Nepenthes fusca
Encyclopedia
Nepenthes fusca or the Dusky Pitcher-Plant, is a tropical pitcher plant
endemic to Borneo
. It is found throughout a wide altitudinal range
and is almost always epiphytic in nature, primarily growing in mossy forest.
The specific epithet fusca is derived from the Latin
word fuscus, meaning "dark brown" or "dusky", and refers to the colour of the pitchers.
on October 12, 1925, from Mount Kemul
in East Kalimantan
, at an elevation of 1500 m. It was discovered during an expedition to central Borneo by the Forest Research Institute of Bogor
(then known as Buitenzorg), on which Endert also made the only known collection of N. mollis
. The N. fusca specimen, designated as Endert 3955, includes male floral material and is deposited at Herbarium Bogoriense (BO), the herbarium
of the Bogor Botanical Gardens
. Endert wrote about this pitcher plant in a detailed 1927 account of the expedition, although he misidentified it as N. veitchii
.
Nepenthes fusca was formally described
in 1928 by Dutch
botanist B. H. Danser
in his seminal monograph "The Nepenthaceae of the Netherlands Indies
". Danser based his description solely on Endert 3955, citing no other specimens. He wrote of N. fusca:
Botanist Jan Schlauer has noted differences between the type specimen of N. fusca and Sabah plants referred to this species, even interpreting plants illustrated in Kurata's Nepenthes of Mount Kinabalu
as representing N. stenophylla
(as distinct from N. fallax). Matthew Jebb
does not consider these differences significant enough to merit distinction at the species level. He suggests that the type specimen consists of intermediate lower and upper pitchers as opposed to true forms of either, making them appear atypical.
Much of this taxonomic uncertainty stems from the fact that N. fusca has not been recollected from the type locality and many similar plants have been lumped under this taxon. Matthew Jebb
and Martin Cheek
attempted to resolve this confusion in their 1997 monograph by interpreting N. fusca as a widespread and variable species.
of N. fusca have been described:
Both were originally coined by J. H. Adam
and C. C. Wilcock
and subsequently published in Jebb and Cheek's 1997 monograph, "A skeletal revision of Nepenthes (Nepenthaceae)
". As these names were published without an adequate description, they are both considered nomina nuda
. The former is based on Chai 35939, a specimen collected from Mount Apo. Schlauer considers it synonymous with N. fallax, a taxon that is in turn considered conspecific with N. stenophylla
by most authors.
Nepenthes fusca subsp. kostermansiana is thought to be assigned to the correct species. The type specimen (Kostermans 21495) was collected on October 25, 1963, from Kelai River
, Mount Njapa, Berau. It is deposited at the National Herbarium of the Netherlands
in Leiden.
Nepenthes maxima
, a species native to Sulawesi
, New Guinea
, and the Maluku Islands
, was once thought to extend to Borneo as well. Some authors even wrote that it was widespread on the island. This confusion stemmed from the likeness of N. fusca and N. maxima, and from apparently mislabelled seeds collected by Charles Curtis
. Curtis was not meticulous in recording where he located individual plants; although it was originally believed that he collected N. curtisii (now considered synonymous with N. maxima) in Borneo, botanist Charles Clarke
points out that he also visited Sulawesi
on the same trip, and N. maxima is common there.
Matthew Jebb
and Martin Cheek
resolved this confusion in their 1997 monograph by referring a number of Bornean plants identified as N. maxima to N. fusca, thereby excluding the former from the island.
and C. C. Wilcock
described Nepenthes curtisii subsp. zakriana. Ten years later, Adam and Hafiza A. Hamid elevated it to species status as Nepenthes zakriana (n, not /ˌzækriˈænə/). The authors described the taxon
as a Sabah
endemic growing at elevations of 1200 to 1500 m.
Adam and Hafiza wrote that N. zakriana "consistently differed from Nepenthes fusca by prominent raised midribs, extended beyond apex forming an apical glandular appendages on lower lid surface of both upper and lower pitchers; and basal half portion of the midrib developed in nail-shaped glandular crest". However, a number of authors soon voiced their doubts as to whether N. zakriana merited species status and in Pitcher Plants of Borneo by Anthea Phillipps
, Anthony Lamb
, and Ch'ien Lee
, these features were considered to fall within the natural variability of N. fusca.
, Charles Clarke
lists the undescribed taxon
"Nepenthes sp. A", which has been recorded from Gunung Mulu National Park
in Sarawak
. It bears a close resemblance to N. fusca and may be conspecific with it, although its colouration is unusual for the species. The pitchers of this plant match J. H. Adam
and C. C. Wilcock
's description of N. faizaliana
, but the latter is now known to have a round lid (as opposed to narrowly triangular in N. fusca and "Nepenthes sp. A"), suggesting that these two taxa are not closely related. Clarke proposes that this taxon might fall under Jebb and Cheek's more inclusive concept of N. fusca, but retains it as an undescribed species because it remains poorly known.
"Nepenthes sp. A" was first illustrated in a 1988 article by Anthea Phillipps
and Anthony Lamb
, where it was considered an undescribed species.
Nepenthes fusca is a climbing plant. The stem may attain a length of 10 m and is up to 8 mm in diameter. Internodes are circular in cross section and up to 7 cm long.
The leaves of this species are petiolate and coriaceous in texture. The lamina or leaf blade is obovate-oblong in shape and measures up to 15 cm in length by 6 cm in width. Its apex is acute to obtuse and may even be slightly peltate. The base of the lamina is gradually attenuate towards the petiole
. The petiole (≤4 cm long) is grooved lengthwise and bears a pair of narrow wings that form a semi-amplexicaul sheath around the stem. Up to 3 longitudinal veins are present on either side of the midrib, although they are indistinct. Pinnate veins are numerous. Tendril
s measure up to 5 cm in length.
Rosette and lower pitchers are cylindrical throughout. They usually grow to 20 cm in height by 4 cm in width, although exceptional specimens up to 28 cm have been recorded. A pair of fringed wings (≤5 mm wide) runs down the ventral surface of the pitcher and bears fringe elements measuring up to 10 mm and spaced 6 mm apart. The gland
ular region is restricted to the lower portion of the pitcher's inner surface. The glands are small, overarched, and occur at a density of 600 to 650 per square centimetre. The pitcher mouth is positioned horizontally at the front, becoming elongated into a neck at the rear. The peristome
is flattened and expanded (≤12 mm wide), but bears only indistinct teeth (≤0.3 mm long). The pitcher lid or operculum
is very narrowly ovate in shape and has a distinctive basal crest on its lower surface. An unbranched spur measuring up to 10 mm in length is inserted near the base of the lid.
Upper pitchers differ markedly in shape, being narrowly infundibular in the lower two-thirds and becoming widely infundibular above. They are similar in size to their lower counterparts, typically measuring up to 18 cm, with some larger forms reaching 26 cm. The tiny digestive glands are overarched and number 1500 to 2000 per square centimetre. The pitcher lid is very narrowly triangular with the margins and apex curved downwards. In aerial pitchers, the wings are reduced to ribs.
Nepenthes fusca produces a compact racemose
inflorescence
. The peduncle
is up to 6 cm long, while the rachis
is not known to exceed 10 cm. Partial peduncles are one- or two-flowered, up to 8 mm long, and lack a bract
. Sepal
s are elliptic and up to 4 mm long. A study of 120 pollen
samples taken from the type specimen (Endert 3955) found the mean pollen diameter to be 34.8 μm
(SE
= 0.6; CV
= 9.1%).
Developing parts of the plant bear an indumentum
of long, brown hairs. However, most of these disappear during the normal course of development, and mature parts only have a sparse covering of short, brown hairs.
Nepenthes fusca is endemic to Borneo
, where its range stretches from Central Kalimantan
to northwestern Sabah
. It has been recorded from Brunei
, Indonesia
(Kalimantan
), and Malaysia (Sabah
and Sarawak
). The species has a wide altitudinal distribution and is typically found at elevations of 1200 to 2500 m above sea level. However, N. fusca has occasionally been reported from lowland hills down to 600 m and in Sarawak it has been found at only 300 m in hill forest.
