View source for Nepenthes hamata

{{short description|Species of pitcher plant from Indonesia}}
{{Speciesbox
|image = Nepenthes hamata10.jpg
|image_caption = A lower pitcher of ''Nepenthes hamata'' from [[Mount Katopasa]], [[Sulawesi]]
|status = LC
|status_system = IUCN3.1
|status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Clarke, C.M. |date=2018 |title=''Nepenthes hamata'' |volume=2018 |page=e.T40111A143967359 |doi=10.2305/IUCN.UK.2018-1.RLTS.T40111A143967359.en |access-date=19 November 2021}}</ref>
|genus = Nepenthes
|species = hamata
|authority = [[John R. Turnbull|J.R.Turnbull]] & [[Anne T. Middleton|A.T.Middleton]] (1984)<ref name=hamata>Turnbull, J.R. & A.T. Middleton 1984. Three new ''Nepenthes'' from Sulawesi Tengah. ''Reinwardtia'' '''10'''(2): 107–111.</ref>
|synonyms = *''Nepenthes dentata''<br><small>[[Shigeo Kurata|Sh.Kurata]] (1984)<ref name=dentata>Kurata, S. 1984. {{cite web|url= http://www.sbg.org.sg/Bulletin/67_569.pdf |title=A new species of ''Nepenthes'' from Sulawesi, Indonesia. }} ''The Gardens' Bulletin Singapore'' '''36'''(2): 197–200.</ref><br>[=''N. hamata/[[Nepenthes nigra|N. nigra]]'']<ref name=McPherson>McPherson, S.R. 2009. ''[[Pitcher Plants of the Old World]]''. 2 volumes. Redfern Natural History Productions, Poole.</ref><ref name=nigra>Nerz, J., A. Wistuba, C.C. Lee, G. Bourke, U. Zimmermann & S. McPherson  2011. ''Nepenthes nigra'', a new pitcher plant from Central Sulawesi. In: McPherson, S.R. ''[[New Nepenthes: Volume One]]''. Redfern Natural History Productions, Poole. pp. 468–491.</ref></small>
*''Nepenthes hamata''<br><small>''auct. non'' [[John R. Turnbull|J.R.Turnbull]] & [[Anne T. Middleton|A.T.Middleton]]: [[Stewart McPherson (geographer)|S.McPherson]] (2009);<ref name=McPherson /> [[Stewart McPherson (geographer)|S.McPherson]] & [[Alastair Robinson|A.S.Rob.]] (2012)<ref name=McPhersonRobinson2012>McPherson, S.R. & A.S. Robinson 2012. ''[[Field Guide to the Pitcher Plants of Sulawesi]]''. Redfern Natural History Productions, Poole.</ref> [<nowiki>=</nowiki>''[[Nepenthes diabolica|N.&nbsp;diabolica]]''/''N.&nbsp;hamata'']</small>
*''Nepenthes hamatus''<br><small>[[John R. Turnbull|J.R.Turnbull]] & [[Anne T. Middleton|A.T.Middleton]] (1984)<ref name=hamata /></small><br><small>[original spelling]</small>
|}}

'''''Nepenthes hamata''''' {{IPAc-en|n|ᵻ|ˈ|p|ɛ|n|θ|iː|z|_|h|ə|ˈ|m|ɑː|t|ə}} is a tropical [[pitcher plant]] [[endemism|endemic]] to [[Sulawesi]], where it grows at elevations of 1,400–2,500&nbsp;m [[above sea level]].<ref name=McPherson />

The [[specific name (botany)|specific epithet]] ''hamata'' is derived from the [[Latin]] word ''[[wikt:hamatus|hamatus]]'', meaning "hooked". It describes the appearance of the highly developed [[peristome]] teeth of this species.<ref name=McPherson />

==Botanical history==

===Early history and formal descriptions===
''Nepenthes hamata'' was first encountered by [[Western world|Western]] explorers many decades before its formal description and recognition by science. [[Netherlands|Dutch]] botanist [[Pierre Joseph Eyma]] collected [[herbarium]] material of this species as early as 1938; this would later be used to [[#Type material|designate a type specimen]].<ref name=dentata /><ref name=C&J />

