockhom Mey found N. bokorensis on Mount Bokor during a field trip to southern Cambodia
. He posted photographs of the species on a number of online message boards the following month. Mey formally described
the species in the March 2009 issue of Carniflora Australis
, the journal of the Australasian Carnivorous Plant Society. M. Martin 1231bis, deposited at the Museum National d'Histoire Naturelle, was designated as the holotype
.
A specimen collected by Auguste Jean Baptiste Chevalier
in 1917 may also represent this species and if confirmed as such would increase the known range of N. bokorensis to include other parts of the Dâmrei Mountains
. Material deposited at Forest Herbarium, Bangkok
(BKF) and identified as N. thorelii
likely also belongs to N. bokorensis.
Nepenthes bokor, described by Martin Cheek
in June 2009, is a later synonym of N. bokorensis.
In August 2011, François Mey and Alastair Robinson
discovered two large new populations of N. bokorensis on the Mount Bokor massif
, which they called "Location B" and "Location C" (the original roadside population being "Location A").
and on lower parts of the plant, the stem is up to 0.9 cm thick and circular in cross section. On climbing parts, the stem is terete and measures up to 1 cm in diameter. Internode
s are around 3 cm long.
Leaves are sessile to sub-petiolate and coriaceous (leathery) in texture. The lamina or leaf blade is oblong to linear-lanceolate in shape and measures up to 35 cm in length by 8 cm in width. Its apex varies greatly, ranging from acute to obtuse and it may sometimes also be acuminate. The lamina is attenuate at the base, clasping the stem by around three-quarters of its circumference and rarely becoming decurrent. Three longitudinal veins are present on either side of the midrib. Pinnate veins originate obliquely from the midrib. Tendril
s are up to 18 cm long and 2 mm in diameter. Those produced on upper parts of the stem may be coiled.
Rosette and lower pitchers measure up to 20 cm in height by 6 cm in width. They are ovate in the basal third, before narrowing to become cylindrical or slightly infundibular towards the peristome
. A pair of fringed wings (≤15 mm wide) runs down the ventral surface of the pitcher cup. Fringe elements are up to 12 mm long. The pitcher mouth has an oblique insertion. The peristome is approximately cylindrical and may be up to 20 mm wide. It bears ribs (≤0.8 mm high) spaced up to 1 mm apart. The pitcher lid or operculum
is orbicular to broadly elliptic in shape, has a cordate base, and measures up to 7 cm in length by 6 cm in width. The underside of the lid lacks appendages, but bears numerous, densely-packed crater-like gland
s. Those concentrated along the midrib reach the greatest dimensions (≤0.5 mm in diameter), while the rest are much smaller (0.2 to 0.3 mm in diameter) and more sparsely distributed. A spur measuring up to 12 mm in length is inserted near the base of the lid. It is typically unbranched, but may also be bifurcate.
Upper pitchers exhibit great variability, but generally grow to 25 cm in height by 6 cm in width. They are infundibular throughout, becoming narrower in the basal portion. Wings are reduced to ribs in these aerial pitchers. The peristome is up to 17 mm wide and often somewhat flared at the margins. The peristome ribs are less developed than in lower pitchers, measuring only up to 0.4 mm in height, and spaced only up to 0.5 mm apart. The lid is similar to that found in terrestrial traps, although slightly smaller (up to 6 cm long by 5 cm wide) and often bearing a revolute margin. Other parts of upper pitchers are similar to their lower counterparts.
Nepenthes bokorensis has a racemose
inflorescence
measuring up to 100 cm in length. It bears up to 80 flowers borne on one-flowered pedicels
(≤9 mm long), or rarely two-flowered partial peduncles
. In male plants, the peduncle reaches 70 cm and the rachis
30 cm, while female plants produce a rachis up to 20 cm long. Tepal
s are orbicular to elliptic, ranging in length from 2 mm in male flowers to 4 mm in female flowers. The former have androphores up to 2 mm long, while the latter bear ovaries
around 4 mm long. Fruit are typically 10 to 25 mm long and each contain 50 to 100 fusiform seeds measuring around 7 mm in length.
All vegetative and floral parts of N. bokorensis bear an indumentum
of silvery or brownish hairs up to 1 mm long. In some places this covering may be reduced, giving an almost glabrous appearance.