Nepenthes fusca is most commonly found as an epiphyte
in shady mossy forest on ridge tops, where it may grow 10 to 15 m off the ground. This makes it particularly difficult to find and often the only evidence of its presence are dead pitchers that have fallen to the forest floor. In this respect, it can be considered the "ecological equivalent" of N. bongso
from Sumatra
. More rarely, N. fusca grows terrestrially in exposed sites near montane forest or along logging roads. It is often sympatric with species such as N. reinwardtiana
, N. stenophylla
, and N. tentaculata
, and natural hybrids with all of these have been recorded.
The species has been recorded from numerous mountains across Borneo. It can be found at several sites on Mount Kinabalu
, including Kambarangoh
, the Marai Parai
plateau
, the mountain's East Ridge, and the Bambangan River at around 1500 m. It also grows on the side of the road connecting the park headquarters and the power station, despite being frequently cut back as part of road maintenance. This is one of the few places where N. fusca may be easily seen by visitors. These roadside plants were greatly affected by the El Niño climatic phenomenon of 1997 to 1998. The resulting dry period severely depleted the population, such that "almost all the plants were destroyed". Nearby plants from more sheltered locations fared better and appeared to have recovered by the following year. A number of N. fusca plants have also been transplanted to the Mesilau nature trail
.
Nepenthes fusca can be viewed along the road leading to the disused Mamut copper mine, where it is sympatric with N. macrovulgaris
, N. stenophylla
, and the natural hybrid N. fusca × N. stenophylla; N. burbidgeae
grows a short distance away.
The species also occurs on nearby Mount Tambuyukon
. On Mount Trus Madi
, N. fusca has been found at an elevation of almost 1800 m, growing as an epiphyte in Eleocarpus trees. An atypical yellow form grows on Mount Lumarku
in Sabah. On Mount Mulu
in Sarawak, N. fusca grows below 1200 m, such that its distribution does not overlap with that of two other epiphytes: N. vogelii
, which grows from 1200 to 1500 m, and N. hurrelliana
, which occurs above 1500 m. Other notable locations include Mount Alab (the highest peak of the Crocker Range
), the Kimanis
–Keningau
Road that runs through the Crocker Range, Mount Njapa (where it grows at 1000 m), and the summit area of Mount Apo Dari (1500 m).
In the Hose Mountains
of central Sarawak, N. fusca is typically found growing as an epiphyte in lower montane forest at 700–1200 m. It is also an uncommon inhabitant of roadside embankments there.
Nepenthes fusca is classified as Vulnerable
on the 2006 IUCN Red List of Threatened Species
, based on an assessment carried out in 2000. This agrees with an informal assessment made by Charles Clarke
in 1997, who also classified the species as Vulnerable based on the IUCN
criteria. However, Clarke noted that since substantial populations of N. fusca lie within the boundaries of national park
s, they "are unlikely to become threatened in the foreseeable future". Taking this into account, he suggested a revised assessment of Conservation Dependent
. However, it differs from the assessment by the World Conservation Monitoring Centre
, which classified N. fusca as "not threatened", its lowest conservation status.
, N. platychila
, N. stenophylla
, and N. vogelii
. The enigmatic N. mollis
, which some authors have suggested is conspecific with N. hurrelliana, may also be closely allied.
The lower pitchers of N. hurrelliana are distinctive, but the upper ones bear a close resemblance to those of N. fusca. Of the Bornean pitcher plant
flora, only these two species have such a narrowly triangular lid. The upper pitchers of N. hurrelliana differ in having a horizontal mouth that rises abruptly into a long neck at the back and in having a hirsute basal crest on the underside of the lid.
Nepenthes hurrelliana is particularly similar to a form of N. fusca from the southern portion of the Crocker Range
in Sabah
. This form exhibits a wider peristome, longer neck, and a more triangular lid than most other examples of the species. However, the peristome is still not as well developed as in N. hurrelliana and the plant lacks the dense indumentum of the latter. Furthermore, N. hurrelliana differs in the distribution of nectar glands on the lower surface of its lid.
The first known collection of N. vogelii
, made in 1961, was labelled as N. fusca. In 1969, botanist Shigeo Kurata
examined this specimen and noted that it did not fall within the known variation exhibited by N. fusca. Nevertheless, the species remained undescribed until 2002. Nepenthes vogelii differs in having much smaller pitchers and lacking appendages on the underside of the lid. In addition, the lid of N. vogelii is broadly triangular as opposed to the narrowly triangular lid of N. fusca. The colour of the pitchers—light cream with dark speckles—is also distinctive.
Nepenthes faizaliana
also bears a resemblance to N. fusca. In their description of the former, J. H. Adam
and C. C. Wilcock
distinguished these taxa
on the basis of inflorescence structure, the size of the glandular region on the inner surface of upper pitchers, and the development and characteristics of the indumentum
. In addition, N. fusca differs in having a very narrow pitcher lid, as opposed to the orbicular lid of N. faizaliana.
Nepenthes platychila can be distinguished from N. fusca on the basis of its much wider peristome and lid, the latter lacking appendages on its lower surface. Nepenthes fusca is also thought to be closely related to Sulawesi
's N. eymae
, and N. maxima
, which is widespread in Sulawesi, New Guinea
, and the Maluku Islands
.
growth habit.
× N. fusca has been known since at least the early 1980s, when it was found during an expedition to Sabah.
(known as N. pilosa
at the time) by Charles Clarke
. However, Anthea Phillipps
, Anthony Lamb
, and Ch'ien Lee
differ in their interpretation, noting that the plant exhibits influences of N. fusca, such as a triangular lid and an elongated neck. They write that both N. fusca and N. lowii
are common in the summit area, whereas N. chaniana is rare. Another possible parent species, N. stenophylla
, is apparently absent from the site.
Nepenthes fusca × N. lowii was discovered by Rob Cantley
and Charles Clarke
on Bukit Batu Lawi
in Sarawak
. Clarke later found larger plants of this hybrid in the Crocker Range
of Sabah
, particularly near the summit of Mount Alab. The pitchers of N. fusca × N. lowii have a slight constriction in the middle and range in colour from green to dark purple throughout.
This hybrid differs from N. fusca in the presence of bristles on the underside of the lid. Conversely, it has a dense indumentum
on the stem and at the margins of the lamina, compared to the virtually glabrous stem and leaves of N. lowii. It also differs from N. lowii in having a more developed peristome
, which is circular in cross section. While lower pitchers of N. lowii have prominent teeth, those of N. fusca × N. lowii are indistinct. In addition, a glandular appendage is present on the underside of the lid, a trait inherited from N. fusca.
Nepenthes fusca × N. lowii is difficult to confuse with its putative parent species, but is somewhat similar to N. chaniana × N. veitchii
. The latter hybrid can be distinguished on the basis of its peristome, which is wider, more flared, and less cylindrical. In addition, this hybrid has a less ovate lid, which lacks the bristles characteristic of N. lowii, and a denser indumentum covering the stem and leaves.
has been recorded. N. naquiyuddinii is generally thought to be a heterotypic synonym of N. reinwardtiana, but may also represent this hybrid, as both putative parent species grow in close proximity to it.
, where it grows in lower montane forest. Both N. fusca and N. stenophylla
are common in this area. It has also been recorded from the Mamut copper mine. It more closely resembles N. stenophylla, but differs in the shape of the lid, which is more oval-shaped.
was discovered by Linus Gokusing near the summit of Mount Alab, where it grows in upper montane forest at elevations of around 1800 to 2000 m. It is sympatric with both parent species, which are abundant in the area.
, N. rajah
, and N. veitchii
have been recorded.
The pitchers of N. hurrelliana
are roughly intermediate in appearance between those of N. fusca and N. veitchii
. This has led to speculation regarding the lineage of this species, with a number of authors suggesting a possible hybridogenic origin. However, N. hurrelliana is distinct from the natural hybrid N. fusca × N. veitchii and most authors now regard it as a valid species.
Little information has been published on the growing requirements of N. fusca. In 2004, professional horticulturist Robert Sacilotto wrote an article for the Carnivorous Plant Newsletter
, summarising measured tolerances of several highland Nepenthes species based on experiments conducted between 1996 and 2001.
Sacilotto found N. fusca to be tolerant of a wide range of conditions; with the exception of plants not treated with fungicide
s, no test groups showed a survival rate
of less than 75%. Nepenthes fusca was found to tolerate temperatures in the range of 10 to 38 °C (50 to 100.4 F). A nighttime drop in temperature below 21 °C (69.8 °F) was necessary for good growth; plants that were not exposed to such a drop grew poorly and produced fewer pitchers. The experiments suggested that N. fusca grows best when relative humidity
is in the range of 65 to 90%.