In 1984, two [[Species description|formal descriptions]] of this species were published in close succession: [[Shigeo Kurata]] described it under the name ''N.&nbsp;dentata'' in ''[[The Gardens' Bulletin Singapore]]'',<ref name=dentata /> while John R. Turnbull and Anne T. Middleton called it ''N.&nbsp;hamatus'' in the journal ''[[Reinwardtia (journal)|Reinwardtia]]''.<ref name=hamata />

As explained in the introduction to his describing paper on ''N.&nbsp;dentata'', Kurata first became aware of the species more than a decade earlier, on a 1972 visit to [[Herbarium Bogoriense]]:<ref name=dentata />

{{Quotation|During my stay at the Herbarium Bogoriense in 1972, for the study of their ''Nepenthes'' collection, I was able to examine much undetermined material from several Indonesian islands. While going through those collected by P. J. Eyma in Sulawesi, I came across a very interesting ''Nepenthes''. After subsequent study, I am now able to conclude that it should be described as a new species.}}

The name ''N.&nbsp;dentata'' was first published in Kurata's 1976 guide, ''[[Nepenthes of Mount Kinabalu]]'',<ref name=C&J /> where it was included in a table of all ''Nepenthes'' species known at the time and asterisked with the note "Not yet established".<ref>Kurata, S. 1976. ''[[Nepenthes of Mount Kinabalu]]''. Sabah National Parks Publications No. 2, Sabah National Parks Trustees, Kota Kinabalu.</ref>

===Questions over nomenclatural priority===
The formal descriptions of ''N.&nbsp;dentata'' by Kurata and ''N.&nbsp;hamatus'' by Turnbull and Middleton were published almost concurrently, leading to uncertainty over which name held [[Priority (nomenclature)|nomenclatural priority]]. A similar situation surrounded the publication of [[Nepenthes eymae|''N.&nbsp;eymae'' / ''N.&nbsp;infundibuliformis'']] and [[Nepenthes glabrata|''N.&nbsp;glabrata'' / ''N.&nbsp;rubromaculata'']], which were described by the same three authors.<ref name=C&J /><ref name=DAmato>D'Amato, P. 1993. {{cite web|url= http://www.carnivorousplants.org/cpn/articles/CPNv22n1_2p21.pdf |title=''Nepenthes eymai''. }} ''[[Carnivorous Plant Newsletter]]'' '''22'''(1–2): 21.</ref>

''Nepenthes hamata'' (emended with a feminine [[suffix]] to match the [[Grammatical gender|gender]] of ''Nepenthes'')<ref name=email>Schlauer, J. 1994. [http://www.omnisterra.com/botany/cp/list/cp94alld/2354.htm NEPENTHES comments for Flora Malesiana]. Carnivorous Plant Mailing List, September 9, 1994.</ref><ref name=IPNI>[http://ipni.org/ipni/idPlantNameSearch.do?id=904735-1 ''Nepenthes hamata'' J.R.Turnbull & A.T.Middleton]. [[International Plant Names Index]] (IPNI).</ref> gained greater currency and was said to have been published 21 days prior to ''N. dentata''.<ref name=Jebb>Jebb, M. 1994. [http://www.omnisterra.com/botany/cp/list/cp94alld/2353.htm NEPENTHES revision for Flora Malesiana]. Carnivorous Plant Mailing List, September 9, 1994.</ref> 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 [[International Code of Botanical Nomenclature|Botanical Code]]".<ref name=Jebb /> 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<ref>Kurata, S. 1984. New species of ''Nepenthes'' from Sulawesi, Indonesia. ''[[Journal of Insectivorous Plant Society]]'' '''35'''(2): 41–44.</ref> about the species in the ''[[Journal of Insectivorous Plant Society]]''.<ref name=email /> While some authors referred to the species as ''N.&nbsp;dentata'' in the following years,<ref name=Marabini1987>{{in lang|de}} Marabini, J. 1987. [https://www.biodiversitylibrary.org/page/15683425 Eine neue Unterart von ''Nepenthes edwardsiana'' Hook.fil. sowie Anmerkungen zur Taxonomie der Gattung ''Nepenthes'' L.]. ''Mitteilungen der Botanischen Staatssammlung München'' '''23''': 423–429.</ref> the name ''N.&nbsp;hamata'' enjoyed greater popularity and has for this reason been retained in all major monographs on the genus.<ref name=McPherson /><ref name=C&J>Cheek, M.R. & M.H.P. Jebb 2001. [[Nepenthaceae (2001 monograph)|Nepenthaceae]]. ''Flora Malesiana'' '''15''': 1–157.</ref><ref name=Jebb /><ref>Jebb, M.H.P. & M.R. Cheek 1997. [[A skeletal revision of Nepenthes (Nepenthaceae)|A skeletal revision of ''Nepenthes'' (Nepenthaceae)]]. ''Blumea'' '''42'''(1): 1–106.</ref>

