''Nepenthes talangensis'' is a tropical

pitcher plant Pitcher plants are several different carnivorous plants which have modified leaves known as pitfall traps—a prey-trapping mechanism featuring a deep cavity filled with digestive liquid. The traps of what are considered to be "true" pitcher p ...

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

Sumatra Sumatra is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...

, where it grows in upper

montane forest Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. This stratification is a crucial f ...

at elevations of 1800–2500 m

above sea level Height above mean sea level is a measure of the vertical distance (height, elevation or altitude) of a location in reference to a historic mean sea level taken as a vertical datum. In geodesy, it is formalized as ''orthometric heights''. The comb ...

. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''talangensis'' is derived from the name of

Mount Talang Mount Talang ( id, Gunung Talang) () is an active stratovolcano in West Sumatra, Indonesia. Talang has two crater lakes on its flanks, the largest of which is wide and is called ''Lake Talang''. According to the Smithsonian Institution Global ...

, to which it is endemic, and the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

ending '' -ensis'', meaning "from".

Botanical history

Early specimens

Although only recognised as a distinct species towards the end of the 20th century, ''N. talangensis'' was collected as early as 1918 by

H. A. B. Bünnemeijer H is the eighth letter of the Latin alphabet. H may also refer to: Musical symbols * H number, Harry Halbreich reference mechanism for music by Honegger and Martinů * H, B (musical note) * H, B major People * H. (noble) (died after 1279 ...

.Clarke, C.M. 2001. ''

Nepenthes of Sumatra and Peninsular Malaysia ''Nepenthes of Sumatra and Peninsular Malaysia'' is a monograph by Charles Clarke on the tropical pitcher plants of Sumatra, Peninsular Malaysia, and their minor surrounding islands. It was published in 2001 by Natural History Publications (Borneo ...

''. Natural History Publications (Borneo), Kota Kinabalu. Bünnemeijer made three collections from

during this time. The specimen series ''Bünnemeijer 5398'' was collected on November 2, 1918, at an elevation of 2200 m. It is deposited at both Herbarium Bogoriense (BO), the

herbarium A herbarium (plural: herbaria) is a collection of preserved plant specimens and associated data used for scientific study. The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ...

of the

Bogor Botanical Gardens The Bogor Botanical Gardens ( id, Kebun Raya Bogor) is a botanical garden located in Bogor, Indonesia, 60 km south of central Jakarta. It is currently operated by Indonesian Institute of Sciences (Indonesian: ''Lembaga Ilmu Pengetahuan Indo ...

, and the

National Herbarium of the Netherlands National may refer to: Common uses * Nation or country ** Nationality – a ''national'' is a person who is subject to a nation, regardless of whether the person has full rights as a citizen Places in the United States * National, Maryland, ce ...

(L) in

Leiden Leiden (; in English and archaic Dutch also Leyden) is a city and municipality in the province of South Holland, Netherlands. The municipality of Leiden has a population of 119,713, but the city forms one densely connected agglomeration wit ...

(formerly Herbarium Lugduno-Batavum, the State Herbarium at Leiden), with all specimens lacking floral material. Bünnemeijer also collected ''Bünnemeijer 5397'' on the same day at an elevation of 2400 m. It is deposited at Herbarium Bogoriense and lacks floral material. Nepenthes bongso 1

Five days later, on November 7, ''Bünnemeijer 5521'' (or ''Bünnemeijer 2552'') was collected from 2500 m on Mount Talang. It is deposited at both Herbarium Bogoriense (male and female floral material) and the National Herbarium of the Netherlands (female floral material; sheet H.L.B. 822.60.920). Bünnemeijer made a fourth collection of ''N. talangensis'' from

Bukit Gombak Bukit Gombak is a subzone of Bukit Batok, Singapore. It is a hilly neighbourhood in the west-central area of the Southeast Asian city-state of Singapore. In the Malay language, ''bukit'' means hill and ''gombak'' a bunch or collection of somethi ...

on November 16, 1918, at an elevation of 2330 m. This specimen, designated as ''Bünnemeijer 5748 bis'' (or ''Bünnemeijer 6740''), is held at Herbarium Bogoriense and lacks floral material. It was collected on the same day as some of the earliest known specimens of '' N. inermis''.

Taxonomic confusion and formal description

''Nepenthes talangensis'' has been confused with '' N. bongso'' on a number of occasions. In his seminal 1928 monograph, "

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 and surrounding regions. It was originally published in the ''Bulletin du Jardin Botanique de Buitenzorg'' ...