The species seemed to do best in growing media with a high proportion of organic matter
(such as a mixture consisting of 10% peat moss chunks, 30% perlite
, and 60% of any combination of Sphagnum
moss
and fir
bark
). Soil with a slightly acid
ic pH
of 4.5 to 5.0 produced the best results. Optimal soil conductivity appeared to lie between 10 and 45 microsiemens
.
An illuminance
of 6400–8600 lx
(600–800 fc
) proved to be optimal when plants were grown under sunlight, high pressure sodium
, and metal halide lamp
s. However, specimens placed under an even combination of Gro-Lux and cool white fluorescent lamp
s at 5400–7500 lx (500–700 fc) exhibited the most vibrant colours (although growth rates remained the same). Plants moved from the former to the latter light set up showed a significant change in pigmentation; green leaf blades turned bronzy and speckles on the pitchers darkened markedly.
Nepenthes fusca was found to respond well to a quarter-strength fertilizer
that was applied to the pitchers. Ant
s were also an effective food source.
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 Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
. It is found throughout a wide altitudinal range
Altitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
and is almost always epiphytic in nature, primarily growing in mossy forest.
The specific epithet fusca is derived from the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
word fuscus, meaning "dark brown" or "dusky", and refers to the colour of the pitchers.
Botanical history
The first known collection of N. fusca was made by Frederik EndertFrederik Endert
Frederik Hendrik Endert was a Dutch botanist and plant collector.In 1915, Endert was appointed a Forest Officer in the Dutch East Indies Forest Service. From 1918 onwards he worked closely with the Forest Research Institute at Buitenzorg , Java...
on October 12, 1925, from Mount Kemul
Mount Kemul
Mount Kemul is a mountain in East Kalimantan. It is the type locality of the pitcher plant species Nepenthes fusca and Nepenthes mollis....
in East Kalimantan
East Kalimantan
East Kalimantan is the second largest Indonesian province, located on the Kalimantan region on the east of Borneo island. The resource-rich province has two major cities, Samarinda and Balikpapan...
, at an elevation of 1500 m. It was discovered during an expedition to central Borneo by the Forest Research Institute of Bogor
Bogor
Bogor is a city on the island of Java in the West Java province of Indonesia. The city is located in the center of the Bogor Regency , 60 kilometers south of the Indonesian capital Jakarta...
(then known as Buitenzorg), on which Endert also made the only known collection of N. mollis
Nepenthes mollis
Nepenthes mollis , or the Velvet Pitcher-Plant, is a tropical pitcher plant species native to Kalimantan, Borneo. It is known only from a single dried herbarium specimen and is the sole recognised species in the genus Nepenthes of which the pitchers are unknown.The habitat of N. mollis is listed as...
. The N. fusca specimen, designated as Endert 3955, includes male floral material and is deposited at Herbarium Bogoriense (BO), the 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...
of the Bogor Botanical Gardens
Bogor Botanical Gardens
The Bogor Botanical Gardens are located 60 km south of the capital of Jakarta in Bogor, Indonesia. The botanical gardens are situated in the city center of Bogor and adjoin the Istana Bogor...
. Endert wrote about this pitcher plant in a detailed 1927 account of the expedition, although he misidentified it as N. veitchii
Nepenthes veitchii
Nepenthes veitchii |James Veitch]], nurseryman of the Veitch Nurseries), or Veitch's Pitcher-Plant, is a Nepenthes species from the island of Borneo. The plant is widespread in north-western Borneo and can also be found in parts of Kalimantan. N...
.
Nepenthes fusca was 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...
in 1928 by Dutch
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
botanist B. H. Danser
B. H. Danser
Benedictus Hubertus Danser , often abbreviated B. H. Danser, was a Dutch taxonomist and botanist...
in his seminal monograph "The Nepenthaceae of the Netherlands Indies
The Nepenthaceae of the Netherlands Indies
"The Nepenthaceae of the Netherlands Indies" is a seminal monograph by B. H. Danser on the tropical pitcher plants of the Dutch East Indies, North Borneo, the Malay Peninsula, and eastern New Guinea...
". Danser based his description solely on Endert 3955, citing no other specimens. He wrote of N. fusca:
This new species is, together with N. VeitchiiNepenthes veitchiiNepenthes veitchii |James Veitch]], nurseryman of the Veitch Nurseries), or Veitch's Pitcher-Plant, is a Nepenthes species from the island of Borneo. The plant is widespread in north-western Borneo and can also be found in parts of Kalimantan. N...
and N. stenophyllaNepenthes stenophyllaNepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
, very nearly related to N. maximaNepenthes maximaNepenthes maxima , the Great Pitcher-Plant, is a carnivorous pitcher plant species of the genus Nepenthes. It has a relatively wide distribution covering Sulawesi, New Guinea, and the Maluku Islands. It is closely related to N. eymae....
, but can not be confounded with any of these species. According to Endert it grew in the forest on a narrow, stony mountain ridge covered with humus, and was not rare.
Nepenthes of Mount Kinabalu
Nepenthes of Mount Kinabalu is a monograph by Shigeo Kurata on the tropical pitcher plants of Mount Kinabalu and the surrounding area of Kinabalu National Park in Sabah, Borneo. It was published in 1976 by Sabah National Parks Trustees as the second booklet of the Sabah National Parks series...
as representing N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
(as distinct from N. fallax). Matthew Jebb
Matthew Jebb
Dr. Matthew H. P. Jebb is an Irish taxonomist and botanist specialising in the ant plant genera Squamellaria, Myrmecodia, Hydnophytum, Myrmephytum and Anthorrhiza, as well as the carnivorous plant genus Nepenthes....
does not consider these differences significant enough to merit distinction at the species level. He suggests that the type specimen consists of intermediate lower and upper pitchers as opposed to true forms of either, making them appear atypical.
Much of this taxonomic uncertainty stems from the fact that N. fusca has not been recollected from the type locality and many similar plants have been lumped under this taxon. Matthew Jebb
Matthew Jebb
Dr. Matthew H. P. Jebb is an Irish taxonomist and botanist specialising in the ant plant genera Squamellaria, Myrmecodia, Hydnophytum, Myrmephytum and Anthorrhiza, as well as the carnivorous plant genus Nepenthes....
and 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,...
attempted to resolve this confusion in their 1997 monograph by interpreting N. fusca as a widespread and variable species.
Subspecies
Two subspeciesSubspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of N. fusca have been described:
- Nepenthes fusca subsp. apoensis J.H.AdamJ. H. AdamJumaat Haji Adam is a botanist and taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Adam has described numerous Nepenthes taxa, mostly with C. C. Wilcock, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana, N. ×...
& WilcockC. C. WilcockChristopher C. Wilcock is a taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Together with J. H. Adam, Wilcock has described several Nepenthes taxa, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana and N. ×...
ex JebbMatthew JebbDr. Matthew H. P. Jebb is an Irish taxonomist and botanist specialising in the ant plant genera Squamellaria, Myrmecodia, Hydnophytum, Myrmephytum and Anthorrhiza, as well as the carnivorous plant genus Nepenthes....
& CheekMartin CheekDr. 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,...
(1997) nom.nud.Nomen nudumThe phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...
[=N. stenophyllaNepenthes stenophyllaNepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
] - Nepenthes fusca subsp. kostermansiana J.H.AdamJ. H. AdamJumaat Haji Adam is a botanist and taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Adam has described numerous Nepenthes taxa, mostly with C. C. Wilcock, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana, N. ×...
& WilcockC. C. WilcockChristopher C. Wilcock is a taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Together with J. H. Adam, Wilcock has described several Nepenthes taxa, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana and N. ×...
ex JebbMatthew JebbDr. Matthew H. P. Jebb is an Irish taxonomist and botanist specialising in the ant plant genera Squamellaria, Myrmecodia, Hydnophytum, Myrmephytum and Anthorrhiza, as well as the carnivorous plant genus Nepenthes....
& CheekMartin CheekDr. 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,...
(1997) nom.nud.Nomen nudumThe phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...