It is not certain whether N. bokorensis produces a well-developed rootstock like other Indochinese
species, but observations of cultivated plants suggest that this is likely to be the case.
Nepenthes bokorensis is known with certainty only from the Mount Bokor massif in Bokor National Park, Kampot Province, Cambodia
, where it has an altitudinal distribution of 800–1080 m above sea level. Three populations are known from the mountain. An as yet undetermined specimen (Aug. Chevalier 36411) suggests that the species may also be present in other parts of the Dâmrei Mountains
.
The typical habitat of this species is seasonally dry upland scrub
. It also grows in stunted lower montane forest under sparse tree cover. Plants growing in exposed sites under direct sunlight are very stunted and often flower when less than 60 cm tall. The species attains much greater heights under the shade of surrounding vegetation. Nepenthes bokorensis is not known to grow with any other Nepenthes and no natural hybrids involving it have been recorded.
In open areas, N. bokorensis is sometimes sympatric
with other carnivorous plant
s, including sundew
s and bladderwort
s. The N. bokorensis plants found by François Mey in 2007 grew alongside a crimson form of Drosera peltata, but this population was destroyed by the time of the author's return in 2009. Drosera peltata still grows sympatrically with N. bokorensis at "Location C", a massive clearing discovered in 2011 on the Bokor plateau. The D. peltata plants at this site range in colour from yellowish-green to red and frequently exceed 30 cm in height. Nepenthes bokorensis also shares this habitat with another sundew—D. burmannii
—as well as with various grasses, stunded shrubs, and lithophytic
orchids. Local bladderwort species include U. bifida
, U. odorata
, U. minutissima
, U. striatula
, U. subulata
, and U. uliginosa
.
On Mount Bokor, the species grows on sand
y, acid
ic soils. The substrate
has a pH
of 4.6 according to the herbarium label of Middleton & Monyrak 589.
rates worldwide. Despite this, the habitat of N. bokorensis remained relatively undisturbed until 2009, lying as it did within the boundaries of Bokor National Park. At the time, François Mey assessed the conservation status
of N. bokorensis as "potentially vulnerable" based on the IUCN criteria, citing increasing tourism
and land development
as potential threats (Mount Bokor had been leased for private development by the government of Cambodia). Habitat loss accelerated rapidly in the following two years as work on the massive "Bokor City" project began in earnest. As of 2011, both the type population and the two newly discovered sites are threatened by the ongoing development.
s. This is reflected in the local Khmer
name for the plant, ampuong sramoch, which means "ants' pithole". This name is not specific to N. bokorensis but refers to Nepenthes in general, and is used in Kampot Province and the town of Pursat
.
The pitcher fluid of this species is strongly acid
ic; the label on the herbarium specimen Middleton & Monyrak 589 states that it has a pH
of 2.7.
pitcher plants, particularly N. kampotiana
, N. smilesii
, and N. thorelii
. It can be distinguished from all three on the basis of its wider, more oblong-shaped lamina and occasional two-flowered partial peduncles
.
The indumentum
of N. bokorensis is also distinctive, and distinguishes it from N. kampotiana, which typically has glabrous leaves. Compared to N. smilesii, N. bokorensis has more robust and colourful pitchers with a broader peristome
and longer tendril
s. The species differs from the enigmatic N. thorelii in several aspects of vegetative morphology. Firstly, the lamina of N. bokorensis is sessile to sub-petiolate and only slightly decurrent down the stem, if at all. In comparison, N. thorelii has an amplexicaul leaf attachment and the base of the lamina is decurrent into two wings that extend up to 2.5 cm down the stem. In addition, N. thorelii has wholly ovoid lower pitchers, whereas those of N. bokorensis are only ovate in the basal third, becoming cylindrical above.
Nepenthes bokorensis also appears to be closely related to N. kerrii of Thailand
. It can be distinguished from this species on the basis of its laminae, which are linear to lanceolate as opposed to obovate in the latter. It also differs in having a variable indumentum covering all vegetative and floral parts. In contrast, the indumentum of N. kerrii is restricted to the leaf axils. The androphore of N. kerrii is also considerably shorter than that of N. bokorensis.