In the years following its description, some authors considered the two [[taxon|taxa]] as separate species<ref>{{in lang|de}} Marabini, J. 1988. Zur taxonomischen Klassifizierung von ''Nepenthes dentata'' Kurata und ''Nepenthes hamatus'' Turnbull et Middleton. ''[[Das Taublatt]]'' '''9''': 4–7.</ref> and there was even speculation among growers that ''N.&nbsp;hamata'' represented a hybrid involving the "true" species, ''N.&nbsp;dentata''.<ref name=email /> Schlauer considers ''N.&nbsp;dentata'' to be a [[heterotypic synonym]] of ''N.&nbsp;hamata''.<ref name=db />

[[File:Nepenthes hamata hairy pitcher.jpg|thumb|left|A developing lower pitcher of ''[[Nepenthes diabolica|N.&nbsp;diabolica]]'' (once considered to be a hairy variant of ''N.&nbsp;hamata''), showing its shaggy, fur-like [[indumentum]]]]

===Type material===
The [[type specimen]] of ''N.&nbsp;hamata'' is ''J.R.Turnbull & A.T.Middleton 83121a'', which was collected from the west ridge of [[Mount Lumut]], [[Central Sulawesi]]<ref name=C&J /> (at the coordinates {{coord|1|07|S|121|39|E|scale:250000}}),<ref name=IPNI /> at an altitude of 1,850–1,900&nbsp;m, on September 19, 1983.<ref name=hamata /><ref name=C&J /><ref name=db>Schlauer, J. N.d. [http://www.omnisterra.com/bot/cp_home.cgi?name=Nepenthes+hamata ''Nepenthes hamata''] {{Webarchive|url=https://web.archive.org/web/20210423073134/http://www.omnisterra.com/bot/cp_home.cgi?name=Nepenthes+hamata |date=2021-04-23 }}. Carnivorous Plant Database.</ref> 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]].<ref name=hamata /> However, [[Martin Cheek]] and [[Matthew Jebb]] were unable to locate it there<ref name=C&J /> and, referring collectively to the type material of ''N.&nbsp;hamata'', ''[[Nepenthes glabrata|N.&nbsp;glabrata]]'', and ''[[Nepenthes infundibuliformis|N.&nbsp;infundibuliformis]]'' (which were all described by Turnbull and Middleton in the same paper),<ref name=hamata /> wrote that "[n]one of these collections has been found at the herbaria they cite".<ref name=C&J />

An early collection by [[Netherlands|Dutch]] botanist [[Pierre Joseph Eyma]], designated as ''Eyma 3572'', represents the type material of ''N.&nbsp;dentata''.<ref name=dentata /> The specimens of this series were taken from a site on the north spur of [[Mount Lumut]], between [[Bivouac shelter|bivouacs]] II and III, on September 3, 1938.<ref name=dentata /><ref name=C&J /> Both the [[lectotype]] and [[holotype|isotype]] are deposited at Herbarium Bogoriense (BO).<ref name=dentata /><ref name=C&J />