Both were originally coined by J. H. Adam
J. H. Adam
Jumaat Haji Adam is a botanist and taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Adam has described numerous Nepenthes taxa, mostly with C. C. Wilcock, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana, N. ×...
and C. C. Wilcock
C. C. Wilcock
Christopher C. Wilcock is a taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Together with J. H. Adam, Wilcock has described several Nepenthes taxa, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana and N. ×...
and subsequently published in Jebb and Cheek's 1997 monograph, "A skeletal revision of Nepenthes (Nepenthaceae)
A skeletal revision of Nepenthes (Nepenthaceae)
"A skeletal revision of Nepenthes " is a monograph by Matthew Jebb and Martin Cheek on the tropical pitcher plants of the genus Nepenthes. It was published in the May 1997 issue of the botanical journal Blumea. The work represented the first revision of the entire genus since John Muirhead...
". As these names were published without an adequate description, they are both considered nomina nuda
Nomen nudum
The phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...
. The former is based on Chai 35939, a specimen collected from Mount Apo. Schlauer considers it synonymous with N. fallax, a taxon that is in turn considered conspecific with N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
by most authors.
Nepenthes fusca subsp. kostermansiana is thought to be assigned to the correct species. The type specimen (Kostermans 21495) was collected on October 25, 1963, from Kelai River
Kelai River
Kelai River is a river of Borneo, Indonesia. It is a tributary of the Berau River....
, Mount Njapa, Berau. It is deposited at the National Herbarium of the Netherlands
National Herbarium of the Netherlands
The National Herbarium of the Netherlands was established in 1999 through a decentralized merger of the major university herbaria of Leiden , Utrecht and Wageningen...
in Leiden.
Nepenthes maxima
Nepenthes maxima
Nepenthes maxima , the Great Pitcher-Plant, is a carnivorous pitcher plant species of the genus Nepenthes. It has a relatively wide distribution covering Sulawesi, New Guinea, and the Maluku Islands. It is closely related to N. eymae....
, a species native to Sulawesi
Sulawesi
Sulawesi is one of the four larger Sunda Islands of Indonesia and is situated between Borneo and the Maluku Islands. In Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger Indonesian populations.- Etymology :The Portuguese were the first to...
, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, and the Maluku Islands
Maluku Islands
The Maluku Islands are an archipelago that is part of Indonesia, and part of the larger Maritime Southeast Asia region. Tectonically they are located on the Halmahera Plate within the Molucca Sea Collision Zone...
, was once thought to extend to Borneo as well. Some authors even wrote that it was widespread on the island. This confusion stemmed from the likeness of N. fusca and N. maxima, and from apparently mislabelled seeds collected by Charles Curtis
Charles Curtis (botanist)
Charles Curtis was an English botanist who was sent by James Veitch & Sons to search for new plant species in Madagascar, Borneo, Sumatra, Java and the Moluccas, before settling in Penang, where he became the first superintendent of the Penang Botanic Gardens.-Early days:Curtis was born in...
. Curtis was not meticulous in recording where he located individual plants; although it was originally believed that he collected N. curtisii (now considered synonymous with N. maxima) in Borneo, botanist Charles Clarke
Charles Clarke (botanist)
Dr. Charles M. Clarke is a botanist and taxonomist specialising in the carnivorous plant genus Nepenthes. Clarke has an honours degree in Botany from Monash University in Melbourne, and a Ph.D. in Ecosystem Management at the University of New England, in Armidale, New South Wales.Clarke first...
points out that he also visited Sulawesi
Sulawesi
Sulawesi is one of the four larger Sunda Islands of Indonesia and is situated between Borneo and the Maluku Islands. In Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger Indonesian populations.- Etymology :The Portuguese were the first to...
on the same trip, and N. maxima is common there.
Matthew Jebb
Matthew Jebb
Dr. Matthew H. P. Jebb is an Irish taxonomist and botanist specialising in the ant plant genera Squamellaria, Myrmecodia, Hydnophytum, Myrmephytum and Anthorrhiza, as well as the carnivorous plant genus Nepenthes....
and 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,...
resolved this confusion in their 1997 monograph by referring a number of Bornean plants identified as N. maxima to N. fusca, thereby excluding the former from the island.
Nepenthes zakriana
In 1996, J. H. AdamJ. H. Adam
Jumaat Haji Adam is a botanist and taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Adam has described numerous Nepenthes taxa, mostly with C. C. Wilcock, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana, N. ×...
and C. C. Wilcock
C. C. Wilcock
Christopher C. Wilcock is a taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Together with J. H. Adam, Wilcock has described several Nepenthes taxa, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana and N. ×...
described Nepenthes curtisii subsp. zakriana. Ten years later, Adam and Hafiza A. Hamid elevated it to species status as Nepenthes zakriana (n, not /ˌzækriˈænə/). The authors described the taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
as a Sabah
Sabah
Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...
endemic growing at elevations of 1200 to 1500 m.
Adam and Hafiza wrote that N. zakriana "consistently differed from Nepenthes fusca by prominent raised midribs, extended beyond apex forming an apical glandular appendages on lower lid surface of both upper and lower pitchers; and basal half portion of the midrib developed in nail-shaped glandular crest". However, a number of authors soon voiced their doubts as to whether N. zakriana merited species status and in Pitcher Plants of Borneo by Anthea Phillipps
Anthea Phillipps
Anthea Phillipps B.Sc. is a British botanist. Phillipps was brought up in Sabah, Borneo as a child . She received a Botany degree from the University of Durham, England. She worked at the Sabah Museum before joining the Sabah Parks service from 1980 to 1987 as Park Ecologist, where she studied...
, Anthony Lamb
Anthony Lamb
Anthony L. Lamb M.A., Dip. Ag., D.T.A. is a British botanist, born in Sri Lanka, and specialising in the flora of Borneo. Lamb was educated at Blundell's School in Tiverton and at St John's College at Cambridge...
, and Ch'ien Lee
Ch'ien Lee
Ch'ien C. Lee is a photographer and botanist specialising in the carnivorous plant genus Nepenthes. Lee has described several new Nepenthes species, including N. chaniana, N. gantungensis, N. glandulifera, N. jamban, N. lingulata, N. palawanensis, N. pitopangii,...
, these features were considered to fall within the natural variability of N. fusca.
Nepenthes sp. A
In his 1997 monograph, Nepenthes of BorneoNepenthes of Borneo
Nepenthes of Borneo is a monograph by Charles Clarke on the tropical pitcher plants of Borneo. It was first published in 1997 by Natural History Publications , and reprinted in 2006. Clarke describes it as "primarily an ecological monograph"...
, Charles Clarke
Charles Clarke (botanist)
Dr. Charles M. Clarke is a botanist and taxonomist specialising in the carnivorous plant genus Nepenthes. Clarke has an honours degree in Botany from Monash University in Melbourne, and a Ph.D. in Ecosystem Management at the University of New England, in Armidale, New South Wales.Clarke first...
lists the undescribed taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
"Nepenthes sp. A", which has been recorded from Gunung Mulu National Park
Gunung Mulu National Park
Gunung Mulu National Park near Miri, Sarawak, Malaysian Borneo, is a UNESCO World Heritage Site that encompasses incredible caves and karst formations in a mountainous equatorial rainforest setting...
in Sarawak
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
. It bears a close resemblance to N. fusca and may be conspecific with it, although its colouration is unusual for the species. The pitchers of this plant match J. H. Adam
J. H. Adam
Jumaat Haji Adam is a botanist and taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Adam has described numerous Nepenthes taxa, mostly with C. C. Wilcock, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana, N. ×...
and C. C. Wilcock
C. C. Wilcock
Christopher C. Wilcock is a taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Together with J. H. Adam, Wilcock has described several Nepenthes taxa, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana and N. ×...
's description of N. faizaliana
Nepenthes faizaliana
Nepenthes faizaliana is a tropical pitcher plant endemic to the limestone cliffs of Gunung Mulu National Park in Sarawak, Borneo. It is thought to be most closely related to N. boschiana.-Botanical history:...
, but the latter is now known to have a round lid (as opposed to narrowly triangular in N. fusca and "Nepenthes sp. A"), suggesting that these two taxa are not closely related. Clarke proposes that this taxon might fall under Jebb and Cheek's more inclusive concept of N. fusca, but retains it as an undescribed species because it remains poorly known.
