Nepenthes hamata
Encyclopedia
Nepenthes hamata is a tropical pitcher plant
endemic to Sulawesi
, where it grows at elevations of 1400–2500 m above sea level.
The specific epithet hamata is derived from the Latin
word hamatus, meaning "hooked". It describes the appearance of the highly developed peristome
teeth of this species.
explorers many decades before its formal description and recognition by science. Dutch
botanist Pierre Joseph Eyma
collected herbarium
material of this species as early as 1938; this would later be used to designate a type specimen.
In 1984, two formal descriptions
of this species were published in close succession: Shigeo Kurata
described it under the name N. dentata in The Gardens' Bulletin Singapore, while John R. Turnbull and Anne T. Middleton called it N. hamatus in the journal Reinwardtia.
As explained in the introduction to his describing paper on N. dentata, Kurata first became aware of the species more than a decade earlier, on a 1972 visit to Herbarium Bogoriense:
The name N. dentata was first published in Kurata's 1976 guide, Nepenthes of Mount Kinabalu
, where it was included in a table of all Nepenthes species known at the time and asterisked with the note "Not yet established".
and N. glabrata / N. rubromaculata
, which were described by the same three authors.
Nepenthes hamata (emended with a feminine suffix
to match the gender
of Nepenthes) gained greater currency and was said to have been published 21 days prior to N. dentata. However, in 1994 Matthew Jebb
wrote that the "priority of this name over N. dentata [...] is in fact in serious doubt, since the 'preprinted' Reinwardtia issue was technically not 'freely available' in terms of the Botanical Code". Taxonomist Jan Schlauer determined that the publication of Turnbull and Middleton's paper preceded Kurata's formal description of N. dentata in The Gardens' Bulletin Singapore, but came after Kurata's article about the species in the Journal of Insectivorous Plant Society
. While some authors referred to the species as N. dentata in the following years, the name N. hamata enjoyed greater popularity and has for this reason been retained in all major monographs on the genus.
In the years following its description, some authors considered the two taxa
as separate species and there was even speculation among growers that N. hamata represented a hybrid involving the "true" species, N. dentata. Schlauer considers N. dentata to be a heterotypic synonym of N. hamata.
(at the coordinates 1°07′S 121°39′E), at an altitude of 1850–1900 m, on September 19, 1983. In their description of the species, Turnbull and Middleton indicated that the type material had been deposited at Herbarium Bogoriense (BO), the herbarium of the Bogor Botanical Gardens
. However, Martin Cheek
and Matthew Jebb
were unable to locate it there and, referring collectively to the type material of N. hamata, N. glabrata
, and N. infundibuliformis (which were all described by Turnbull and Middleton in the same paper), wrote that "[n]one of these collections has been found at the herbaria they cite".
An early collection by Dutch
botanist Pierre Joseph Eyma
, designated as Eyma 3572, represents the type material of N. dentata. The specimens of this series were taken from a site on the north spur of Mount Lumut, between bivouacs
II and III, on September 3, 1938. Both the lectotype
and isotype
are deposited at Herbarium Bogoriense (BO).
In addition to the herbarium specimens of N. hamata mentioned here, a number of others have appeared in the literature.
300–400 during this time. The significant commercial value of the species encouraged wild collection by both local and foreign plant hunters. Beginning in 1995, Ch'ien Lee
oversaw a Nepenthes artificial propagation
program at Malesiana Tropicals, a company based in Sarawak
, Malaysian Borneo. Seeds of N. hamata, which had been collected in the wild by Lee, were used to multiply plant material in vitro
in the company's tissue culture laboratory. By 2001, Malesiana Tropicals had a sales inventory of more than 500 individuals of the species, supplying both hobbyists and commercial growers as well as botanical gardens and researchers. The increased supply led to a sharp fall in prices. In 2001, the price of N. hamata was predicted to stabilise at roughly $50 per plant, greatly limiting the incentive for wild collection.
announced the discovery of a new form of N. hamata with an exceptionally dense indumentum
:
In response to subsequent speculation about the plant's taxonomic status, Lee wrote that it "merely represents a geographical variant of N. hamata".
observed N. hamata in the wild and published an updated description of the species in his 2009 monograph, Pitcher Plants of the Old World
. The book also covered the closely related undescribed taxon
N. sp. Sulawesi
, which McPherson had discovered with Greg Bourke in 2007.