Pitcher plant
Pitcher plants are carnivorous plants whose prey-trapping mechanism features a deep cavity filled with liquid known as a pitfall trap. It has been widely assumed that the various sorts of pitfall trap evolved from rolled leaves, with selection pressure favouring more deeply cupped leaves over...
endemic to Cambodia
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
. It is known from Mount Bokor (also Phnom Bokor or Bokor Hill) in the south of the country, and an as yet undetermined specimen suggests that it may also be present in other parts of the Dâmrei Mountains
Dâmrei Mountains
The Dâmrei Mountains, literally the "Elephant Mountains", are a mountain range situated in the southwest of Cambodia.-Description:These mountains are an offshoot of the Krâvanh or Cardamom Mountains, but occupy a much smaller area. The highest elevation is Phnom Bokor at 1,081 meters above...
of Kampot Province. The specific epithet bokorensis refers to both Mount Bokor and Bokor National Park.
Botanical history
Species description
A species description or type description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species which have been described previously, or are...
in 2009, N. bokorensis has been known since at least the early 20th century. The oldest known herbarium
Herbarium
In botany, a herbarium – sometimes known by the Anglicized term herbar – is a collection of preserved plant specimens. These specimens may be whole plants or plant parts: these will usually be in a dried form, mounted on a sheet, but depending upon the material may also be kept in...
specimens are three taken by French plant collector C. Geoffray on January 14, 1904. Two of these consist of lower pitchers with leaves, while the third comprises upper pitchers with leaves. All three specimens were collected from Popokvil falls, Mount Bokor, and are deposited at the Museum National d'Histoire Naturelle
Muséum national d'histoire naturelle
The Muséum national d'Histoire naturelle is the National Museum of Natural History in Paris, France.- History :The museum was formally founded on 10 June 1793, during the French Revolution...
in Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
.
The next known collection of this species was made by J. E. Vidal in 1965. It consists of a plant with upper pitchers. Three years later, Marie Martin collected M. Martin 1231bis, which includes lower pitchers and female floral material. Further herbarium material, consisting of two rosette
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
plants, was collected by David Middleton and Meng Monyrak in 2001.
In July 2007, François Sockhom Mey found N. bokorensis on Mount Bokor during a field trip to southern Cambodia
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
. He posted photographs of the species on a number of online message boards the following month. Mey formally described
Species description
A species description or type description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species which have been described previously, or are...
the species in the March 2009 issue of Carniflora Australis
Carniflora Australis
Carniflora Australis is a biannual English-language periodical and the official publication of the Australasian Carnivorous Plant Society. Typical articles include matters of horticultural interest, field reports, and scientific studies. The journal was established in March 2003...
, the journal of the Australasian Carnivorous Plant Society. M. Martin 1231bis, deposited at the Museum National d'Histoire Naturelle, was designated as the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
.
A specimen collected by Auguste Jean Baptiste Chevalier
Auguste Jean Baptiste Chevalier
Auguste Jean Baptiste Chevalier was a French botanist, taxonomist, and explorer of tropical Africa, especially of French colonial empire Africa and Côte d'Ivoire. He also explored and collected plants in South America and tropical Asia...
in 1917 may also represent this species and if confirmed as such would increase the known range of N. bokorensis to include other parts of the Dâmrei Mountains
Dâmrei Mountains
The Dâmrei Mountains, literally the "Elephant Mountains", are a mountain range situated in the southwest of Cambodia.-Description:These mountains are an offshoot of the Krâvanh or Cardamom Mountains, but occupy a much smaller area. The highest elevation is Phnom Bokor at 1,081 meters above...
. Material deposited at Forest Herbarium, Bangkok
Bangkok
Bangkok is the capital and largest urban area city in Thailand. It is known in Thai as Krung Thep Maha Nakhon or simply Krung Thep , meaning "city of angels." The full name of Bangkok is Krung Thep Mahanakhon Amon Rattanakosin Mahintharayutthaya Mahadilok Phop Noppharat Ratchathani Burirom...
(BKF) and identified as N. thorelii
Nepenthes thorelii
Nepenthes thorelii is a tropical pitcher plant endemic to Indochina. Very little is known about N. thorelii and it is unlikely to have entered cultivation, although various other taxa are often mislabelled as this species in the plant trade...
likely also belongs to N. bokorensis.