"Nepenthes sp. A" was first illustrated in a 1988 article by Anthea Phillipps
Anthea Phillipps
Anthea Phillipps B.Sc. is a British botanist. Phillipps was brought up in Sabah, Borneo as a child . She received a Botany degree from the University of Durham, England. She worked at the Sabah Museum before joining the Sabah Parks service from 1980 to 1987 as Park Ecologist, where she studied...
and Anthony Lamb
Anthony Lamb
Anthony L. Lamb M.A., Dip. Ag., D.T.A. is a British botanist, born in Sri Lanka, and specialising in the flora of Borneo. Lamb was educated at Blundell's School in Tiverton and at St John's College at Cambridge...
, where it was considered an undescribed species.
Description
The leaves of this species are petiolate and coriaceous in texture. The lamina or leaf blade is obovate-oblong in shape and measures up to 15 cm in length by 6 cm in width. Its apex is acute to obtuse and may even be slightly peltate. The base of the lamina is gradually attenuate towards the petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
. The petiole (≤4 cm long) is grooved lengthwise and bears a pair of narrow wings that form a semi-amplexicaul sheath around the stem. Up to 3 longitudinal veins are present on either side of the midrib, although they are indistinct. Pinnate veins are numerous. 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 measure up to 5 cm in length.
Rosette and lower pitchers are cylindrical throughout. They usually grow to 20 cm in height by 4 cm in width, although exceptional specimens up to 28 cm have been recorded. A pair of fringed wings (≤5 mm wide) runs down the ventral surface of the pitcher and bears fringe elements measuring up to 10 mm and spaced 6 mm apart. The 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 :...
ular region is restricted to the lower portion of the pitcher's inner surface. The glands are small, overarched, and occur at a density of 600 to 650 per square centimetre. The pitcher mouth is positioned horizontally at the front, becoming elongated into a neck at the rear. The 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...
is flattened and expanded (≤12 mm wide), but bears only indistinct teeth (≤0.3 mm long). 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 very narrowly ovate in shape and has a distinctive basal crest on its lower surface. An unbranched spur measuring up to 10 mm in length is inserted near the base of the lid.
Upper pitchers differ markedly in shape, being narrowly infundibular in the lower two-thirds and becoming widely infundibular above. They are similar in size to their lower counterparts, typically measuring up to 18 cm, with some larger forms reaching 26 cm. The tiny digestive glands are overarched and number 1500 to 2000 per square centimetre. The pitcher lid is very narrowly triangular with the margins and apex curved downwards. In aerial pitchers, the wings are reduced to ribs.
Nepenthes fusca produces a compact 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...
. The peduncle
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...
is up to 6 cm long, while 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...
is not known to exceed 10 cm. Partial peduncles are one- or two-flowered, up to 8 mm long, and lack a bract
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
. Sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s are elliptic and up to 4 mm long. A study of 120 pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
samples taken from the type specimen (Endert 3955) found the mean pollen diameter to be 34.8 μm
Micrometre
A micrometer , is by definition 1×10-6 of a meter .In plain English, it means one-millionth of a meter . Its unit symbol in the International System of Units is μm...
(SE
Standard error (statistics)
The standard error is the standard deviation of the sampling distribution of a statistic. The term may also be used to refer to an estimate of that standard deviation, derived from a particular sample used to compute the estimate....
= 0.6; CV
Coefficient of variation
In probability theory and statistics, the coefficient of variation is a normalized measure of dispersion of a probability distribution. It is also known as unitized risk or the variation coefficient. The absolute value of the CV is sometimes known as relative standard deviation , which is...
= 9.1%).
Developing parts of the plant 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 long, brown hairs. However, most of these disappear during the normal course of development, and mature parts only have a sparse covering of short, brown hairs.
Ecology
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
, where its range stretches from Central Kalimantan
Central Kalimantan
Central Kalimantan is a province of Indonesia, one of four in Kalimantan - the Indonesian part of the island of Borneo. Its provincial capital is Palangka Raya.The province has a population of just over 2.2 million at the 2010 Census...
to northwestern Sabah
Sabah
Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...
. It has been recorded from Brunei
Brunei
Brunei , officially the State of Brunei Darussalam or the Nation of Brunei, the Abode of Peace , is a sovereign state located on the north coast of the island of Borneo, in Southeast Asia...
, Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
(Kalimantan
Kalimantan
In English, the term Kalimantan refers to the Indonesian portion of the island of Borneo, while in Indonesian, the term "Kalimantan" refers to the whole island of Borneo....
), and Malaysia (Sabah
Sabah
Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...
and Sarawak
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
). The species has a wide altitudinal distribution and is typically found at elevations of 1200 to 2500 m above sea level. However, N. fusca has occasionally been reported from lowland hills down to 600 m and in Sarawak it has been found at only 300 m in hill forest.
Nepenthes fusca is most commonly found as an epiphyte
Epiphyte
An epiphyte is a plant that grows upon another plant non-parasitically or sometimes upon some other object , derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone and in the...
in shady mossy forest on ridge tops, where it may grow 10 to 15 m off the ground. This makes it particularly difficult to find and often the only evidence of its presence are dead pitchers that have fallen to the forest floor. In this respect, it can be considered the "ecological equivalent" of N. bongso
Nepenthes bongso
Nepenthes bongso is a tropical pitcher plant endemic to Sumatra, where it has an altitudinal distribution of 1000–2700 m above sea level. The specific epithet bongso refers to the Indonesian legend of Putri Bungsu , the spirit guardian of Mount Marapi.The species was formally described by Pieter...
from Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
. More rarely, N. fusca grows terrestrially in exposed sites near montane forest or along logging roads. It is often sympatric with species such as N. reinwardtiana
Nepenthes reinwardtiana
Nepenthes reinwardtiana , Reinwardt's Pitcher-Plant, is a Nepenthes species found on the islands of Borneo and Sumatra. Although some sources have included Peninsular Malaysia and Singapore within the range of this species, these records appear to be erroneous.Nepenthes reinwardtiana has an...
, N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
, and N. tentaculata
Nepenthes tentaculata
Nepenthes tentaculata , or the Fringed Pitcher-Plant, is a tropical pitcher plant with a very wide distribution across Borneo and Sulawesi...
, and natural hybrids with all of these have been recorded.
Mount Kinabalu
Mount Kinabalu is a prominent mountain on the island of Borneo in Southeast Asia. It is located in the East Malaysian state of Sabah and is protected as Kinabalu National Park, a World Heritage Site. Kinabalu is the tallest peak in Borneo's Crocker Range and is the tallest mountain in the Malay...
, including Kambarangoh
Kambarangoh
Kambarangoh is an area along the summit trail to Low's Peak on Mount Kinabalu in Sabah, Borneo. It lies between the Power Station and Layang-Layang. It is named after the only telecommunications station on the mountain, which is owned by Kambarangoh Telecoms.The road leading up to the Power...
, the Marai Parai
Marai Parai
Marai Parai or Marei Parei is a plateau on the northwestern side of Mount Kinabalu, in Malaysia. The mountain can be climbed from this side, although few parties attempt this route...
plateau
Plateau
In geology and earth science, a plateau , also called a high plain or tableland, is an area of highland, usually consisting of relatively flat terrain. A highly eroded plateau is called a dissected plateau...
, the mountain's East Ridge, and the Bambangan River at around 1500 m. It also grows on the side of the road connecting the park headquarters and the power station, despite being frequently cut back as part of road maintenance. This is one of the few places where N. fusca may be easily seen by visitors. These roadside plants were greatly affected by the El Niño climatic phenomenon of 1997 to 1998. The resulting dry period severely depleted the population, such that "almost all the plants were destroyed". Nearby plants from more sheltered locations fared better and appeared to have recovered by the following year. A number of N. fusca plants have also been transplanted to the Mesilau nature trail
Mesilau
Mesilau, named after Mesilau River, is an area situated at approximately 2000 m above sea level on the East Ridge of Mount Kinabalu in Kinabalu National Park, Sabah, Malaysian Borneo. It is the site of the Mesilau Nature Resort, which is owned and operated by Sutera Sanctuary Lodges...
.
Nepenthes fusca can be viewed along the road leading to the disused Mamut copper mine, where it is sympatric with N. macrovulgaris
Nepenthes macrovulgaris
Nepenthes macrovulgaris , or the Serpentine Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. It is a lowland plant that typically grows at altitudes ranging from 300 to 1200 m in sub-montane forest clearings and mossy forest...