, which may be branched, reaches a maximum length of around 7 m. It is terete to obtusely trigonous and varies in diameter from up to 3 mm in rosettes
and short stems, to 4–5 mm in climbing stems. In the former, the internodal length is typically up to 6 mm and in the latter 3.5–6 cm.
In the case of rosettes and short stems, the lamina is typically oblanceolate to oblong-elliptic and measures up to 7.5 cm in length by 2.5 cm in width. It has an acute apex and does not exhibit a peltate tendril attachment. The laminar base is amplexicaul, clasping the stem and giving it a subperfoliate appearance. Auricles
may be present, although their level of development varies. The lamina may be slightly decurrent down the stem, but not prominently so.
Laminae produced on climbing stems are predominantly oblong-elliptic in shape, but may rarely be lanceolate. They are larger than those borne on shorter stems, but nonetheless relatively short, measuring 5–15 cm in length by 1.8–4 cm in width. The laminar apex may be acute to obtuse, while the base is abruptly contracted and clasps the stem; it may be decurrent for up to 1.5 cm in some populations. Two (rarely up to four) longitudinal veins are present on either side of the midrib. They are restricted to the outer third to half (rarely up to two-thirds) of the laminar surface. Pinnate veins are inconspicuous; they are patent and branching.
The pitcher mouth is often distinctly rhomboid in shape, but may also be oval or elliptic. It has a highly oblique insertion and is concave when viewed in profile. The mouth rises at the rear to form a tapered neck, which may be held upright or be inclined forward over the pitcher orifice. The species is noted for having possibly the most developed peristome
in the genus. It is cylindrical to slightly flattened, glossy, rigid, and up to 5 mm wide (excluding the teeth). It consists of expanded ribs up to 6 mm high and spaced up to 5 mm apart. The entire flanges can measure up to 15 mm in length, although their size and number differ between populations (a typical number being approximately 20 on each side of the orifice). These flanges form exceptionally long, incurved teeth at the inner edge of the pitcher orifice. The teeth are sickle-shaped (falcate) and extend approximately 7 mm into the interior, as measured from the inner edge of the peristome to the tooth apex. The outer edge of the peristome is entire, with the recurved flanges extending for around 2 mm past the rim. The teeth of the neck may assume a dagger-like shape and measure up to 10 mm by 2 mm. These uppermost teeth are often noticeably splayed forward.
The pitcher lid or operculum
is elliptic to ovate and measures up to 6 cm in length by 5 cm in width. It is held roughly horizontally and often has upturned margins. The apex is rounded, whereas the base is occasionally cordate or subcordate. No appendages are present on the lower surface, but multicellular filiform appendages may be found on the upper surface, though this feature is often unstable and may be absent altogether. These 'hairs' or 'tentacles' are up to 20 mm long and may be branched. They arise from the ends of the lid veins and may number as many as 45 on each side of the lid. They are mainly restricted to the outer margins of the lid, where they are around 3 rows deep. The lower surface of the lid bears sparsely distributed nectar glands in the form of shortly elliptic, bordered pits. These are very small and inconspicuous, measuring only 0.1–0.2 mm in diameter. A spur up to 9 mm long is inserted near the base of the lid. It may be simple or repeatedly branched to the point of being fasciculate. The herbarium material examined by Cheek and Jebb exhibited spurs that were basally 5-branched, with each branch being secondarily ramified.
Upper pitchers are similar in shape to their terrestrial counterparts, though usually more elongated, growing to 7–25 cm in height by 1.2–6 cm in width. The basal fifth to third of the trap is ovate, narrowing and becoming cylindrical to slightly infundibular above. As in lower pitchers, a conspicuous hip often marks the boundary between these two parts. In most cases, a pair of narrow ribs is present in place of the wings, although fully developed fringed wings are sometimes encountered. The peristome is often even more developed in aerial traps, with longer and more widely spaced teeth, which curve completely outwards in some populations. These teeth are usually 12–16 mm long by 2–3 mm high, and spaced 2.5–6 mm apart. Upper pitchers resemble lower ones in most other respects.