In addition to the herbarium specimens of ''N.&nbsp;hamata'' mentioned here, a number of others have appeared in the literature.{{Ref_label|A|note a|none}}

===Horticultural interest===
''Nepenthes hamata'' remained very rare in cultivation until around 1996.<ref name=Hansen>Hansen, E. 2001. [http://discovermagazine.com/2001/oct/featplants Where rocks sing, ants swim, and plants eat animals: finding members of the ''Nepenthes'' carnivorous plant family in Borneo]. ''Discover'' '''22'''(10): 60–68.</ref> Its scarcity and striking appearance made it particularly desirable to collectors, and individual plants commanded prices of approximately US$300–400 during this time.<ref name=Hansen /> The significant commercial value of the species encouraged wild collection by both local and foreign [[plant hunter]]s. Beginning in 1995,<ref name=Hansen /> [[Ch'ien Lee]] oversaw a ''Nepenthes'' [[Micropropagation|artificial propagation]] program at Malesiana Tropicals, a company based in [[Sarawak]], [[Malaysian Borneo]].<ref name=P&L2008>Phillipps, A., A. Lamb & C.C. Lee 2008. ''[[Pitcher Plants of Borneo]]''. Second Edition. Natural History Publications (Borneo), Kota Kinabalu.</ref> Seeds of ''N.&nbsp;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.<ref name=Hansen /> The increased supply led to a sharp fall in prices. The price of ''N.&nbsp;hamata'' was predicted in 2001 to stabilise at roughly $50 per plant, greatly limiting the incentive for wild collection.<ref name=Hansen /> The species however remains highly sought-after and is still somewhat of a horticultural rarity.<ref>Heng, S.B. 2013. [http://www.nst.com.my/nation/general/there-s-big-money-in-pitcher-plants-1.318487 There's big money in pitcher plants] {{Webarchive|url=https://web.archive.org/web/20130714175945/http://www.nst.com.my/nation/general/there-s-big-money-in-pitcher-plants-1.318487 |date=2013-07-14 }}. ''New Straits Times'', July 13, 2013.<!--https://www.webcitation.org/6I50hX7eo--></ref>

===Discovery of "red hairy ''hamata''"===

In early 2005, [[Ch'ien Lee]] announced the discovery of a new form of ''N.&nbsp;hamata'' with an exceptionally dense [[indumentum]]:<ref name=hairy>"Stairs" 2005. [http://www.cpukforum.com/forum/index.php?s=&showtopic=10122&view=findpost&p=85473 Re: New Hamata like species]. CPUK Forum, June 26, 2005. <!--https://www.webcitation.org/6K2v6fLsl--></ref>

{{Quotation|Thought people might be interested to see this stunning new variety of ''N.&nbsp;hamata'' which I recently photographed in Sulawesi. It comes from a mountain quite far away from the type locality of ''N.&nbsp;hamata'' and shows that this species has a good bit of geographical variation throughout its range.

Compared with the variety from Gunung Lumut (which is probably the source of all the plants currently in cultivation?), the pitchers of this new form are more robust and entirely red with a dense coating of rusty brown hairs. Also, the bristles on the lid are not as numerous nor branched. In all other vegetative respects it matches ''N.&nbsp;hamata'' very well.}}

In response to subsequent speculation about the plant's taxonomic status, Lee wrote that it "merely represents a geographical variant of ''N.&nbsp;hamata''".<ref name=hairy /> It was informally known as ''N.&nbsp;hamata'' "red hairy" or simply "red hairy ''hamata''" (often abbreviated as 'RHH').<ref name=diabolica /> In 2020, this taxon was described as a species in its own right: ''[[Nepenthes diabolica|N.&nbsp;diabolica]]''.<ref name=diabolica>Bianchi, A., C.C. Lee, M.R. Golos, F.S. Mey, M. Mansur, Y.M. Mambrasar & A.S. Robinson 2020. ''Nepenthes diabolica'' (Nepenthaceae), a new species of toothed pitcher plant from Central Sulawesi. ''Phytotaxa'' '''464'''(1): 29–48. {{doi|10.11646/phytotaxa.464.1.2}}</ref> Like the type form of ''N.&nbsp;hamata'', ''N.&nbsp;diabolica'' has been raised to flowering size in cultivation and used to make [[Hybrid (biology)|hybrid]]s with other ''Nepenthes'' species.<ref>[Anonymous] 2013. {{cite web|url= http://www.borneoexotics.com/newsletters/Borneo_Exotics_Newsletter_Vol_2_Issue_1.pdf |title=BE-3519 ''Nepenthes aristolochioides x hamata''. }} ''Nepenthes Growers Newsletter'' '''2'''(1): 3. <!--https://www.webcitation.org/6JddBkZpO--></ref>