, N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
, and the natural hybrid N. fusca × N. stenophylla; N. burbidgeae
Nepenthes burbidgeae
Nepenthes burbidgeae , also known as the painted pitcher plant or Burbidge's Pitcher-Plant, is a tropical pitcher plant with a patchy distribution around Mount Kinabalu and neighbouring Mount Tambuyukon in Sabah, Borneo.-Botanical history:...
grows a short distance away.
The species also occurs on nearby Mount Tambuyukon
Mount Tambuyukon
Mount Tambuyukon or Tamboyukon is Malaysia's third highest mountain at 2,579 m . It lies close to the famous Mount Kinabalu. The mountain supports a wide range of unique flora and fauna, including a number of pitcher plant species of the genus Nepenthes....
. On Mount Trus Madi
Mount Trus Madi
Mount Trus Madi or Trusmadi is Malaysia's second highest mountain at . It lies in the state of Sabah, close to Mount Kinabalu. The mountain supports a wide range of unique flora and fauna, perhaps most notably Nepenthes macrophylla, a species of pitcher plant.The natural hybrid Nepenthes ×...
, N. fusca has been found at an elevation of almost 1800 m, growing as an epiphyte in Eleocarpus trees. An atypical yellow form grows on Mount Lumarku
Mount Lumarku
Mount Lumarku or Lumaku is a mountain in southwestern Sabah. The pitcher plant species Nepenthes fusca, Nepenthes hurrelliana, and Nepenthes tentaculata are native to this mountain....
in Sabah. On Mount Mulu
Mount Mulu
Mount Mulu is a sandstone and shale mountain. At 2376 m, it is the second highest mountain in the state of Sarawak, after Mount Murud. It is located within the boundaries of Gunung Mulu National Park, which is named after it....
in Sarawak, N. fusca grows below 1200 m, such that its distribution does not overlap with that of two other epiphytes: N. vogelii
Nepenthes vogelii
Nepenthes vogelii is a tropical pitcher plant endemic to Borneo. It is thought to be most closely related to N. fusca.-Botanical history:...
, which grows from 1200 to 1500 m, and N. hurrelliana
Nepenthes hurrelliana
Nepenthes hurrelliana is a tropical pitcher plant endemic to Borneo, where it has been recorded from northern Sarawak, southwestern Sabah, and Brunei. It is of putative hybrid origin; its two original parent species are thought to be N. fusca and N. veitchii...
, which occurs above 1500 m. Other notable locations include Mount Alab (the highest peak of the Crocker Range
Crocker Range
Crocker Range , is a mountain range on the island of Borneo. Politically, it is within the boundary of the Malaysian state of Sabah, located in the northern half of Borneo. The mountain range separates the east coast and west coast of Sabah. At an average height of 1800m, it is the highest mountain...
), the Kimanis
Kimanis
Kimanis is a fully integrated township and also a parliamentary constituency in the West Coast Division of Sabah, Malaysia. It is located approximately 45 kilometres south of the city of Kota Kinabalu. Kimanis used to be the base for the American company which obtained a lease over North Borneo...
–Keningau
Keningau
Keningau is a sprawling timber and agricultural town and district located in the Interior Division of Sabah, east Malaysia on the island of Borneo...
Road that runs through the Crocker Range, Mount Njapa (where it grows at 1000 m), and the summit area of Mount Apo Dari (1500 m).
In the Hose Mountains
Hose Mountains
The Hose Mountains are a mountain range in central Sarawak, Borneo. They span the area between the watersheds of the Balleh and Balui Rivers. The mountains are covered in virgin tropical rainforest that supports a rich ecosystem of fauna and flora, including many endemic species...
of central Sarawak, N. fusca is typically found growing as an epiphyte in lower montane forest at 700–1200 m. It is also an uncommon inhabitant of roadside embankments there.
Nepenthes fusca is classified as Vulnerable
Vulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
on the 2006 IUCN Red List of Threatened Species
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
, based on an assessment carried out in 2000. This agrees with an informal assessment made by Charles Clarke
Charles Clarke (botanist)
Dr. Charles M. Clarke is a botanist and taxonomist specialising in the carnivorous plant genus Nepenthes. Clarke has an honours degree in Botany from Monash University in Melbourne, and a Ph.D. in Ecosystem Management at the University of New England, in Armidale, New South Wales.Clarke first...
in 1997, who also classified the species as Vulnerable based on the IUCN
World Conservation Union
The International Union for Conservation of Nature and Natural Resources is an international organization dedicated to finding "pragmatic solutions to our most pressing environment and development challenges." The organization publishes the IUCN Red List, compiling information from a network of...
criteria. However, Clarke noted that since substantial populations of N. fusca lie within the boundaries of national park
National park
A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individual nations designate their own national parks differently A national park is a reserve of natural, semi-natural, or developed land that a sovereign state declares or...
s, they "are unlikely to become threatened in the foreseeable future". Taking this into account, he suggested a revised assessment of Conservation Dependent
Conservation Dependent
Conservation Dependent was an IUCN category assigned to species or lower taxa which were dependent on conservation efforts to prevent the taxon becoming threatened with extinction...
. However, it differs from the assessment by the World Conservation Monitoring Centre
World Conservation Monitoring Centre
The United Nations Environment Programme's World Conservation Monitoring Centre is an executive agency of the United Nations Environment Programme, based in Cambridge in the United Kingdom. UNEP-WCMC has been part of UNEP since 2000, and has responsibility for biodiversity assessment and support...
, which classified N. fusca as "not threatened", its lowest conservation status.
Related species
Nepenthes fusca is thought to be most closely related to N. hurrellianaNepenthes hurrelliana
Nepenthes hurrelliana is a tropical pitcher plant endemic to Borneo, where it has been recorded from northern Sarawak, southwestern Sabah, and Brunei. It is of putative hybrid origin; its two original parent species are thought to be N. fusca and N. veitchii...
, N. platychila
Nepenthes platychila
Nepenthes platychila is a species of pitcher plant endemic to the Hose Mountains of central Sarawak. It is notable for its smooth peristome and funnel-shaped upper pitchers....
, N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
, and N. vogelii
Nepenthes vogelii
Nepenthes vogelii is a tropical pitcher plant endemic to Borneo. It is thought to be most closely related to N. fusca.-Botanical history:...
. The enigmatic N. mollis
Nepenthes mollis
Nepenthes mollis , or the Velvet Pitcher-Plant, is a tropical pitcher plant species native to Kalimantan, Borneo. It is known only from a single dried herbarium specimen and is the sole recognised species in the genus Nepenthes of which the pitchers are unknown.The habitat of N. mollis is listed as...
, which some authors have suggested is conspecific with N. hurrelliana, may also be closely allied.
The lower pitchers of N. hurrelliana are distinctive, but the upper ones bear a close resemblance to those of N. fusca. Of the Bornean pitcher plant
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...
flora, only these two species have such a narrowly triangular lid. The upper pitchers of N. hurrelliana differ in having a horizontal mouth that rises abruptly into a long neck at the back and in having a hirsute basal crest on the underside of the lid.
Nepenthes hurrelliana is particularly similar to a form of N. fusca from the southern portion of the Crocker Range
Crocker Range
Crocker Range , is a mountain range on the island of Borneo. Politically, it is within the boundary of the Malaysian state of Sabah, located in the northern half of Borneo. The mountain range separates the east coast and west coast of Sabah. At an average height of 1800m, it is the highest mountain...
in Sabah
Sabah
Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...
. This form exhibits a wider peristome, longer neck, and a more triangular lid than most other examples of the species. However, the peristome is still not as well developed as in N. hurrelliana and the plant lacks the dense indumentum of the latter. Furthermore, N. hurrelliana differs in the distribution of nectar glands on the lower surface of its lid.
The first known collection of N. vogelii
Nepenthes vogelii
Nepenthes vogelii is a tropical pitcher plant endemic to Borneo. It is thought to be most closely related to N. fusca.-Botanical history:...
, made in 1961, was labelled as N. fusca. In 1969, botanist Shigeo Kurata
Shigeo Kurata
is a Japanese botanist and Nepenthes taxonomist whose work in the 1960s and 1970s contributed much to the current popularity of these plants. Of particular note is his 1976 guide, Nepenthes of Mount Kinabalu....
examined this specimen and noted that it did not fall within the known variation exhibited by N. fusca. Nevertheless, the species remained undescribed until 2002. Nepenthes vogelii differs in having much smaller pitchers and lacking appendages on the underside of the lid. In addition, the lid of N. vogelii is broadly triangular as opposed to the narrowly triangular lid of N. fusca. The colour of the pitchers—light cream with dark speckles—is also distinctive.
