Nepenthes neoguineensis
Encyclopedia
Nepenthes neoguineensis (icon) is a tropical pitcher plant
native to the island of New Guinea
, after which it is named.
, New Guinea
. Two further collections were made by Gerard Martinus Versteeg on June 19 and September 25, 1907. N. neoguineensis was again collected on May 10, 1910, by Knud Gjellerup.
The first name applied to this species was Nepenthes leptoptera by Hermann Zippel in 1900. However, this name is not valid as it only appeared on the label of a herbarium specimen (HLB.908.154-597) deposited at the National Herbarium of the Netherlands
in Leiden. The specimen was collected from New Guinea.
Nepenthes neoguineensis was described by John Muirhead Macfarlane
in 1911 based on the specimen Versteeg 1746, which consists of female plant material.
In 1916, Henry Nicholas Ridley
described what he believed represented a male plant of N. neoguineensis. However, in his seminal monograph "The Nepenthaceae of the Netherlands Indies
", B. H. Danser
showed that it belonged to a closely related but distinct species, which he named N. papuana
.
s. Internodes are up to 4 cm long.
Leaves are chartaceous and petiolate. The lamina is lanceolate and reaches 25 cm in length and 4.5 cm in width. It has an acute apex and is gradually or rather abruptly attenuate towards the base. Three or four indistinct longitudinal veins are present on either side of the midrib. Pinnate veins ascend obliquely from the midrib and are irregularly reticulate in the outer part of the lamina. Tendril
s are up to 4 mm thick and about as long as the lamina.
Upper pitchers gradually arise from the ends of the tendrils, forming a 7 to 23 mm wide curve. They are infundibulate in the lower part, somewhat ventricose at two-fifths of their height, and widened towards the mouth. A pair of fringed wings (≤8 mm wide) runs down the entire length of the pitcher. The pitcher mouth is oblique and acuminate towards the lid. The peristome
is cylindrical or flattened and up to 1.5 mm wide. The glandular region covers the lower third of the inner surface of the pitcher. The glands occur at a density of about 700 to 900 per square centimetre. The lid is suborbicular, truncate or slightly emarginate, and rounded or slightly cordate at the base. Round, depressed glands are present on the undersurface of the lid, being concentrated and increasing in size towards the middle. A flattened, unbranched spur
(≤3 mm long) is inserted at the base of the lid.
The male inflorescence
is a long, cylindrical panicle
. The peduncle
reaches 12 cm in length and 4 mm in width. The rachis
is attenuate and up to 44 cm long. Pedicels
lack bract
eoles, reach 55 mm in length, and are one- to four-flowered. Tepal
s are orbicular-elliptical and around 4 mm long. Stamen
s are about 4 mm long, including the anthers.
The female inflorescence is a panicle-like raceme
. The peduncle may be up to 15 cm long and 2.5 mm wide. The rachis is attenuate and reaches 20 cm in length. Pedicels are up to 35 mm long and most have filiform bracteoles. They are one- to three-flowered. Tepals are oblong-lanceolate and approximately 4 mm long. The ovary is sessile.
Nepenthes neoguineensis has a very sparse indumentum
. The stem is virtually glabrous, as is the lamina. Tendrils are densely hirsute when young, becoming only hairy near the pitcher or entirely glabrous when mature. Pitchers have a dense covering of caducous stellate hairs. The exception is the spur, which has persistent stellate hairs. Inflorescences have a very dense indumentum of short, white or brownish stellate hairs. The pedicels, tepals and the ovary are very densely stellate-tomentose.
Lower pitchers range in colour from light green to dark purple throughout. Upper pitchers are generally yellowish-green, often with a darker peristome and bright red lid. Herbarium specimens are fallow-dun in colour.
Nepenthes neoguineensis is native to New Guinea
and the nearby D'Entrecasteaux Islands
. The species is relatively widespread in the former, ranging across the entire length of the island and occurring in both Papua New Guinea
and the Indonesia
n portion of the island (Western New Guinea
). As such, its conservation status
is listed as Least Concern
on the 2006 IUCN Red List of Threatened Species
.
Nepenthes neoguineensis grows on river edges, river gravel bars, ridge crests, and rarely in open grassland
or disturbed forest. It has a wide altitudinal distribution, occurring from sea-level to an elevation of 900 or even 1400 m.
In the wild, N. neoguineensis occurs sympatrically with N. ampullaria
and N. maxima
.
Danser considered N. tomoriana
from Sulawesi
and N. distillatoria
from Sri Lanka
to be the closest relatives of N. neoguineensis. He also noted its similarity to N. papuana
, stating: "N. papuana is so much alike N. neoguineensis in its vegetative parts, that only the complete knowledge of the generative parts has suggested me to establish a new species".
The two taxa
can be distinguished on the basis of several morphological features. N. papuana has a racemose
inflorescence, while that of N. neoguineensis is a panicle
or panicle-like raceme. Furthermore, the inflorescence of N. papuana usually bears only one-flowered pedicels
, both in male and female plants. Those of N. neoguineensis can be up to four-flowered.