===Later developments===
British geographer [[Stewart McPherson (geographer)|Stewart McPherson]] published an updated description of the species in his 2009 monograph, ''[[Pitcher Plants of the Old World]]''.<ref name=McPherson /> The book also covered the closely related [[undescribed taxon]] ''N.''&nbsp;sp.&nbsp;Sulawesi, which McPherson had observed with Greg Bourke in 2007.<ref name=McPherson /> ''Nepenthes'' sp. Sulawesi was described as ''[[Nepenthes nigra|N.&nbsp;nigra]]'' in McPherson's 2011 work, ''[[New Nepenthes]]''.<ref name=nigra />

==Description==

{{multiple image
 | align     = right
 | footer    = A young [[rosette (botany)|rosette]] plant growing among moss and detritus (left) and a slightly older specimen that has already begun scrambling along the ground (right), both from Mount Katopasa. 
 | width     = 260
 | image1    = Nepenthes hamata15.jpg
 | image2    = Nepenthes hamata3.jpg
}}
''Nepenthes hamata'' is a strong climber. The [[Plant stem|stem]], which may be branched, reaches a maximum length of around 7&nbsp;m.<ref name=McPherson /> It is [[wikt:terete|terete]] to obtusely [[wikt:trigonous|trigonous]] and varies in diameter from up to 3&nbsp;mm in [[rosette (botany)|rosettes]] and short stems, to 4–5&nbsp;mm in climbing stems. In the former, the [[Internode (botany)|internodal]] length is typically up to 6&nbsp;mm and in the latter 3.5–6&nbsp;cm.<ref name=C&J />

===Leaves===
Leaves are [[wikt:sessile|sessile]] and [[wikt:chartaceous|chartaceous]] in texture.<ref name=C&J /> The shape of the [[Leaf#Large-scale features (leaf morphology)|lamina]] (leaf blade) is variable: it may be linear, [[wikt:lanceolate|lanceolate]], or slightly elliptic.<ref name=McPherson />

In the case of rosettes and short stems, the lamina is typically [[wikt:oblanceolate|oblanceolate]] to oblong-elliptic and measures up to 7.5&nbsp;cm in length by 2.5&nbsp;cm in width. It has an acute apex and does not exhibit a [[wikt:peltate|peltate]] tendril attachment. The laminar base is [[wikt:amplexicaul|amplexicaul]], clasping the stem and giving it a [[wikt:perfoliate|subperfoliate]] appearance. [[Auricle (botany)|Auricles]] may be present, although their level of development varies. The lamina may be slightly [[wikt:decurrent|decurrent]] down the stem, but not prominently so.<ref name=C&J />

[[File:Nepenthes hamata12.jpg|thumb|260px|left|An offshoot from an old climbing stem bearing bright red laminae and disproportionately large rosette pitchers]]

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&nbsp;cm in length by 1.8<ref name=C&J />–4&nbsp;cm in width.<ref name=McPherson /> 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&nbsp;cm in some populations.<ref name=McPherson /><ref name=C&J /> 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. [[wikt:pinnate|Pinnate]] veins are inconspicuous; they are [[wikt:patent|patent]] and branching.<ref name=C&J />