Nepenthes bokor, described by Martin Cheek
Martin Cheek
Dr. Martin Roy Cheek is a taxonomist and botanist specialising in the carnivorous plant genus Nepenthes.-Research:Cheek has described several new Nepenthes species, mostly with Matthew Jebb, including: N. argentii, N. aristolochioides, N. danseri, N. diatas,...
in June 2009, is a later synonym of N. bokorensis.
In August 2011, François Mey and Alastair Robinson
Alastair Robinson
Dr. Alastair S. Robinson is a British-American taxonomist and field botanist specialising in the carnivorous plant genus Nepenthes...
discovered two large new populations of N. bokorensis on the Mount Bokor massif
Massif
In geology, a massif is a section of a planet's crust that is demarcated by faults or flexures. In the movement of the crust, a massif tends to retain its internal structure while being displaced as a whole...
, which they called "Location B" and "Location C" (the original roadside population being "Location A").
Description
Nepenthes bokorensis is a climbing plant, attaining a height of up to 7 m. In rosettesRosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
and on lower parts of the plant, the stem is up to 0.9 cm thick and circular in cross section. On climbing parts, the stem is terete and measures up to 1 cm in diameter. Internode
Plant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...
s are around 3 cm long.
Tendril
In botany, a tendril is a specialized stem, leaf or petiole with a threadlike shape that is used by climbing plants for support, attachment and cellular invasion by parasitic plants, generally by twining around suitable hosts. They do not have a lamina or blade, but they can photosynthesize...
s are up to 18 cm long and 2 mm in diameter. Those produced on upper parts of the stem may be coiled.
Peristome
The word peristome is derived from the Greek peri, meaning 'around' or 'about', and stoma, 'mouth'. It is a term used to describe various anatomical features that surround an opening to an organ or structure. The term is used in plants and invertebrate animals, such as in describing the shells of...
. A pair of fringed wings (≤15 mm wide) runs down the ventral surface of the pitcher cup. Fringe elements are up to 12 mm long. The pitcher mouth has an oblique insertion. The peristome is approximately cylindrical and may be up to 20 mm wide. It bears ribs (≤0.8 mm high) spaced up to 1 mm apart. The pitcher lid or operculum
Operculum (botany)
An operculum, in botany, is a term generally used to describe a structure within a plant, moss, or fungus acting as a cap, flap, or lid. In plants, it may also be called a bud cap.Examples of structures identified as opercula include:...
is orbicular to broadly elliptic in shape, has a cordate base, and measures up to 7 cm in length by 6 cm in width. The underside of the lid lacks appendages, but bears numerous, densely-packed crater-like gland
Gland
A gland is an organ in an animal's body that synthesizes a substance for release of substances such as hormones or breast milk, often into the bloodstream or into cavities inside the body or its outer surface .- Types :...
s. Those concentrated along the midrib reach the greatest dimensions (≤0.5 mm in diameter), while the rest are much smaller (0.2 to 0.3 mm in diameter) and more sparsely distributed. A spur measuring up to 12 mm in length is inserted near the base of the lid. It is typically unbranched, but may also be bifurcate.
Upper pitchers exhibit great variability, but generally grow to 25 cm in height by 6 cm in width. They are infundibular throughout, becoming narrower in the basal portion. Wings are reduced to ribs in these aerial pitchers. The peristome is up to 17 mm wide and often somewhat flared at the margins. The peristome ribs are less developed than in lower pitchers, measuring only up to 0.4 mm in height, and spaced only up to 0.5 mm apart. The lid is similar to that found in terrestrial traps, although slightly smaller (up to 6 cm long by 5 cm wide) and often bearing a revolute margin. Other parts of upper pitchers are similar to their lower counterparts.
Nepenthes bokorensis has a racemose
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
measuring up to 100 cm in length. It bears up to 80 flowers borne on one-flowered pedicels
Pedicel (botany)
A pedicel is a stem that attaches single flowers to the main stem of the inflorescence. It is the branches or stalks that hold each flower in an inflorescence that contains more than one flower....