B. H. Danser Benedictus Hubertus Danser (May 24, 1891, Schiedam – October 18, 1943, Groningen), often abbreviated B. H. Danser, was a Dutch taxonomist and botanist. Danser specialised in the plant families Loranthaceae, Nepenthaceae, and Polygonaceae. In 1928 ...

treated specimens of ''N. bongso'', '' N. ovata'', and ''N. talangensis'' all under ''N. bongso''.

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.Clarke, C.M. & C.C. Lee 2004. ''Pitcher Plants of Sarawak''. Natural History Publications (Borneo), ...

did the same in an article published in a 1973 issue of ''The Gardens' Bulletin Singapore''. Two early colour photographs of ''N. talangensis'' were published by Mike Hopkins, Ricky Maulder, and Bruce Salmon, in a 1990 issue of the ''

Carnivorous Plant Newsletter The ''Carnivorous Plant Newsletter'' is the official publication of the International Carnivorous Plant Society (ICPS), the largest such organization in the world. It is headquartered in Walnut Creek, California. History and editorship The newsle ...

'', where the species was again confused with, and identified as, ''N. bongso''.

Joachim Nerz Dr. Joachim Nerz (born 1964) is a German taxonomist and botanist specialising in the carnivorous plant genera ''Heliamphora'' and '' Nepenthes''. Nerz has described several new species, mostly with Andreas Wistuba. Publications * Schlauer, J. ...

conducted field studies of ''N. talangensis'' on

in 1986 and made three collections of the species: ''Nerz 2501'' consists of a short climbing stem with pitchers and floral material; ''Nerz 2502'' includes leaves and pitchers of the climbing stem and is preserved in

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

; and ''Nerz 2503'' comprises leaves and pitchers of the rosette. All three specimens were collected on September 6, 1986, from an elevation of 2200 m, and are deposited at the

(L) in

. Nerz's field studies, coupled with observations of ''N. bongso'' made by Mr. and Mrs. DeWitte on

Mount Singgalang Mount Singgalang (Gunung Singgalang in Indonesian) is a volcano in West Sumatra, Indonesia, about 10 km to the southwest of the town of Bukittinggi. Its elevation is 2,877 m (9,439 ft). It is a twin volcano with Mount Tandikat, which is ...

in 1993, showed that the two

taxa In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

almost certainly represented distinct species. To confirm this and prepare a formal description, Nerz and

Andreas Wistuba Andreas Wistuba (born 4 March 1967) is a German taxonomist and botanist specialising in the carnivorous plant genera ''Heliamphora'' and '' Nepenthes''. More than half of all known ''Heliamphora'' species have been described by Wistuba. Pub ...

examined herbarium specimens of both taxa, including ''Bünnemeijer 5398'', ''5521'', and ''5748 bis'', as well as material of ''N. bongso'' from

Mount Merapi Mount Merapi, ''Gunung Merapi'' (literally Fire Mountain in Indonesian and Javanese), is an active stratovolcano located on the border between the province of Central Java and the Special Region of Yogyakarta, Indonesia. It is the most active ...

(''Korthals s.n.'', the type specimen) and

(''Beccari 268''). This research culminated in the formal description of ''N. talangensis'' by Nerz and Wistuba in the December 1994 issue of the ''

''.Schlauer, J. N.d
''Nepenthes talangensis''
Carnivorous Plant Database. The authors designated ''Nerz 2501'' as the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

Matthew Jebb Matthew Hilary Peter Jebb (born 1958) is an Irish botanist and taxonomist specialising in the ant plant genera ''Squamellaria'', ''Myrmecodia'', ''Hydnophytum'', ''Myrmephytum'' and ''Anthorrhiza'', as well as the carnivorous plant genus ''Nepe ...

and

Martin Cheek Martin Roy Cheek (born 1960) is a botanist and taxonomist at the Royal Botanic Gardens, Kew.A skeletal revision of ''Nepenthes'' (Nepenthaceae)". The authors retained ''N. talangensis'' as a probable synonym of ''N. bongso'' in their 2001 revision, "

Nepenthaceae ''Nepenthes'' () is a genus of carnivorous plants, also known as tropical pitcher plants, or monkey cups, in the monotypic family Nepenthaceae. The genus includes about 170 species, and numerous natural and many cultivated hybrids. They are mos ...