inflorescence
. The male inflorescence is 8–15 cm long, of which the peduncle
constitutes 2.4–10 cm and the rachis
up to 8 cm. The peduncle has a basal diameter of around 3 mm. Flowers are borne solitarily on ebracteate pedicels
measuring 10–15 mm in length by 0.1–0.3 mm in width. The pedicels number around 22 per inflorescence. Tepal
s are elliptic, reflexed, and 1.5–3 mm long by 1–1.5 mm wide. Androphores are 1–2.5 mm long and bear anther heads measuring 0.6–0.8 mm by 0.8–1.4 mm. One infructescence
was measured at 8.5 cm long by roughly 5 cm wide (fruits included), with a peduncle measuring 6.5 cm in length and having a basal diameter of 2.25 mm. Fruit
s number around 15 per infructescence and bear valves 19–20 mm long by 3.5–4.5 mm wide. As in most Nepenthes species, the seed
s are filiform. They are around 8 mm long by 0.4–0.6 mm wide.
is highly variable. Most populations are predominantly glabrous, having soft orange to brown hairs only on developing pitchers, tendrils, and the underside of the midrib. Certain forms also have extremely long, dense, and shaggy hair covering their pitchers and parts of the inflorescence. Conversely, some plants may lack hairs altogether on mature parts.
Despite the variation between populations, no infraspecific taxa of N. hamata have been described.
n island of Sulawesi
. It has been recorded primarily from the eastern portion of Central Sulawesi
province
(including large parts of the East Peninsula), but more northerly populations from the Minahassa Peninsula are also known. Specifically, N. hamata has been recorded from, among other locations, Mount Lumut (the locus classicus of the species), Mount Poka Pindjang, Mount Roroda Timbu, Mount Sojol, Mount Tambusisi, and the Tomongkobae Mountains. The species has a known altitudinal distribution of 1400–2500 m above sea level.
Nepenthes hamata may grow terrestrially or as an epiphyte
. It is found in lower and upper montane mossy forest and among scrub
vegetation on mountain ridges and summits. In such habitats it experiences high relative humidity
and often partially shady conditions. It is known to occasionally form natural hybrids with N. glabrata
and N. tentaculata
. The wild cross with N. glabrata was first reported by Ch'ien Lee
in December 2006.
The conservation status
of N. hamata is listed as Vulnerable
on the IUCN Red List
, based on an assessment carried out in 2000. In 2009, Stewart McPherson
wrote that the species is "widespread" across its range and that most populations are "remote and not generally threatened at present". Nepenthes hamata is known from at least two protected area
s (Lore Lindu National Park
and Morowali Nature Reserve), although the full extent of its range is unknown and it is likely to occur on a number of as yet unexplored peaks. McPherson emphasised the need to monitor populations of specific variants, particularly the red hairy form, because "[l]oss of diversity [...] may become a legitimate concern in the future as a result of collection pressures".
and Sulawesi
: N. glabrata
, N. muluensis
, N. murudensis
, and N. tentaculata
. More recently, N. sp. Sulawesi
has joined this group of related taxa. In their 2001 monograph, "Nepenthaceae
", Martin Cheek
and Matthew Jebb
also suggested a close relative in the Sumatra
n species N. adnata
.
Nepenthes hamata is very closely allied to N. tentaculata. It shares with this species the multicellular filiform appendages of the upper lid, as well as the general form of its laminae and pitchers. Nepenthes hamata clearly differs from N. tentaculata in the development of its peristome, which bears exaggerated flange-like extensions; N. tentaculata lacks conspicuous teeth altogether.
In their 2001 monograph, Martin Cheek
and Matthew Jebb
wrote that although the available herbarium material of N. hamata (around seven collections at the time) showed wide variation in peristome development, with some specimens appearing "very close to N. tentaculata", this did not represent a continuum of intergrades between N. hamata at one extreme and N. tentaculata at the other, but rather was due to a combination of lower and upper pitchers (the latter having more highly developed peristome teeth).
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 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...
, where it grows at elevations of 1400–2500 m above sea level.
The specific epithet hamata 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 hamatus, meaning "hooked". It describes the appearance of the highly 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...
teeth of this species.