===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&nbsp;cm high by 5&nbsp;wide. They are ovate in the basal fifth to half of the pitcher cup, being bulbous to varying degrees in this portion,<ref name=McPherson /> often narrowly so.<ref name=C&J /> The pitcher is narrower in the upper part and may be cylindrical or slightly [[wikt:infundibular|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&nbsp;mm wide runs down the ventral surface of the pitcher cup. These wings bear densely packed [[wikt:filiform|filiform]] fringe elements up to 19&nbsp;mm long, which commonly exceed the width of the wings themselves.<ref name=McPherson /> These filaments are often arranged in pairs, spaced around 2&nbsp;mm apart, and are usually branched [[wikt:dichotomous|dichotomously]] once or twice.<ref name=C&J /> The waxy zone of the inner surface is well developed.<ref name=Baueretal2012>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. {{doi|10.1111/j.1420-9101.2011.02406.x}}</ref>
{{multiple image
 | align     = right
 | footer    = Three lower pitchers, all produced by plants from Mount Katopasa, showing the variability in pigmentation exhibited by this species. The pitcher on the left has quite typical colouration, similar to that of plants from Mount Lumut. The reddish pitcher in the centre exhibits a conspicuous indumentum, widely spaced peristome ribs, and a noticeably inclined neck that overarches the pitcher mouth. The trap on the right has unusually dark pigmentation, with the dark blotches merging to form a solid purple surface. This specimen also displays golden highlights on the peristome ribs and a colourful waxy zone on the interior.
 | width     = 200
 | image1    = Nepenthes hamata7.jpg
 | image2    = Nepenthes hamata2.jpg
 | image3    = Nepenthes hamata22.jpg
}}
{{multiple image
 | align     = right
 | footer    = A trio of upper pitchers from Mount Katopasa. The pitcher on the left displays relatively small and numerous peristome teeth. The other two have distinctly rhomboid mouths with well-developed ribs, although they differ markedly in external mottling.
 | width     = 200
 | image1    = Nepenthes hamata5.jpg
 | image2    = Nepenthes hamata17.jpg
 | image3    = Nepenthes hamata upper pitcher.jpg
}}
The pitcher mouth is often distinctly rhomboid in shape, but may also be oval<ref name=McPherson /> 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,<ref name=C&J /> glossy, rigid, and up to 5&nbsp;mm wide (excluding the teeth). It consists of expanded ribs up to 6&nbsp;mm high and spaced up to 5&nbsp;mm apart. The entire flanges can measure up to 15&nbsp;mm in length, although their size and number differ between populations<ref name=McPherson /> (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 ([[wikt:falcate|falcate]]) and extend approximately 7&nbsp;mm into the interior, as measured from the inner edge of the peristome to the tooth apex. The outer edge of the peristome is [[wikt:entire|entire]], with the recurved flanges extending for around 2&nbsp;mm past the rim. The teeth of the neck may assume a dagger-like shape and measure up to 10&nbsp;mm by 2&nbsp;mm.<ref name=C&J /> These uppermost teeth are often noticeably splayed forward.<ref name=McPherson />

The pitcher lid or [[operculum (botany)|operculum]] is elliptic to ovate and measures up to 6&nbsp;cm in length by 5&nbsp;cm in width.<ref name=McPherson /> It is held roughly horizontally and often has upturned margins. The apex is rounded,<ref name=C&J /> whereas the base is occasionally [[wikt:cordate|cordate]]<ref name=McPherson /> or subcordate.<ref name=C&J /> 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&nbsp;mm long and may be branched.<ref name=McPherson /> 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&nbsp;mm in diameter.<ref name=C&J /> A [[spur (botany)|spur]] up to 9&nbsp;mm long is inserted near the base of the lid. It may be simple or repeatedly branched<ref name=McPherson /> to the point of being [[wikt:fasciculate|fasciculate]]. The herbarium material examined by Cheek and Jebb exhibited spurs that were basally 5-branched, with each branch being secondarily [[wikt:ramified|ramified]].<ref name=C&J />