", writing:

Each mountain peak in C Sumatra appears to support a slight variant of ''N. bongso'', and we have adopted a rather broad definition of the species. Specimens from Mt Talang have been distinguished as ''N. talangensis'', which may well merit recognition on the basis of photographs we have seen. However, we have not yet viewed the type specimens and for the meantime are leaving it as a synonym of ''N. bongso''.

Nerz and Wistuba disagreed with this synonymisation.

Charles Clarke Charles Rodway Clarke (born 21 September 1950) is a British Labour Party politician, who was the Member of Parliament (MP) for Norwich South from 1997 until 2010, and served as Home Secretary from December 2004 until May 2006. Early life Th ...

elevated ''N. talangensis'' to a species once again in his 2001 book, ''

''. The next detailed treatment of ''N. talangensis'' appeared in Stewart McPherson's 2009 monograph, ''

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 and covers all species kno ...

'', which retained it as a separate species. Despite the taxonomic confusion that has surrounded ''N. bongso'' and ''N. talangensis'', these two species are easily distinguished by their pitchers, which are quite dissimilar.

Discovery of tetraploids

The discovery of a new population of apparently

tetraploid Polyploidy is a condition in which the cells of an organism have more than one pair of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two sets of chromosomes, where each set contains ...

''N. talangensis'' was reported by Kazuhisa Mio in the July 2006 issue of the ''

Journal of Insectivorous Plant Society is a quarterly Japanese-language periodical and the official publication of the Insectivorous Plant Society of Japan.Rice, B. 2010Carnivorous Plant Society Archives The Carnivorous Plant FAQ. rchived page from October 10, 2010/ref> The journal ...

''. Mio, K. 2006
''Nepenthes talangensis'' の新自生地と4倍体と思われる個体
''

'' 57(3): 57.

Use in research

''Nepenthes talangensis'' was used in a 2009 study on the effect of prey capture on

photosynthetic efficiency The photosynthetic efficiency is the fraction of light energy converted into chemical energy during photosynthesis in green plants and algae. Photosynthesis can be described by the simplified chemical reaction :6 H2O + 6 CO2 + energy → C6H12O6 + ...

, published in the journal ''

Annals of Botany ''Annals of Botany'' is a monthly peer-reviewed scientific journal publishing experimental, theoretical and applied papers on all aspects of plant biology. The current (2022) Chief Editor is Rowan Sage, replacing John Seymour (Pat) Heslop-Harrison ...

''. The following year, the same authors published a study on the effect of

fertilisation Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Proce ...

on photosynthetic efficiency in prey-deprived ''N. talangensis''.

Description

''Nepenthes talangensis'' is a climbing plant growing to a height of 3 m. The

stem Stem or STEM may refer to: Plant structures * Plant stem, a plant's aboveground axis, made of vascular tissue, off which leaves and flowers hang * Stipe (botany), a stalk to support some other structure * Stipe (mycology), the stem of a mushro ...

is up to 0.5 cm in diameter and has internodes up to 10 cm long that are cylindrical-angular in cross section. The stem may be branched and is yellowish-green in colour. Leaves are

coriaceous This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

and

sessile Sessility, or sessile, may refer to: * Sessility (motility), organisms which are not able to move about * Sessility (botany), flowers or leaves that grow directly from the stem or peduncle of a plant * Sessility (medicine), tumors and polyps that ...

. The

lamina Lamina may refer to: Science and technology * Planar lamina, a two-dimensional planar closed surface with mass and density, in mathematics * Laminar flow, (or streamline flow) occurs when a fluid flows in parallel layers, with no disruption betwee ...

(leaf blade) varies in shape and may be linear,

lanceolate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

, or slightly

spathulate This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

. It measures up to 16 cm in length by 3 cm in width. The lamina has an acute or obtuse apex and an

attenuate In physics, attenuation (in some contexts, extinction) is the gradual loss of flux intensity through a medium. For instance, dark glasses attenuate sunlight, lead attenuates X-rays, and water and air attenuate both light and sound at variable a ...

base that clasps the stem. Two to three longitudinal veins are present on either side of the

midrib This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

Pinnate Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and in ...

veins are irregularly

reticulate Reticulation is a net-like pattern, arrangement, or structure. Reticulation or Reticulated may refer to: * Reticulation (single-access key), a structure of an identification tree, where there are several possible routes to a correct identificatio ...