Early history and formal descriptions
Nepenthes hamata was first encountered by WesternWestern world
The Western world, also known as the West and the Occident , is a term referring to the countries of Western Europe , the countries of the Americas, as well all countries of Northern and Central Europe, Australia and New Zealand...
explorers many decades before its formal description and recognition by science. 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 Pierre Joseph Eyma
Pierre Joseph Eyma
Pierre Joseph Eyma was a Dutch botanist.Eyma was born in Maarssen, the Netherlands, in 1903. He studied at Utrecht University and served as an assistant at the university's herbarium between 1929 and 1937. Eyma earned a doctorate in 1932 for a taxonomic thesis on Surinamese plants...
collected 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...
material of this species as early as 1938; this would later be used to designate a type specimen.
In 1984, two formal descriptions
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...
of this species were published in close succession: 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....
described it under the name N. dentata in The Gardens' Bulletin Singapore, while John R. Turnbull and Anne T. Middleton called it N. hamatus in the journal Reinwardtia.
As explained in the introduction to his describing paper on N. dentata, Kurata first became aware of the species more than a decade earlier, on a 1972 visit to Herbarium Bogoriense:
The name N. dentata was first published in Kurata's 1976 guide, Nepenthes of Mount Kinabalu
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...
, where it was included in a table of all Nepenthes species known at the time and asterisked with the note "Not yet established".
Questions over nomenclatural priority
The formal descriptions of N. dentata by Kurata and N. hamatus by Turnbull and Middleton were published almost concurrently, leading to uncertainty over which name held nomenclatural priority. A similar situation surrounded the publication of N. eymae / N. infundibuliformisNepenthes 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. glabrata / N. rubromaculata
Nepenthes glabrata
Nepenthes glabrata is a tropical pitcher plant endemic to Sulawesi. The species grows in open, high forest at elevations of 1600 to 2100 m. It produces dainty, colourful pitchers reaching only a few centimetres in height...
, which were described by the same three authors.
Nepenthes hamata (emended with a feminine suffix
Suffix
In linguistics, a suffix is an affix which is placed after the stem of a word. Common examples are case endings, which indicate the grammatical case of nouns or adjectives, and verb endings, which form the conjugation of verbs...
to match the gender
Grammatical gender
Grammatical gender is defined linguistically as a system of classes of nouns which trigger specific types of inflections in associated words, such as adjectives, verbs and others. For a system of noun classes to be a gender system, every noun must belong to one of the classes and there should be...
of Nepenthes) gained greater currency and was said to have been published 21 days prior to N. dentata. However, in 1994 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....
wrote that the "priority of this name over N. dentata [...] is in fact in serious doubt, since the 'preprinted' Reinwardtia issue was technically not 'freely available' in terms of the Botanical Code". Taxonomist Jan Schlauer determined that the publication of Turnbull and Middleton's paper preceded Kurata's formal description of N. dentata in The Gardens' Bulletin Singapore, but came after Kurata's article about the species in the Journal of Insectivorous Plant Society
Journal of Insectivorous Plant Society
The is a quarterly Japanese-language periodical and the official publication of the Insectivorous Plant Society of Japan. The journal was established in January 1950. As of 2010, it is published in A4 format and totals around 120 pages annually...
. While some authors referred to the species as N. dentata in the following years, the name N. hamata enjoyed greater popularity and has for this reason been retained in all major monographs on the genus.
In the years following its description, some authors considered 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...
as separate species and there was even speculation among growers that N. hamata represented a hybrid involving the "true" species, N. dentata. Schlauer considers N. dentata to be a heterotypic synonym of N. hamata.
Type material
The type specimen of N. hamata is J.R.Turnbull & A.T.Middleton 83121a, which was collected from the west ridge of Mount Lumut, Central SulawesiCentral Sulawesi
Central Sulawesi is a province of Indonesia located in the centre of Sulawesi. It was established on 13 April 1964....
(at the coordinates 1°07′S 121°39′E), at an altitude of 1850–1900 m, on September 19, 1983. In their description of the species, Turnbull and Middleton indicated that the type material had been deposited at Herbarium Bogoriense (BO), the herbarium 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...
. However, 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,...
and 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....
were unable to locate it there and, referring collectively to the type material of N. hamata, N. glabrata
Nepenthes glabrata
Nepenthes glabrata is a tropical pitcher plant endemic to Sulawesi. The species grows in open, high forest at elevations of 1600 to 2100 m. It produces dainty, colourful pitchers reaching only a few centimetres in height...