Nepenthes faizaliana
Nepenthes faizaliana
Nepenthes faizaliana is a tropical pitcher plant endemic to the limestone cliffs of Gunung Mulu National Park in Sarawak, Borneo. It is thought to be most closely related to N. boschiana.-Botanical history:...
also bears a resemblance to N. fusca. In their description of the former, J. H. Adam
J. H. Adam
Jumaat Haji Adam is a botanist and taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Adam has described numerous Nepenthes taxa, mostly with C. C. Wilcock, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana, N. ×...
and C. C. Wilcock
C. C. Wilcock
Christopher C. Wilcock is a taxonomist specialising in the carnivorous pitcher plant genus Nepenthes.Together with J. H. Adam, Wilcock has described several Nepenthes taxa, including the species N. faizaliana and N. mapuluensis, as well as the natural hybrids N. × alisaputrana and N. ×...
distinguished these taxa
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
on the basis of inflorescence structure, the size of the glandular region on the inner surface of upper pitchers, and the development and characteristics of the 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...
. In addition, N. fusca differs in having a very narrow pitcher lid, as opposed to the orbicular lid of N. faizaliana.
Nepenthes platychila can be distinguished from N. fusca on the basis of its much wider peristome and lid, the latter lacking appendages on its lower surface. Nepenthes fusca is also thought to be closely related to Sulawesi
Sulawesi
Sulawesi is one of the four larger Sunda Islands of Indonesia and is situated between Borneo and the Maluku Islands. In Indonesia, only Sumatra, Borneo, and Papua are larger in territory, and only Java and Sumatra have larger Indonesian populations.- Etymology :The Portuguese were the first to...
's N. eymae
Nepenthes eymae
Nepenthes eymae is a tropical pitcher plant endemic to Sulawesi, where it grows at elevations of 1000–2000 m above sea level. It is very closely related to N. maxima, from which it differs in its wine glass-shaped upper pitchers....
, and N. maxima
Nepenthes maxima
Nepenthes maxima , the Great Pitcher-Plant, is a carnivorous pitcher plant species of the genus Nepenthes. It has a relatively wide distribution covering Sulawesi, New Guinea, and the Maluku Islands. It is closely related to N. eymae....
, which is widespread in Sulawesi, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
, and the Maluku Islands
Maluku Islands
The Maluku Islands are an archipelago that is part of Indonesia, and part of the larger Maritime Southeast Asia region. Tectonically they are located on the Halmahera Plate within the Molucca Sea Collision Zone...
.
Natural hybrids
Due its widespread distribution throughout Borneo, N. fusca forms natural hybrids with a relatively large number of other species. However, like N. fusca itself, these are often hard to find due to the species's epiphyticEpiphyte
An epiphyte is a plant that grows upon another plant non-parasitically or sometimes upon some other object , derives its moisture and nutrients from the air and rain and sometimes from debris accumulating around it, and is found in the temperate zone and in the...
growth habit.
N. burbidgeae × N. fusca
Nepenthes burbidgeaeNepenthes burbidgeae
Nepenthes burbidgeae , also known as the painted pitcher plant or Burbidge's Pitcher-Plant, is a tropical pitcher plant with a patchy distribution around Mount Kinabalu and neighbouring Mount Tambuyukon in Sabah, Borneo.-Botanical history:...
× N. fusca has been known since at least the early 1980s, when it was found during an expedition to Sabah.
N. fusca × N. lowii
This hybrid was initially identified as a cross with N. chanianaNepenthes chaniana
Nepenthes chaniana ]]) is a highland pitcher plant species belonging to the genus Nepenthes. It is characterised by a dense indumentum of long, white hairs. Pitchers are cylindrical and mostly white to yellow in colouration....
(known as N. pilosa
Nepenthes pilosa
Nepenthes pilosa is a tropical pitcher plant endemic to Borneo. It is characterised by a dense indumentum of long yellow-brown hairs. Pitchers have a distinctive hook-shaped appendage on the underside of the lid...
at the time) by Charles Clarke
Charles Clarke (botanist)
Dr. Charles M. Clarke is a botanist and taxonomist specialising in the carnivorous plant genus Nepenthes. Clarke has an honours degree in Botany from Monash University in Melbourne, and a Ph.D. in Ecosystem Management at the University of New England, in Armidale, New South Wales.Clarke first...
. However, Anthea Phillipps
Anthea Phillipps
Anthea Phillipps B.Sc. is a British botanist. Phillipps was brought up in Sabah, Borneo as a child . She received a Botany degree from the University of Durham, England. She worked at the Sabah Museum before joining the Sabah Parks service from 1980 to 1987 as Park Ecologist, where she studied...
, Anthony Lamb
Anthony Lamb
Anthony L. Lamb M.A., Dip. Ag., D.T.A. is a British botanist, born in Sri Lanka, and specialising in the flora of Borneo. Lamb was educated at Blundell's School in Tiverton and at St John's College at Cambridge...
, and Ch'ien Lee
Ch'ien Lee
Ch'ien C. Lee is a photographer and botanist specialising in the carnivorous plant genus Nepenthes. Lee has described several new Nepenthes species, including N. chaniana, N. gantungensis, N. glandulifera, N. jamban, N. lingulata, N. palawanensis, N. pitopangii,...
differ in their interpretation, noting that the plant exhibits influences of N. fusca, such as a triangular lid and an elongated neck. They write that both N. fusca and N. lowii
Nepenthes lowii
Nepenthes lowii , or Low's Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. It is named after Hugh Low, who discovered it on Mount Kinabalu...
are common in the summit area, whereas N. chaniana is rare. Another possible parent species, N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
, is apparently absent from the site.
Nepenthes fusca × N. lowii was discovered by Rob Cantley
Rob Cantley
Robert Cantley is a conservationist and Managing Director of Borneo Exotics, a Sri Lankan-based plant nursery specialising in tissue-cultured and seed-grown Nepenthes species and hybrids. Cantley has contributed to a number of papers on Nepenthes...
and Charles Clarke
Charles Clarke (botanist)
Dr. Charles M. Clarke is a botanist and taxonomist specialising in the carnivorous plant genus Nepenthes. Clarke has an honours degree in Botany from Monash University in Melbourne, and a Ph.D. in Ecosystem Management at the University of New England, in Armidale, New South Wales.Clarke first...
on Bukit Batu Lawi
Bukit Batu Lawi
Bukit Batu Lawi is a mountain located in the Malaysian part of Borneo. At 2,046 m , it is one of the highest mountains in the state of Sarawak.- Further reading :* Lightner, Sam Jr. All Elevations Unknown...
in Sarawak
Sarawak
Sarawak is one of two Malaysian states on the island of Borneo. Known as Bumi Kenyalang , Sarawak is situated on the north-west of the island. It is the largest state in Malaysia followed by Sabah, the second largest state located to the North- East.The administrative capital is Kuching, which...
. Clarke later found larger plants of this hybrid in the Crocker Range
Crocker Range
Crocker Range , is a mountain range on the island of Borneo. Politically, it is within the boundary of the Malaysian state of Sabah, located in the northern half of Borneo. The mountain range separates the east coast and west coast of Sabah. At an average height of 1800m, it is the highest mountain...
of Sabah
Sabah
Sabah is one of 13 member states of Malaysia. It is located on the northern portion of the island of Borneo. It is the second largest state in the country after Sarawak, which it borders on its southwest. It also shares a border with the province of East Kalimantan of Indonesia in the south...
, particularly near the summit of Mount Alab. The pitchers of N. fusca × N. lowii have a slight constriction in the middle and range in colour from green to dark purple throughout.
This hybrid differs from N. fusca in the presence of bristles on the underside of the lid. Conversely, it has a dense 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...
on the stem and at the margins of the lamina, compared to the virtually glabrous stem and leaves of N. lowii. It also differs from N. lowii in having a more developed 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...
, which is circular in cross section. While lower pitchers of N. lowii have prominent teeth, those of N. fusca × N. lowii are indistinct. In addition, a glandular appendage is present on the underside of the lid, a trait inherited from N. fusca.