(≤9 mm long), or rarely two-flowered partial peduncles
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
. In male plants, the peduncle reaches 70 cm and the rachis
Rachis
Rachis is a biological term for a main axis or "shaft".-In zoology:In vertebrates a rachis can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the rachis usually form the supporting axis of the body and is then called the spine or vertebral column...
30 cm, while female plants produce a rachis up to 20 cm long. Tepal
Tepal
Tepals are elements of the perianth, or outer part of a flower, which include the petals or sepals. The term tepal is more often applied specifically when all segments of the perianth are of similar shape and color, or undifferentiated, which is called perigone...
s are orbicular to elliptic, ranging in length from 2 mm in male flowers to 4 mm in female flowers. The former have androphores up to 2 mm long, while the latter bear ovaries
Ovary
The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in anatomically female individuals are analogous to testes in anatomically male individuals, in that they are both gonads and endocrine glands.-Human anatomy:Ovaries...
around 4 mm long. Fruit are typically 10 to 25 mm long and each contain 50 to 100 fusiform seeds measuring around 7 mm in length.
All vegetative and floral parts of N. bokorensis bear an indumentum
Indumentum
The indumentum is a covering of fine hairs or bristles on a plant or insect.In plants, the indumentum types are:*pubescent*hirsute*pilose*villous*tomentose*stellate*scabrous*scurfy...
of silvery or brownish hairs up to 1 mm long. In some places this covering may be reduced, giving an almost glabrous appearance.
It is not certain whether N. bokorensis produces a well-developed rootstock like other Indochinese
Indochina
The Indochinese peninsula, is a region in Southeast Asia. It lies roughly southwest of China, and east of India. The name has its origins in the French, Indochine, as a combination of the names of "China" and "India", and was adopted when French colonizers in Vietnam began expanding their territory...
species, but observations of cultivated plants suggest that this is likely to be the case.
Ecology
Cambodia
Cambodia , officially known as the Kingdom of Cambodia, is a country located in the southern portion of the Indochina Peninsula in Southeast Asia...
, where it has an altitudinal distribution of 800–1080 m above sea level. Three populations are known from the mountain. An as yet undetermined specimen (Aug. Chevalier 36411) suggests that the species may also be present in other parts of the Dâmrei Mountains
Dâmrei Mountains
The Dâmrei Mountains, literally the "Elephant Mountains", are a mountain range situated in the southwest of Cambodia.-Description:These mountains are an offshoot of the Krâvanh or Cardamom Mountains, but occupy a much smaller area. The highest elevation is Phnom Bokor at 1,081 meters above...
.
The typical habitat of this species is seasonally dry upland scrub
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
. It also grows in stunted lower montane forest under sparse tree cover. Plants growing in exposed sites under direct sunlight are very stunted and often flower when less than 60 cm tall. The species attains much greater heights under the shade of surrounding vegetation. Nepenthes bokorensis is not known to grow with any other Nepenthes and no natural hybrids involving it have been recorded.
In open areas, N. bokorensis is sometimes sympatric
Sympatry
In biology, two species or populations are considered sympatric when they exist in the same geographic area and thus regularly encounter one another. An initially-interbreeding population that splits into two or more distinct species sharing a common range exemplifies sympatric speciation...
with other carnivorous plant
Carnivorous plant
Carnivorous plants are plants that derive some or most of their nutrients from trapping and consuming animals or protozoans, typically insects and other arthropods. Carnivorous plants appear adapted to grow in places where the soil is thin or poor in nutrients, especially nitrogen, such as acidic...
s, including sundew
Sundew
Drosera, commonly known as the sundews, comprise one of the largest genera of carnivorous plants, with at least 194 species. These members of the family Droseraceae lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surface. The insects are used to supplement...
s and bladderwort
Bladderwort
Utricularia, commonly and collectively called the bladderworts, is a genus of carnivorous plants consisting of approximately 233 species . They occur in fresh water and wet soil as terrestrial or aquatic species across every continent except Antarctica...
s. The N. bokorensis plants found by François Mey in 2007 grew alongside a crimson form of Drosera peltata, but this population was destroyed by the time of the author's return in 2009. Drosera peltata still grows sympatrically with N. bokorensis at "Location C", a massive clearing discovered in 2011 on the Bokor plateau. The D. peltata plants at this site range in colour from yellowish-green to red and frequently exceed 30 cm in height. Nepenthes bokorensis also shares this habitat with another sundew—D. burmannii
Drosera burmannii
Drosera burmannii, the tropical sundew, is a small, compact species in the carnivorous plant genus Drosera. It normally spans only in diameter. It is one of the fastest trapping sundews as well, and its leaves can curl around an insect in only a few seconds, compared to the minutes or hours it...