Upper pitchers are similar in shape to their terrestrial counterparts, though usually more elongated, growing to 7<ref name=C&J />–25&nbsp;cm in height<ref name=McPherson /> by 1.2<ref name=C&J />–6&nbsp;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.<ref name=McPherson /> These teeth are usually 12–16&nbsp;mm long by 2–3&nbsp;mm high, and spaced 2.5–6&nbsp;mm apart.<ref name=C&J /> Upper pitchers resemble lower ones in most other respects.<ref name=McPherson />

===Inflorescence===
''Nepenthes hamata'' has a [[raceme|racemose]] [[inflorescence]].<ref name=McPherson /> The male inflorescence is 8–15&nbsp;cm long, of which the [[peduncle (botany)|peduncle]] constitutes 2.4–10&nbsp;cm<ref name=C&J /> and the [[rachis]] up to 8&nbsp;cm. The peduncle has a basal diameter of around 3&nbsp;mm.<ref name=McPherson /> Flowers are borne solitarily on [[wikt:ebracteate|ebracteate]] [[pedicel (botany)|pedicels]] measuring 10–15&nbsp;mm in length by 0.1–0.3&nbsp;mm in width. The pedicels number around 22 per inflorescence. [[Tepal]]s are elliptic, reflexed, and 1.5<ref name=C&J />–3&nbsp;mm long<ref name=McPherson /> by 1–1.5&nbsp;mm wide. [[Androphore]]s are 1–2.5&nbsp;mm long and bear [[anther]] heads measuring 0.6–0.8&nbsp;mm by 0.8–1.4&nbsp;mm. One [[infructescence]] was measured at 8.5&nbsp;cm long by roughly 5&nbsp;cm wide (fruits included), with a peduncle measuring 6.5&nbsp;cm in length and having a basal diameter of 2.25&nbsp;mm. [[Fruit]]s number around 15 per infructescence and bear valves 19–20&nbsp;mm long by 3.5–4.5&nbsp;mm wide. As in most ''Nepenthes'' species, the [[seed]]s are filiform. They are around 8&nbsp;mm long by 0.4–0.6&nbsp;mm wide.<ref name=C&J />

===Indumentum===
The extent of the [[indumentum]] is highly variable. Most populations are predominantly [[wikt:glabrous|glabrous]], having soft orange to brown hairs only on developing pitchers, tendrils, and the underside of the midrib.<ref name=McPherson />

<!--===Colouration===
"The red hairy plant in the photograph merely represents a geographical variant of N. hamata, and it does NOT occur at the type locality (sorry, not revealing any localities for now). The plants in this population appear to have very little variation, although peristome color is occasionally yellowish-green between the teeth. Upper pitchers of this variety are generally orange in color and although they do have a nicely toothed peristome, the claws are not as long as the G. Lumut variety."<ref name=hairy />-->
Despite the variation between populations, no [[infraspecific taxon|infraspecific taxa]] of ''N.&nbsp;hamata'' have been described.<ref name=McPherson />

{{multiple image
 | align     = left
 | footer    = An aerial rosette (left) and a lower pitcher embedded in moss (right), both from Mount Katopasa
 | width     = 200
 | image1    = Nepenthes hamata11.jpg
 | image2    = Nepenthes hamata8.jpg
}}

==Ecology and conservation==
''Nepenthes hamata'' is [[endemism|endemic]] to the [[Indonesia]]n island of [[Sulawesi]], where it has been recorded primarily from the eastern portion of [[Central Sulawesi]] [[Provinces of Indonesia|province]] (including large parts of the [[East Peninsula]]).<ref name=McPherson /> The species has a known altitudinal distribution of 1,400–2,500&nbsp;m [[above sea level]].<ref name=McPherson />