, and N. infundibuliformis (which were all described by Turnbull and Middleton in the same paper), wrote that "[n]one of these collections has been found at the herbaria they cite".
An early collection 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 Pierre Joseph Eyma
Pierre Joseph Eyma
Pierre Joseph Eyma was a Dutch botanist.Eyma was born in Maarssen, the Netherlands, in 1903. He studied at Utrecht University and served as an assistant at the university's herbarium between 1929 and 1937. Eyma earned a doctorate in 1932 for a taxonomic thesis on Surinamese plants...
, designated as Eyma 3572, represents the type material of N. dentata. The specimens of this series were taken from a site on the north spur of Mount Lumut, between bivouacs
Bivouac shelter
A bivouac traditionally refers to a military encampment made with tents or improvised shelters, usually without shelter or protection from enemy fire or such a site where a camp may be built. It is also commonly used to describe a variety of improvised camp sites such as those used in scouting and...
II and III, on September 3, 1938. Both the lectotype
Lectotype
In botanical nomenclature and zoological nomenclature, a lectotype is a kind of name-bearing type. When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype...
and isotype
Isotype
Isotype can refer to:* In crystallography, an "isotype" is a synonym for isomorph* In biology, per the International Code of Botanical Nomenclature, the "isotype" is a duplicate of the holotype....
are deposited at Herbarium Bogoriense (BO).
In addition to the herbarium specimens of N. hamata mentioned here, a number of others have appeared in the literature.
Horticultural interest
Nepenthes hamata remained very rare in cultivation until around 1996. Its scarcity and striking appearance made it particularly desirable to collectors, and individual plants commanded prices of approximately US$United States dollar
The United States dollar , also referred to as the American dollar, is the official currency of the United States of America. It is divided into 100 smaller units called cents or pennies....
300–400 during this time. The significant commercial value of the species encouraged wild collection by both local and foreign plant hunters. Beginning in 1995, 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,...
oversaw a Nepenthes artificial propagation
Micropropagation
Micropropagation is the practice of rapidly multiplying stock plant material to produce a large number of progeny plants, using modern plant tissue culture methods....
program at Malesiana Tropicals, a company based 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...
, Malaysian Borneo. Seeds of N. hamata, which had been collected in the wild by Lee, were used to multiply plant material in vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
in the company's tissue culture laboratory. By 2001, Malesiana Tropicals had a sales inventory of more than 500 individuals of the species, supplying both hobbyists and commercial growers as well as botanical gardens and researchers. The increased supply led to a sharp fall in prices. In 2001, the price of N. hamata was predicted to stabilise at roughly $50 per plant, greatly limiting the incentive for wild collection.
Discovery of hairy variant
In early 2005, Ch'ien LeeCh'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,...
announced the discovery of a new form of N. hamata with an exceptionally 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...
:
In response to subsequent speculation about the plant's taxonomic status, Lee wrote that it "merely represents a geographical variant of N. hamata".
Later developments
British geographer Stewart McPhersonStewart McPherson (geographer)
Stewart R. McPherson is a British geographer.He studied at the University of Durham in England, the University of Tübingen in Germany and Yale University in the United States....
observed N. hamata in the wild and published an updated description of the species in his 2009 monograph, Pitcher Plants of the Old World
Pitcher Plants of the Old World
Pitcher Plants of the Old World is a two-volume monograph by Stewart McPherson on the pitcher plants of the genera Nepenthes and Cephalotus. It was published in May 2009 by Redfern Natural History Productions...
. The book also covered the closely related undescribed taxon
Undescribed taxon
In taxonomy, an undescribed taxon is a taxon that has been discovered, but not yet formally described and named. The various Nomenclature Codes specify the requirements for a new taxon to be validly described and named. Until such a description has been published, the taxon has no formal or...
N. sp. Sulawesi
Nepenthes sp. Sulawesi
Nepenthes sp. Sulawesi is an undescribed tropical pitcher plant endemic to Central Sulawesi, where it grows on at least 5 mountains. It is very similar to both N. hamata and N. tentaculata....
, which McPherson had discovered with Greg Bourke in 2007.
Description
Nepenthes hamata is a strong climber. The stemPlant 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...