—as well as with various grasses, stunded shrubs, and lithophytic
Lithophyte
Lithophytes are a type of plant that grows in or on rocks. Lithophytes feed off moss, nutrients in rain water, litter, and even their own dead tissue....
orchids. Local bladderwort species include U. bifida
Utricularia bifida
Utricularia bifida is a small annual carnivorous plant that belongs to the genus Utricularia. It is native to Asia and Oceania and can be found in Australia, Bangladesh, Burma, Cambodia, China, Guam, India, Indonesia, Japan, Korea, Laos, Malaysia, Nepal, New Guinea, Palau, the Philippines, Sri...
, U. odorata
Utricularia odorata
Utricularia odorata is a medium-sized, probably perennial carnivorous plant that belongs to the genus Utricularia. It is native to southeastern Asia and northern Australia . U. odorata grows as a terrestrial plant in wet grasslands at low altitudes. It was originally described by François...
, U. minutissima
Utricularia minutissima
Utricularia minutissima is a small or very small terrestrial carnivorous plant that belongs to the genus Utricularia. U. minutissima is native to Asia and Australia...
, U. striatula
Utricularia striatula
Utricularia striatula is a small carnivorous plant that belongs to the genus Utricularia. It is widespread from tropical Africa to New Guinea. U. striatula grows as a lithophyte or epiphyte on wet rocks or tree trunks at altitudes from near sea level to . It was originally described by James...
, U. subulata
Utricularia subulata
Utricularia subulata, the zigzag bladderwort, is a small annual, terrestrial carnivorous plant that belongs to the genus Utricularia . It is the most widely distributed species in the genus, being almost pantropical....
, and U. uliginosa
Utricularia uliginosa
Utricularia uliginosa, the Asian bladderwort, is a small annual carnivorous plant that belongs to the genus Utricularia. It is native to Southeast Asia , Oceania , and Australia Utricularia uliginosa, the Asian bladderwort, is a small annual carnivorous plant that belongs to the genus Utricularia....
.
On Mount Bokor, the species grows on sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
y, acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
ic soils. The substrate
Substrate (biology)
In biology a substrate is the surface a plant or animal lives upon and grows on. A substrate can include biotic or abiotic materials and animals. For example, encrusting algae that lives on a rock can be substrate for another animal that lives on top of the algae. See also substrate .-External...
has a pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
of 4.6 according to the herbarium label of Middleton & Monyrak 589.
Conservation
Cambodia ranks among the countries with the highest deforestationDeforestation
Deforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use....
rates worldwide. Despite this, the habitat of N. bokorensis remained relatively undisturbed until 2009, lying as it did within the boundaries of Bokor National Park. At the time, François Mey assessed the conservation status
Conservation status
The conservation status of a group of organisms indicates whether the group is still extant and how likely the group is to become extinct in the near future...
of N. bokorensis as "potentially vulnerable" based on the IUCN criteria, citing increasing tourism
Tourism
Tourism is travel for recreational, leisure or business purposes. The World Tourism Organization defines tourists as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes".Tourism has become a...
and land development
Land development
Land development refers to altering the landscape in any number of ways such as:* changing landforms from a natural or semi-natural state for a purpose such as agriculture or housing...
as potential threats (Mount Bokor had been leased for private development by the government of Cambodia). Habitat loss accelerated rapidly in the following two years as work on the massive "Bokor City" project began in earnest. As of 2011, both the type population and the two newly discovered sites are threatened by the ongoing development.