Tendril In botany, a tendril is a specialized stem, leaf or petiole with a threadlike shape used by climbing plants for support and attachment, as well as cellular invasion by parasitic plants such as ''Cuscuta''. There are many plants that have tendr ...

s are up to 30 cm long. The lamina is dark green throughout, whereas the

and tendril are yellowish-green like the stem. Rosette and lower pitchers are only produced briefly before the plant starts to climb. They are either entirely

ovate Ovate may refer to: *Ovate (egg-shaped) leaves, tepals, or other botanical parts *Ovate, a type of prehistoric stone hand axe *Ovates, one of three ranks of membership in the Welsh Gorsedd *Vates In modern English, the nouns vates () and ovat ...

or only ovate in the upper half and

infundibular An infundibulum (Latin for ''funnel''; plural, ''infundibula'') is a funnel-shaped cavity or organ. Anatomy * Brain: the pituitary stalk, also known as the ''infundibulum'' and ''infundibular stalk'', is the connection between the hypothalamus and ...

below. They often narrow just below the peristome. Terrestrial pitchers grow to 10 cm in height by 6 cm in width. A pair of fringed wings (≤10 mm wide) usually runs down the

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...

surface of the trap, bearing filaments up to 8 mm long, although these wings may be absent altogether or only extend for a portion of the trap's length. The pitcher mouth is round and positioned horizontally in the front two-thirds, rising at the rear to form a short neck. The

peristome Peristome (from the Greek ''peri'', meaning 'around' or 'about', and ''stoma'', 'mouth') is an anatomical feature that surrounds an opening to an organ or structure. Some plants, fungi, and shelled gastropods have peristomes. In mosses In mosses, ...

is flattened, strongly incurved, and measures up to 15 mm in width. It bears ribs up to 0.8 mm high and spaced up to 1 mm apart. These ribs terminate in distinct teeth (≤3 mm long) on the inner margin of the peristome. The inner portion of the peristome accounts for around 78% of its total cross-sectional surface length.Bauer, U., C.J. Clemente, T. Renner & W. Federle 2012. Form follows function: morphological diversification and alternative trapping strategies in carnivorous ''Nepenthes'' pitcher plants. ''Journal of Evolutionary Biology'' 25(1): 90–102. The peristome forms a short neck at the rear, where the teeth form two parallel rows. The inner surface is wholly glandular; there is no waxy zone. The pitcher lid or operculum is ovate to elliptic and has a

cordate Cordate is an adjective meaning 'heart-shaped' and is most typically used for: * Cordate (leaf shape), in plants * Cordate axe, a prehistoric stone tool See also * Chordate A chordate () is an animal of the phylum Chordata (). All chordat ...

base. It measures up to 6 cm in length by 5 cm in width. It bears no appendages on its lower surface. A flattened

spur A spur is a metal tool designed to be worn in pairs on the heels of riding boots for the purpose of directing a horse or other animal to move forward or laterally while riding. It is usually used to refine the riding aids (commands) and to back ...

measuring up to 5 mm in length is inserted near the base of the lid. It may or may not be branched. Lower pitchers are typically light yellow to olive green and speckled with red or purple. The inner surface is a light shade of yellow. The peristome is generally yellow or orange in freshly opened traps, later becoming dark red to purple as the pitcher matures. The upper surface of the lid is often yellow with orange to purple blotches, whereas the underside may be completely red, although this is not always the case. Upper pitchers are either narrowly infundibular in the basal half of the pitcher cup and swollen above or infundibular throughout. A constriction is present just below the peristome. Aerial traps reach 12 cm in height by 6 cm in width. In upper pitchers, the wings may be partially developed near the pitcher mouth, or they may be reduced to ribs. The peristome reaches up to 24 mm in width and is similarly incurved to that found in terrestrial traps. Other parts of upper pitchers are similar to their lower counterparts. Upper pitchers exhibit a similar pigmentation to lower pitchers, but are typically lighter. ''Nepenthes talangensis'' has a

racemose A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

up to 14 cm long, of which the peduncle constitutes up to 5 cm and the

rachis In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this c ...

up to 9 cm. The peduncle has a basal diameter of 2 mm. Flowers are borne solitarily on

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...

(≤10 mm long) with simple

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 usually different from foliage leaves. They may be smaller, larger, or of ...

Tepal A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...

s are elliptic and up to 4 mm long. Female and male inflorescences have a similar structure. A sparse but persistent

indumentum In biology, an indumentum (Latin, literally: "garment") is a covering of trichomes (fine "hairs") on a plant Davis, Peter Hadland and Heywood, Vernon Hilton (1963) ''Principles of angiosperm taxonomy'' Van Nostrandpage, Princeton, New Jersey, pa ...

of simple, white hairs is present on most parts of the plant. The density of hairs on the pitchers may be so low that they appear

glabrous Glabrousness (from the Latin ''glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part of ...