, which may be branched, reaches a maximum length of around 7 m. It is terete to obtusely trigonous and varies in diameter from up to 3 mm in rosettes
Rosette (botany)
In botany, a rosette is a circular arrangement of leaves, with all the leaves at a single height.Though rosettes usually sit near the soil, their structure is an example of a modified stem.-Function:...
and short stems, to 4–5 mm in climbing stems. In the former, the internodal length is typically up to 6 mm and in the latter 3.5–6 cm.
Leaves
Leaves are sessile and chartaceous in texture. The shape of the lamina (leaf blade) is variable: it may be linear, lanceolate, or slightly elliptic.In the case of rosettes and short stems, the lamina is typically oblanceolate to oblong-elliptic and measures up to 7.5 cm in length by 2.5 cm in width. It has an acute apex and does not exhibit a peltate tendril attachment. The laminar base is amplexicaul, clasping the stem and giving it a subperfoliate appearance. Auricles
Auricle (botany)
In botany, an auricle is a small ear-like projection from the base of a leaf or petal....
may be present, although their level of development varies. The lamina may be slightly decurrent down the stem, but not prominently so.
Laminae produced on climbing stems are predominantly oblong-elliptic in shape, but may rarely be lanceolate. They are larger than those borne on shorter stems, but nonetheless relatively short, measuring 5–15 cm in length by 1.8–4 cm in width. The laminar apex may be acute to obtuse, while the base is abruptly contracted and clasps the stem; it may be decurrent for up to 1.5 cm in some populations. Two (rarely up to four) longitudinal veins are present on either side of the midrib. They are restricted to the outer third to half (rarely up to two-thirds) of the laminar surface. Pinnate veins are inconspicuous; they are patent and branching.
Pitchers
Rosette and lower pitchers are only produced for a short time before the plant transitions into a scrambling vine (although they may be produced later on offshoots from the original stem). They grow up to 18 cm high by 5 wide. They are ovate in the basal fifth to half of the pitcher cup, being bulbous to varying degrees in this portion, often narrowly so. The pitcher is narrower in the upper part and may be cylindrical or slightly infundibular towards the orifice. The boundary between these two portions is often delineated by a pronounced hip. The ventral face of the pitcher is flattened. A pair of wings up to 16 mm wide runs down the ventral surface of the pitcher cup. These wings bear densely packed filiform fringe elements up to 19 mm long, which commonly exceed the width of the wings themselves. These filaments are often arranged in pairs, spaced around 2 mm apart, and are usually branched dichotomously once or twice.The pitcher mouth is often distinctly rhomboid in shape, but may also be oval or elliptic. It has a highly oblique insertion and is concave when viewed in profile. The mouth rises at the rear to form a tapered neck, which may be held upright or be inclined forward over the pitcher orifice. The species is noted for having possibly the most 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...
in the genus. It is cylindrical to slightly flattened, glossy, rigid, and up to 5 mm wide (excluding the teeth). It consists of expanded ribs up to 6 mm high and spaced up to 5 mm apart. The entire flanges can measure up to 15 mm in length, although their size and number differ between populations (a typical number being approximately 20 on each side of the orifice). These flanges form exceptionally long, incurved teeth at the inner edge of the pitcher orifice. The teeth are sickle-shaped (falcate) and extend approximately 7 mm into the interior, as measured from the inner edge of the peristome to the tooth apex. The outer edge of the peristome is entire, with the recurved flanges extending for around 2 mm past the rim. The teeth of the neck may assume a dagger-like shape and measure up to 10 mm by 2 mm. These uppermost teeth are often noticeably splayed forward.
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 elliptic to ovate and measures up to 6 cm in length by 5 cm in width. It is held roughly horizontally and often has upturned margins. The apex is rounded, whereas the base is occasionally cordate or subcordate. No appendages are present on the lower surface, but multicellular filiform appendages may be found on the upper surface, though this feature is often unstable and may be absent altogether. These 'hairs' or 'tentacles' are up to 20 mm long and may be branched. They arise from the ends of the lid veins and may number as many as 45 on each side of the lid. They are mainly restricted to the outer margins of the lid, where they are around 3 rows deep. The lower surface of the lid bears sparsely distributed nectar glands in the form of shortly elliptic, bordered pits. These are very small and inconspicuous, measuring only 0.1–0.2 mm in diameter. A spur up to 9 mm long is inserted near the base of the lid. It may be simple or repeatedly branched to the point of being fasciculate. The herbarium material examined by Cheek and Jebb exhibited spurs that were basally 5-branched, with each branch being secondarily ramified.