The lamina of N. papuana has very distinct longitudinal veins and indistinct pinnate veins, whereas in N. neoguineensis the opposite is true. In addition, the leaves of N. papuana are very densely ciliate, much more so than in N. neoguineensis. The wings are less developed in the upper pitchers of N. papuana and the fringe elements are more closely spaced.
Based on the structure of its inflorescence, it has been suggested that N. neoguineensis belongs to a group of relatively primitive Nepenthes species, which includes N. distillatoria
and N. pervillei
.
and N. maxima
. The hybrid plants are generally intermediate in appearance between their parent species.
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...
native to the island of 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...
, after which it is named.
Botanical history
Nepenthes neoguineensis was first collected in 1828 by Alexander Zipelius near Triton BayTriton Bay
Triton Bay is an Arctic waterway in Qikiqtaaluk Region, Nunavut, Canada. It is located in Norwegian Bay off Devon Island's Grinnell Peninsula. Bere Bay is to the northwest....
, 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...
. Two further collections were made by Gerard Martinus Versteeg on June 19 and September 25, 1907. N. neoguineensis was again collected on May 10, 1910, by Knud Gjellerup.
The first name applied to this species was Nepenthes leptoptera by Hermann Zippel in 1900. However, this name is not valid as it only appeared on the label of a herbarium specimen (HLB.908.154-597) 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. The specimen was collected from New Guinea.
Nepenthes neoguineensis was described by John Muirhead Macfarlane
John Muirhead Macfarlane
John Muirhead Macfarlane was a Scottish botanist. He was born and educated in Scotland, where he occupied several different academic positions at the University of Edinburgh before emigrating to the United States to assume a professorial chair at the University of Pennsylvania in 1893. He held...
in 1911 based on the specimen Versteeg 1746, which consists of female plant material.
In 1916, Henry Nicholas Ridley
Henry Nicholas Ridley
Henry Nicholas Ridley CMG , MA , FRS, FLS, F.R.H.S. was an English botanist and geologist.Born at West Harling Hall, Norfolk, England...
described what he believed represented a male plant of N. neoguineensis. However, 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...
", B. H. Danser
B. H. Danser
Benedictus Hubertus Danser , often abbreviated B. H. Danser, was a Dutch taxonomist and botanist...
showed that it belonged to a closely related but distinct species, which he named N. papuana
Nepenthes papuana
Nepenthes papuana is a tropical pitcher plant endemic to New Guinea. The specific epithet papuana is derived from Papua, an alternative name for the island.-Botanical history:...
.
Description
Nepenthes neoguineensis is a climbing plant. The stem is up to 6 mm thick and cylindrical to obtusely angular in cross section, especially in the upper part of the internodePlant 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. Internodes are up to 4 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 4 mm thick and about as long as the lamina.
Upper pitchers gradually arise from the ends of the tendrils, forming a 7 to 23 mm wide curve. They are infundibulate in the lower part, somewhat ventricose at two-fifths of their height, and widened towards the mouth. A pair of fringed wings (≤8 mm wide) runs down the entire length of the pitcher. The pitcher mouth is oblique and acuminate towards the lid. 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 cylindrical or flattened and up to 1.5 mm wide. The glandular region covers the lower third of the inner surface of the pitcher. The glands occur at a density of about 700 to 900 per square centimetre. The lid is suborbicular, truncate or slightly emarginate, and rounded or slightly cordate at the base. Round, depressed glands are present on the undersurface of the lid, being concentrated and increasing in size towards the middle. A flattened, unbranched spur
Spur (biology)
A spur in botany is a spike, usually part of a flower.In certain plants, part of a sepal or petal develops into an elongated hollow spike extending behind the flower, containing nectar which is sucked by long-tongued animals . Plants with such structures include Delphinium, Aquilegia, Piperia, and...
(≤3 mm long) is inserted at the base of the lid.
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...
is a long, cylindrical panicle
Panicle
A panicle is a compound raceme, a loose, much-branched indeterminate inflorescence with pedicellate flowers attached along the secondary branches; in other words, a branched cluster of flowers in which the branches are racemes....
. 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...
reaches 12 cm in length and 4 mm in width. 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 attenuate and up to 44 cm long. 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....
lack 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...
eoles, reach 55 mm in length, and are one- to four-flowered. 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-elliptical and around 4 mm long. Stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...
s are about 4 mm long, including the anthers.
The female inflorescence is a panicle-like raceme
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...
. The peduncle may be up to 15 cm long and 2.5 mm wide. The rachis is attenuate and reaches 20 cm in length. Pedicels are up to 35 mm long and most have filiform bracteoles. They are one- to three-flowered. Tepals are oblong-lanceolate and approximately 4 mm long. The ovary is sessile.
Nepenthes neoguineensis has a very sparse 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...
. The stem is virtually glabrous, as is the lamina. Tendrils are densely hirsute when young, becoming only hairy near the pitcher or entirely glabrous when mature. Pitchers have a dense covering of caducous stellate hairs. The exception is the spur, which has persistent stellate hairs. Inflorescences have a very dense indumentum of short, white or brownish stellate hairs. The pedicels, tepals and the ovary are very densely stellate-tomentose.