Carnivory
The prey assemblage of N. bokorensis appears to consist primarily of antAnt
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s. This is reflected in the local Khmer
Khmer language
Khmer , or Cambodian, is the language of the Khmer people and the official language of Cambodia. It is the second most widely spoken Austroasiatic language , with speakers in the tens of millions. Khmer has been considerably influenced by Sanskrit and Pali, especially in the royal and religious...
name for the plant, ampuong sramoch, which means "ants' pithole". This name is not specific to N. bokorensis but refers to Nepenthes in general, and is used in Kampot Province and the town of Pursat
Pursat
Pursat is the capital of Pursat Province, Cambodia. Its name derived from a type of tree.- Notes :...
.
The pitcher fluid of this species is strongly acid
Acid
An acid is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red...
ic; the label on the herbarium specimen Middleton & Monyrak 589 states that it has a pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
of 2.7.
Related species
Nepenthes bokorensis is most closely allied to several other IndochineseIndochina
The Indochinese peninsula, is a region in Southeast Asia. It lies roughly southwest of China, and east of India. The name has its origins in the French, Indochine, as a combination of the names of "China" and "India", and was adopted when French colonizers in Vietnam began expanding their territory...
pitcher plants, particularly N. kampotiana
Nepenthes kampotiana
Nepenthes kampotiana is a tropical pitcher plant native to southern Cambodia, eastern Thailand, and western Vietnam. The specific epithet kampotiana refers to the Cambodian city of Kampot, close to which the first specimens of this species were collected.This species is closely related to...
, N. smilesii
Nepenthes smilesii
Nepenthes smilesii is a tropical pitcher plant native to northeastern Thailand, southern Laos, Cambodia, and western Vietnam. Nepenthes smilesii can tolerate an extended dry season and is most common in open, sandy savannah and grassland....
, and N. thorelii
Nepenthes thorelii
Nepenthes thorelii is a tropical pitcher plant endemic to Indochina. Very little is known about N. thorelii and it is unlikely to have entered cultivation, although various other taxa are often mislabelled as this species in the plant trade...
. It can be distinguished from all three on the basis of its wider, more oblong-shaped lamina and occasional two-flowered partial peduncles
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...
.
Indumentum
The indumentum is a covering of fine hairs or bristles on a plant or insect.In plants, the indumentum types are:*pubescent*hirsute*pilose*villous*tomentose*stellate*scabrous*scurfy...
of N. bokorensis is also distinctive, and distinguishes it from N. kampotiana, which typically has glabrous leaves. Compared to N. smilesii, N. bokorensis has more robust and colourful pitchers with a broader peristome
Peristome
The word peristome is derived from the Greek peri, meaning 'around' or 'about', and stoma, 'mouth'. It is a term used to describe various anatomical features that surround an opening to an organ or structure. The term is used in plants and invertebrate animals, such as in describing the shells of...
and longer tendril
Tendril
In botany, a tendril is a specialized stem, leaf or petiole with a threadlike shape that is used by climbing plants for support, attachment and cellular invasion by parasitic plants, generally by twining around suitable hosts. They do not have a lamina or blade, but they can photosynthesize...
s. The species differs from the enigmatic N. thorelii in several aspects of vegetative morphology. Firstly, the lamina of N. bokorensis is sessile to sub-petiolate and only slightly decurrent down the stem, if at all. In comparison, N. thorelii has an amplexicaul leaf attachment and the base of the lamina is decurrent into two wings that extend up to 2.5 cm down the stem. In addition, N. thorelii has wholly ovoid lower pitchers, whereas those of N. bokorensis are only ovate in the basal third, becoming cylindrical above.
Nepenthes bokorensis also appears to be closely related to N. kerrii of Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
. It can be distinguished from this species on the basis of its laminae, which are linear to lanceolate as opposed to obovate in the latter. It also differs in having a variable indumentum covering all vegetative and floral parts. In contrast, the indumentum of N. kerrii is restricted to the leaf axils. The androphore of N. kerrii is also considerably shorter than that of N. bokorensis.
External links
- Photographs of N. bokorensis at the Carnivorous Plant Photofinder
- Nepenthes of Indochina by Marcello CatalanoMarcello CatalanoMarcello Catalano is an Italian naturalist and author specializing in carnivorous plants. As a result of this interest, which began in 1985, Catalano founded the Italian Carnivorous Plant Society and its quarterly magazine, AIPC News , at the end of the 1990s.From 2000 to 2004, he...