Nepenthes fusca × N. lowii is difficult to confuse with its putative parent species, but is somewhat similar to N. chaniana × N. veitchii
Nepenthes veitchii
Nepenthes veitchii |James Veitch]], nurseryman of the Veitch Nurseries), or Veitch's Pitcher-Plant, is a Nepenthes species from the island of Borneo. The plant is widespread in north-western Borneo and can also be found in parts of Kalimantan. N...
. The latter hybrid can be distinguished on the basis of its peristome, which is wider, more flared, and less cylindrical. In addition, this hybrid has a less ovate lid, which lacks the bristles characteristic of N. lowii, and a denser indumentum covering the stem and leaves.
N. fusca × N. reinwardtiana
A putative cross between N. fusca and N. reinwardtianaNepenthes reinwardtiana
Nepenthes reinwardtiana , Reinwardt's Pitcher-Plant, is a Nepenthes species found on the islands of Borneo and Sumatra. Although some sources have included Peninsular Malaysia and Singapore within the range of this species, these records appear to be erroneous.Nepenthes reinwardtiana has an...
has been recorded. N. naquiyuddinii is generally thought to be a heterotypic synonym of N. reinwardtiana, but may also represent this hybrid, as both putative parent species grow in close proximity to it.
N. fusca × N. stenophylla
This hybrid is known from the eastern slopes of Mount Trus MadiMount Trus Madi
Mount Trus Madi or Trusmadi is Malaysia's second highest mountain at . It lies in the state of Sabah, close to Mount Kinabalu. The mountain supports a wide range of unique flora and fauna, perhaps most notably Nepenthes macrophylla, a species of pitcher plant.The natural hybrid Nepenthes ×...
, where it grows in lower montane forest. Both N. fusca and N. stenophylla
Nepenthes stenophylla
Nepenthes stenophylla , or the Narrow-Leaved Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. The species produces attractive funnel-shaped pitchers up to 25 cm high...
are common in this area. It has also been recorded from the Mamut copper mine. It more closely resembles N. stenophylla, but differs in the shape of the lid, which is more oval-shaped.
N. fusca × N. tentaculata
Nepenthes fusca × N. tentaculataNepenthes tentaculata
Nepenthes tentaculata , or the Fringed Pitcher-Plant, is a tropical pitcher plant with a very wide distribution across Borneo and Sulawesi...
was discovered by Linus Gokusing near the summit of Mount Alab, where it grows in upper montane forest at elevations of around 1800 to 2000 m. It is sympatric with both parent species, which are abundant in the area.
Other hybrids
In addition, crosses with N. platychilaNepenthes platychila
Nepenthes platychila is a species of pitcher plant endemic to the Hose Mountains of central Sarawak. It is notable for its smooth peristome and funnel-shaped upper pitchers....
, N. rajah
Nepenthes rajah
Nepenthes rajah is an insectivorous pitcher plant species of the Nepenthaceae family. It is endemic to Mount Kinabalu and neighbouring Mount Tambuyukon in Sabah, Malaysian Borneo. Nepenthes rajah grows exclusively on serpentine substrates, particularly in areas of seeping ground water where the...
, and N. veitchii
Nepenthes veitchii
Nepenthes veitchii |James Veitch]], nurseryman of the Veitch Nurseries), or Veitch's Pitcher-Plant, is a Nepenthes species from the island of Borneo. The plant is widespread in north-western Borneo and can also be found in parts of Kalimantan. N...
have been recorded.
The pitchers of N. hurrelliana
Nepenthes hurrelliana
Nepenthes hurrelliana is a tropical pitcher plant endemic to Borneo, where it has been recorded from northern Sarawak, southwestern Sabah, and Brunei. It is of putative hybrid origin; its two original parent species are thought to be N. fusca and N. veitchii...
are roughly intermediate in appearance between those of N. fusca and N. veitchii
Nepenthes veitchii
Nepenthes veitchii |James Veitch]], nurseryman of the Veitch Nurseries), or Veitch's Pitcher-Plant, is a Nepenthes species from the island of Borneo. The plant is widespread in north-western Borneo and can also be found in parts of Kalimantan. N...
. This has led to speculation regarding the lineage of this species, with a number of authors suggesting a possible hybridogenic origin. However, N. hurrelliana is distinct from the natural hybrid N. fusca × N. veitchii and most authors now regard it as a valid species.
Cultivation
Carnivorous Plant Newsletter
The Carnivorous Plant Newsletter is the official publication of the International Carnivorous Plant Society , the largest such organization in the world.-History and editorship:...
, summarising measured tolerances of several highland Nepenthes species based on experiments conducted between 1996 and 2001.
Sacilotto found N. fusca to be tolerant of a wide range of conditions; with the exception of plants not treated with fungicide
Fungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
s, no test groups showed a survival rate
Survival rate
In biostatistics, survival rate is a part of survival analysis, indicating the percentage of people in a study or treatment group who are alive for a given period of time after diagnosis...
of less than 75%. Nepenthes fusca was found to tolerate temperatures in the range of 10 to 38 °C (50 to 100.4 F). A nighttime drop in temperature below 21 °C (69.8 °F) was necessary for good growth; plants that were not exposed to such a drop grew poorly and produced fewer pitchers. The experiments suggested that N. fusca grows best when relative humidity
Relative humidity
Relative humidity is a term used to describe the amount of water vapor in a mixture of air and water vapor. It is defined as the partial pressure of water vapor in the air-water mixture, given as a percentage of the saturated vapor pressure under those conditions...
is in the range of 65 to 90%.
The species seemed to do best in growing media with a high proportion of organic matter
Organic matter
Organic matter is matter that has come from a once-living organism; is capable of decay, or the product of decay; or is composed of organic compounds...
(such as a mixture consisting of 10% peat moss chunks, 30% perlite
Perlite
Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently...
, and 60% of any combination of Sphagnum
Sphagnum
Sphagnum is a genus of between 151 and 350 species of mosses commonly called peat moss, due to its prevalence in peat bogs and mires. A distinction is made between sphagnum moss, the live moss growing on top of a peat bog on one hand, and sphagnum peat moss or sphagnum peat on the other, the...
moss
Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
and fir
Fir
Firs are a genus of 48–55 species of evergreen conifers in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range...
bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
). Soil with a slightly 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 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 4.5 to 5.0 produced the best results. Optimal soil conductivity appeared to lie between 10 and 45 microsiemens
Siemens (unit)
The siemens is the SI derived unit of electric conductance and electric admittance. Conductance and admittance are the reciprocals of resistance and impedance respectively, hence one siemens is equal to the reciprocal of one ohm, and is sometimes referred to as the mho. In English, the term...
.
An illuminance
Illuminance
In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of the intensity of the incident light, wavelength-weighted by the luminosity function to correlate with human brightness perception. Similarly, luminous emittance is the luminous flux per...
of 6400–8600 lx
Lux
The lux is the SI unit of illuminance and luminous emittance, measuring luminous flux per unit area. It is used in photometry as a measure of the intensity, as perceived by the human eye, of light that hits or passes through a surface...
(600–800 fc
Foot-candle
A foot-candle is a non-SI unit of illuminance or light intensity widely used in photography, film, television, conservation lighting, and the lighting industry...
) proved to be optimal when plants were grown under sunlight, high pressure sodium
Sodium vapor lamp
A sodium vapor lamp is a gas discharge lamp that uses sodium in an excited state to produce light. There are two varieties of such lamps: low pressure and high pressure...
, and metal halide lamp
Metal halide lamp
Metal-halide lamps, a member of the high-intensity discharge family of lamps, produce high light output for their size, making them a compact, powerful, and efficient light source. By adding rare earth metal salts to the mercury vapor lamp, improved luminous efficacy and light color is obtained...
s. However, specimens placed under an even combination of Gro-Lux and cool white fluorescent lamp
Fluorescent lamp
A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful...
s at 5400–7500 lx (500–700 fc) exhibited the most vibrant colours (although growth rates remained the same). Plants moved from the former to the latter light set up showed a significant change in pigmentation; green leaf blades turned bronzy and speckles on the pitchers darkened markedly.
Nepenthes fusca was found to respond well to a quarter-strength fertilizer
Fertilizer
Fertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
that was applied to the pitchers. Ant
Ant
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 were also an effective food source.
External links
- Nepenthes fusca at ARKiveARKiveARKive is a global initiative with the mission of "promoting the conservation of the world's threatened species, through the power of wildlife imagery", which it does by locating and gathering films, photographs and audio recordings of the world's species into a centralised digital archive. Its...