Lower pitchers range in colour from light green to dark purple throughout. Upper pitchers are generally yellowish-green, often with a darker peristome and bright red lid. Herbarium specimens are fallow-dun in colour.
Ecology
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 nearby D'Entrecasteaux Islands
D'Entrecasteaux Islands
D'Entrecasteaux Islands are situated near the eastern tip of New Guinea in the Solomon Sea in Milne Bay Province of Papua New Guinea. The group spans a distance of 160 km, has a total land area of approximately 3,100 km² and is separated from the Papua New Guinea mainland by the...
. The species is relatively widespread in the former, ranging across the entire length of the island and occurring in both Papua New Guinea
Papua New Guinea
Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
and the 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...
n portion of the island (Western New Guinea
Western New Guinea
West Papua informally refers to the Indonesian western half of the island of New Guinea and other smaller islands to its west. The region is officially administered as two provinces: Papua and West Papua. The eastern half of New Guinea is Papua New Guinea.The population of approximately 3 million...
). As such, its 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...
is listed as Least Concern
Least Concern
Least Concern is an IUCN category assigned to extant taxon or lower taxa which have been evaluated but do not qualify for any other category. As such they do not qualify as threatened, Near Threatened, or Conservation Dependent...
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...
.
Nepenthes neoguineensis grows on river edges, river gravel bars, ridge crests, and rarely in open grassland
Grassland
Grasslands are areas where the vegetation is dominated by grasses and other herbaceous plants . However, sedge and rush families can also be found. Grasslands occur naturally on all continents except Antarctica...
or disturbed forest. It has a wide altitudinal distribution, occurring from sea-level to an elevation of 900 or even 1400 m.
In the wild, N. neoguineensis occurs sympatrically with N. ampullaria
Nepenthes ampullaria
Nepenthes ampullaria , the Flask-Shaped Pitcher-Plant, is a very distinctive and widespread species of Nepenthes, present in Borneo, Sumatra, Thailand, Peninsular Malaysia, Singapore, the Maluku Islands, and New Guinea...
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....
.
Related species
Nepenthes tomoriana
Nepenthes tomoriana is a species of pitcher plant endemic to Sulawesi, where it grows at an elevation of 0–500 m above sea level.-References:...
from 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...
and N. distillatoria
Nepenthes distillatoria
Nepenthes distillatoria is a tropical pitcher plant endemic to Sri Lanka. It was the second Nepenthes species to be described in print and the first to be formally named under the Linnaean system of taxonomy...
from Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
to be the closest relatives of N. neoguineensis. He also noted its similarity to N. papuana
Nepenthes papuana
Nepenthes papuana is a tropical pitcher plant endemic to New Guinea. The specific epithet papuana is derived from Papua, an alternative name for the island.-Botanical history:...
, stating: "N. papuana is so much alike N. neoguineensis in its vegetative parts, that only the complete knowledge of the generative parts has suggested me to establish a new species".
The two 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...
can be distinguished on the basis of several morphological features. N. papuana 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, while that of N. neoguineensis is a panicle
Panicle
A panicle is a compound raceme, a loose, much-branched indeterminate inflorescence with pedicellate flowers attached along the secondary branches; in other words, a branched cluster of flowers in which the branches are racemes....
or panicle-like raceme. Furthermore, the inflorescence of N. papuana usually bears only 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....
, both in male and female plants. Those of N. neoguineensis can be up to four-flowered.
The lamina of N. papuana has very distinct longitudinal veins and indistinct pinnate veins, whereas in N. neoguineensis the opposite is true. In addition, the leaves of N. papuana are very densely ciliate, much more so than in N. neoguineensis. The wings are less developed in the upper pitchers of N. papuana and the fringe elements are more closely spaced.
Based on the structure of its inflorescence, it has been suggested that N. neoguineensis belongs to a group of relatively primitive Nepenthes species, which includes N. distillatoria
Nepenthes distillatoria
Nepenthes distillatoria is a tropical pitcher plant endemic to Sri Lanka. It was the second Nepenthes species to be described in print and the first to be formally named under the Linnaean system of taxonomy...
and N. pervillei
Nepenthes pervillei
Nepenthes pervillei is a tropical pitcher plant endemic to the Seychelles, specifically the islands of Mahé and Silhouette. It grows in rocky areas near granitic mountain summits at elevations of between 350 and 750 m above sea level....
.
Natural hybrids
Where their ranges overlap, N. neoguineensis is known to hybridise with N. ampullariaNepenthes ampullaria
Nepenthes ampullaria , the Flask-Shaped Pitcher-Plant, is a very distinctive and widespread species of Nepenthes, present in Borneo, Sumatra, Thailand, Peninsular Malaysia, Singapore, the Maluku Islands, and New Guinea...
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....
. The hybrid plants are generally intermediate in appearance between their parent species.
External links
- Danser, B.H. 1928. 30. Nepenthes neoguineensis MACF. In: The Nepenthaceae of the Netherlands IndiesThe 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...
. Bulletin du Jardin Botanique de Buitenzorg, Série III, 9(3–4): 249–438. - Nepenthes neoguineensis in its natural habitat