Upper pitchers are similar in shape to their terrestrial counterparts, though usually more elongated, growing to 7–25 cm in height by 1.2–6 cm in width. The basal fifth to third of the trap is ovate, narrowing and becoming cylindrical to slightly infundibular above. As in lower pitchers, a conspicuous hip often marks the boundary between these two parts. In most cases, a pair of narrow ribs is present in place of the wings, although fully developed fringed wings are sometimes encountered. The peristome is often even more developed in aerial traps, with longer and more widely spaced teeth, which curve completely outwards in some populations. These teeth are usually 12–16 mm long by 2–3 mm high, and spaced 2.5–6 mm apart. Upper pitchers resemble lower ones in most other respects.
Inflorescence
Nepenthes hamata has a racemoseRaceme
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 male inflorescence is 8–15 cm long, of which 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...
constitutes 2.4–10 cm and the rachis
Rachis
Rachis is a biological term for a main axis or "shaft".-In zoology:In vertebrates a rachis can refer to the series of articulated vertebrae, which encase the spinal cord. In this case the rachis usually form the supporting axis of the body and is then called the spine or vertebral column...
up to 8 cm. The peduncle has a basal diameter of around 3 mm. Flowers are borne solitarily on ebracteate 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....
measuring 10–15 mm in length by 0.1–0.3 mm in width. The pedicels number around 22 per inflorescence. 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 elliptic, reflexed, and 1.5–3 mm long by 1–1.5 mm wide. Androphores are 1–2.5 mm long and bear anther heads measuring 0.6–0.8 mm by 0.8–1.4 mm. One infructescence
Infructescence
Infructescence is defined as the ensemble of fruits derived from ovaries of an inflorescence, structured according to the inflorescence scheme....
was measured at 8.5 cm long by roughly 5 cm wide (fruits included), with a peduncle measuring 6.5 cm in length and having a basal diameter of 2.25 mm. Fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s number around 15 per infructescence and bear valves 19–20 mm long by 3.5–4.5 mm wide. As in most Nepenthes species, the seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s are filiform. They are around 8 mm long by 0.4–0.6 mm wide.
Indumentum
The extent of the indumentumIndumentum
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...
is highly variable. Most populations are predominantly glabrous, having soft orange to brown hairs only on developing pitchers, tendrils, and the underside of the midrib. Certain forms also have extremely long, dense, and shaggy hair covering their pitchers and parts of the inflorescence. Conversely, some plants may lack hairs altogether on mature parts.
Despite the variation between populations, no infraspecific taxa of N. hamata have been described.
Ecology and conservation
Nepenthes hamata is endemic to the IndonesiaIndonesia
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 island of 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...
. It has been recorded primarily from the eastern portion of Central Sulawesi
Central Sulawesi
Central Sulawesi is a province of Indonesia located in the centre of Sulawesi. It was established on 13 April 1964....
province
Provinces of Indonesia
The province is the highest tier of local government subnational entity in Indonesia. Each province has its own local government, headed by a governor, and has its own legislative body...
(including large parts of the East Peninsula), but more northerly populations from the Minahassa Peninsula are also known. Specifically, N. hamata has been recorded from, among other locations, Mount Lumut (the locus classicus of the species), Mount Poka Pindjang, Mount Roroda Timbu, Mount Sojol, Mount Tambusisi, and the Tomongkobae Mountains. The species has a known altitudinal distribution of 1400–2500 m above sea level.
Nepenthes hamata may grow terrestrially or 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...
. It is found in lower and upper montane mossy forest and among scrub
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
vegetation on mountain ridges and summits. In such habitats it experiences high 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...
and often partially shady conditions. It is known to occasionally form natural hybrids with N. glabrata
Nepenthes glabrata
Nepenthes glabrata is a tropical pitcher plant endemic to Sulawesi. The species grows in open, high forest at elevations of 1600 to 2100 m. It produces dainty, colourful pitchers reaching only a few centimetres in height...
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...