. The laminar margins are lined with red, brown or white hairs measuring up to 3 mm. ''Nepenthes talangensis'' varies little across its restricted range and has no

infraspecific taxa In botany, an infraspecific name is the scientific name for any taxon below the rank of species, i.e. an infraspecific taxon or infraspecies. (A "taxon", plural "taxa", is a group of organisms to be given a particular name.) The scientific names ...

Ecology

''Nepenthes talangensis'' is thought to be

to the area around

in the

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

province A province is almost always an administrative division within a country or sovereign state, state. The term derives from the ancient Roman ''Roman province, provincia'', which was the major territorial and administrative unit of the Roman Empire ...

West Sumatra West Sumatra ( id, Sumatra Barat) is a Provinces of Indonesia, province of Indonesia. It is located on the west coast of the island of Sumatra and includes the Mentawai Islands off that coast. The province has an area of , with a population of 5, ...

; it has been recorded from Mount Talang itself and from nearby

. A population of apparently

plants is known. Although Nerz and Wistuba wrote in their formal description that ''N. talangensis'' is restricted to elevations above 2200 m, the species is now known to have a wider altitudinal distribution of 1800–2500 m.McPherson, S.R. & A. Robinson 2012. ''

Field Guide to the Pitcher Plants of Sumatra and Java This list of ''Nepenthes'' literature is a listing of major published works dealing with the tropical pitcher plants of the genus ''Nepenthes''. It includes specialised standalone publications and taxonomic monographs released as part of larger ...

''. Redfern Natural History Productions, Poole. The typical habitat of ''N. talangensis'' is mossy upper

, where it is almost exclusively terrestrial, but rarely may also be found as an

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

. It may grow in shady conditions under dense tree cover or among open, stunted shrubs where it is exposed to strong or even direct sunlight. At lower elevations of as little as 1800 m, ''N. talangensis'' is found in dense mossy forest, where it is sympatric with '' N. gymnamphora'' and '' N. inermis''. ''Nepenthes talangensis'' is seldom sympatric with '' N. bongso'', despite the latter being common on Mount Talang. This is because the two species occupy distinct

ecological niche In ecology, a niche is the match of a species to a specific environmental condition. Three variants of ecological niche are described by It describes how an organism or population responds to the distribution of resources and competitors (for ...

s; ''N. bongso'' is typically an epiphyte in lower montane forest, whereas ''N. talangensis'' usually grows terrestrially in upper montane forest.

Natural hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...

s with all three sympatric ''Nepenthes'' species have been recorded. The

conservation status The conservation status of a group of organisms (for instance, a species) indicates whether the group still exists and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation ...

of ''N. talangensis'' is listed as

Endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

on the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

, based on an assessment carried out in 2000. This agrees with an informal assessment made by

in 2001, who also classified the species as Endangered based on the

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

criteria. Since the species appears to be restricted to a single mountain, it would normally fall under the category of Critically Endangered. Stewart McPherson considered the species "not seriously threatened" in his 2009 monograph, describing extant wild populations as "extensive". A substantial number of plants persist on Mount Talang despite its recent

volcanic activity Volcanism, vulcanism or volcanicity is the phenomenon of eruption of molten rock (magma) onto the surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics, and volcanic gases erupt through a break in the surface called a ...

, which has included large

eruptions Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often ...

. Due to its status as an active volcano, Mount Talang receives few visitors and is not a major target for development.

Carnivory

''Nepenthes talangensis'' produces extremely thick,

mucilaginous Mucilage is a thick, gluey substance produced by nearly all plants and some microorganisms. These microorganisms include protists which use it for their locomotion. The direction of their movement is always opposite to that of the secretion of m ...

pitcher liquid, which coats the entire inner surfaces of the traps in a thin film. The pitchers of this species appear to function at least in part as flypaper traps, with the sticky inner walls trapping flying insects above the surface of the fluid. Similarly viscous pitcher fluid is also found in seven other closely allied

n species: '' N. aristolochioides'', '' N. dubia'', '' N. flava'', '' N. inermis'', '' N. jacquelineae'', '' N. jamban'', and '' N. tenuis''. Together with ''N. talangensis'', these species all share

pitchers that are wholly glandular or almost so.