. The wild cross with N. glabrata was first reported by 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,...
in December 2006.
The conservation status
Conservation status
The conservation status of a group of organisms indicates whether the group is still extant and how likely the group is to become extinct in the near future...
of N. hamata is listed 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 IUCN Red List
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. In 2009, Stewart McPherson
Stewart McPherson (geographer)
Stewart R. McPherson is a British geographer.He studied at the University of Durham in England, the University of Tübingen in Germany and Yale University in the United States....
wrote that the species is "widespread" across its range and that most populations are "remote and not generally threatened at present". Nepenthes hamata is known from at least two protected area
Protected area
Protected areas are locations which receive protection because of their recognised natural, ecological and/or cultural values. There are several kinds of protected areas, which vary by level of protection depending on the enabling laws of each country or the regulations of the international...
s (Lore Lindu National Park
Lore Lindu National Park
Lore Lindu National Park is a forested protected area on the Indonesian island of Sulawesi, in the province of Central Sulawesi. The area of the national park is 2,180 km² covering both lowland and montane forests. It provides habitat to numerous rare species, including 77 bird species...
and Morowali Nature Reserve), although the full extent of its range is unknown and it is likely to occur on a number of as yet unexplored peaks. McPherson emphasised the need to monitor populations of specific variants, particularly the red hairy form, because "[l]oss of diversity [...] may become a legitimate concern in the future as a result of collection pressures".
Related species
Nepenthes hamata belongs to what has been called the "Hamata group", which also includes four other closely related species from BorneoBorneo
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....
and 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...
: N. glabrata
Nepenthes glabrata
Nepenthes glabrata is a tropical pitcher plant endemic to Sulawesi. The species grows in open, high forest at elevations of 1600 to 2100 m. It produces dainty, colourful pitchers reaching only a few centimetres in height...
, N. muluensis
Nepenthes muluensis
Nepenthes muluensis , or the Mulu Pitcher-Plant, is a tropical pitcher plant endemic to Borneo. It grows in highland habitats at elevations of 1700 to 2400 m above sea level.-Botanical history:...
, N. murudensis
Nepenthes murudensis
Nepenthes murudensis , or the Murud Pitcher-Plant, is a tropical pitcher plant endemic to Mount Murud in Borneo, after which it is named. It is of putative hybrid origin: its two original parent species are thought to be N. reinwardtiana and N...
, 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...
. More recently, N. sp. Sulawesi
Nepenthes sp. Sulawesi
Nepenthes sp. Sulawesi is an undescribed tropical pitcher plant endemic to Central Sulawesi, where it grows on at least 5 mountains. It is very similar to both N. hamata and N. tentaculata....
has joined this group of related taxa. In their 2001 monograph, "Nepenthaceae
Nepenthaceae (2001 monograph)
"Nepenthaceae" is a monograph by Martin Cheek and Matthew Jebb on the tropical pitcher plants of Malesia, which encompasses Brunei, Indonesia, Malaysia, Papua New Guinea, the Philippines, and Singapore. It was published in 2001 by the National Herbarium of the Netherlands as the fifteenth volume of...
", 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,...
and 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....
also suggested a close relative in the 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...
n species N. adnata
Nepenthes adnata
Nepenthes adnata is a tropical pitcher plant endemic to the Indonesian province of West Sumatra, where it grows at elevations of 600 to 1200 m above sea level. The specific epithet adnata is Latin for "broadly attached" and refers to the base of the lamina.-Botanical history:Nepenthes adnata was...
.
Nepenthes hamata is very closely allied to N. tentaculata. It shares with this species the multicellular filiform appendages of the upper lid, as well as the general form of its laminae and pitchers. Nepenthes hamata clearly differs from N. tentaculata in the development of its peristome, which bears exaggerated flange-like extensions; N. tentaculata lacks conspicuous teeth altogether.
In their 2001 monograph, 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,...
and 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....
wrote that although the available herbarium material of N. hamata (around seven collections at the time) showed wide variation in peristome development, with some specimens appearing "very close to N. tentaculata", this did not represent a continuum of intergrades between N. hamata at one extreme and N. tentaculata at the other, but rather was due to a combination of lower and upper pitchers (the latter having more highly developed peristome teeth).
External links
- Photographs of N. hamata at the Carnivorous Plant Photofinder