Related species

Despite being confused with '' N. bongso'' throughout much of its botanical history, ''N. talangensis'' is clearly distinct from this species and can easily be distinguished on the basis of its greatly incurved peristome and smaller laminae with hair-fringed margins. In addition, the lower pitchers of ''N. bongso'' have a cylindrical upper portion that is non-glandular, whereas the lower traps of ''N. talangensis'' lack this cylindrical section and are wholly glandular. Furthermore, the laminar apex is acute to obtuse in ''N. talangensis'' and has a simple tendril insertion; ''N. bongso'' has a rounded apex, typically with a sub-apical tendril insertion. The funnel-shaped upper pitchers of ''N. talangensis'' may also be reminiscent of species such as '' N. eymae'', '' N. flava'', '' N. inermis'', '' N. pitopangii'', and '' N. tenuis''. However, ''N. talangensis'' differs from all of these in its combination of a wide lid without appendages and a greatly incurved peristome bearing conspicuous ribs and teeth. The pitchers of ''N. talangensis'' may also resemble those of '' N. jamban'', but are not as broad around the mouth and have a much wider lid. ''

Nepenthes aristolochioides ''Nepenthes aristolochioides'' is a tropical pitcher plant endemic to Sumatra, where it grows at elevations of 1800–2500 m above sea level. It has an extremely unusual pitcher morphology, having an almost vertical opening to its traps.McP ...

'' is thought to be the closest relative of ''N. talangensis'' and these two species share a very similar lamina structure. However, they are easily separated by their pitchers; those of ''N. aristolochioides'' are uniquely dome-shaped and have an almost vertical pitcher opening. In their formal description of ''N. talangensis'', Nerz and Wistuba compared it with '' N. bongso'', '' N. dubia'', and '' N. tenuis''. The authors distinguished it from these species on the basis of the shape of the upper pitchers, the lid, and the length/width ratio of the upper pitchers. The ratio was given as 2.3 for ''N.talangensis''; greater than that of ''N. tenuis'' (1.75) and ''N. dubia'' (1.9), but much lower than that of ''N. bongso'' (3.3).

Natural hybrids

Three

natural hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...

s involving ''N. talangensis'' have been recorded: with '' N. bongso'', '' N. gymnamphora'', and '' N. inermis''.McPherson, S.R. 2009. ''

''. 2 volumes. Redfern Natural History Productions, Poole.

''Nepenthes × pyriformis''

Nepenthes inermis ''Nepenthes inermis'' is a tropical pitcher plant endemic to the Indonesian island of Sumatra. The specific epithet ''inermis'' is Latin for "unarmed" and refers to the upper pitchers of this species, which are unique in that they completely la ...

'' is known to hybridise with ''N. talangensis'' on the upper slopes of

, where the two species grow sympatrically. Since ''N. talangensis'' was only described as a distinct species in 1994, some of the older literature identifies this hybrid as ''N. bongso'' × ''N. inermis''. This natural hybrid is similar to '' N. dubia'', but can be distinguished on the basis of several stable characters. The hybrid has a wider pitcher lid that is never relfexed beyond 90 degrees and the pitcher cup is not appressed in the lower parts as in ''N. dubia''. In addition, the mouth of ''N. inermis'' × ''N. talangensis'' is raised towards the back as opposed to being horizontal. ''Nepenthes inermis'' × ''N. talangensis'' has been the subject of taxonomic confusion in the past. In a 1973 article on the ''Nepenthes'' of Borneo, Singapore, and Sumatra,

incorrectly identified specimens of this hybrid as belonging to ''N. dubia''. In 1997,

and

Martin Cheek Martin Roy Cheek (born 1960) is a botanist and taxonomist at the Royal Botanic Gardens, Kew.A skeletal revision of ''Nepenthes'' (Nepenthaceae)", in which they referred to ''N. dubia'' plant material from

(''Kurata s.n.'' SING).

later identified ''Kurata s.n.'' as representing ''N. inermis'' × ''N. talangensis''. In 2001, Kurata described this hybrid as a new species, ''N. pyriformis''. Kurata, S. 2001. スマトラ島およびミンダナオ島産ウツボカズラの２新種(英文). wo new species of ''Nepenthes'' from Sumatra (Indonesia) and Mindanao (Philippines).''

'' 52(2): 30–34. Clarke rejected this interpretation in his monograph, ''

'', published the same year. Clarke found that the

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

of ''N. pyriformis'', ''Kurata & Mikil 4230'' NDC, matches the appearance of ''N. inermis'' × ''N. talangensis'' "in most respects".

References

External links

{{Taxonbar, from=Q4247238 Carnivorous plants of Asia talangensis Endemic flora of Sumatra Plants described in 1994 Endangered plants