''Nepenthes hamata'' may grow terrestrially or as an [[epiphyte]]. It is found in lower and upper montane [[mossy forest]] and among [[Shrubland|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 hybrid]]s with ''[[Nepenthes glabrata|N.&nbsp;glabrata]]'' and ''[[Nepenthes tentaculata|N.&nbsp;tentaculata]]''.<ref name=McPherson /> The wild cross with ''N.&nbsp;glabrata'' was first reported by [[Ch'ien Lee]] in December 2006.<ref>Lee, C.C. 2006. [http://pitcherplants.proboards34.com/index.cgi?board=nepwild&action=display&thread=1165243618&page=1#1165243618 Sulawesi Photographs] {{webarchive|url=https://web.archive.org/web/20070927194320/http://pitcherplants.proboards34.com/index.cgi?board=nepwild&action=display&thread=1165243618&page=1 |date=2007-09-27 }}. Carnivorous Plants in the tropics, December 4, 2006.</ref>

The [[conservation status]] of ''N.&nbsp;hamata'' is listed as [[Least-concern species|Least concern]] on the [[IUCN Red List]], based on an assessment carried out in 2018.<ref name="iucn status 19 November 2021" /> In 2009, [[Stewart McPherson (geographer)|Stewart McPherson]] wrote that the species is "widespread" across its range and that most populations are "remote and not generally threatened at present".<ref name=McPherson /> ''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.<ref name=McPherson /> McPherson emphasised the need to monitor populations of specific variants, particularly the red hairy form (now known as ''[[Nepenthes diabolica|N.&nbsp;diabolica]]''), because "[l]oss of diversity [...] may become a legitimate concern in the future as a result of collection pressures".<ref name=McPherson />

<!--==Carnivory==-->

==Related species==
[[File:Nepenthes hamata4.jpg|thumb|260px|A closeup of a pair of ''N.&nbsp;hamata'' pitchers, showing the distinctive peristome structure that distinguishes this species from its closest relatives]]
''Nepenthes hamata'' belongs to what has been called the "Hamata group", which also includes four other closely related species from [[Borneo]] and [[Sulawesi]]: ''[[Nepenthes glabrata|N.&nbsp;glabrata]]'', ''[[Nepenthes muluensis|N.&nbsp;muluensis]]'', ''[[Nepenthes murudensis|N.&nbsp;murudensis]]'', and ''[[Nepenthes tentaculata|N.&nbsp;tentaculata]]''.<ref>Meimberg, H. & G. Heubl 2006. Introduction of a nuclear marker for phylogenetic analysis of Nepenthaceae. ''Plant Biology'' '''8'''(6): 831–840. {{doi|10.1055/s-2006-924676}}</ref> More recently, ''[[Nepenthes nigra|N.&nbsp;nigra]]'' has joined this group of related taxa.<ref name=nigra /> In their 2001 monograph, "[[Nepenthaceae (2001 monograph)|Nepenthaceae]]", [[Martin Cheek]] and [[Matthew Jebb]] also suggested a close relative in the [[Sumatra]]n species ''[[Nepenthes adnata|N.&nbsp;adnata]]''.<ref name=C&J />

''Nepenthes hamata'' is very closely allied to ''N.&nbsp;tentaculata''.<ref name=McPherson /><ref name=C&J /> 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.&nbsp;tentaculata'' in the development of its peristome, which bears exaggerated flange-like extensions; ''N.&nbsp;tentaculata'' lacks conspicuous teeth altogether.<ref name=McPherson /><ref name=C&J />

In their 2001 monograph, [[Martin Cheek]] and [[Matthew Jebb]] wrote that although the available herbarium material of ''N.&nbsp;hamata'' (around seven collections at the time) showed wide variation in peristome development, with some specimens appearing "very close to ''N.&nbsp;tentaculata''", this did not represent a continuum of intergrades between ''N.&nbsp;hamata'' at one extreme and ''N.&nbsp;tentaculata'' at the other, but rather was due to a combination of lower and upper pitchers (the latter having more highly developed peristome teeth).<ref name=C&J />

==Notes==
{{refbegin}}
:a.{{Note_label|A|a|none}}Other published specimens of ''N.&nbsp;hamata'' include ''Lack & Grimes 1783'' (includes an [[infructescence]] and female flowers) and ''Lack & Grimes 1784'' (includes a climbing stem with an upper pitcher and male inflorescence).<ref name=C&J /> Both of these specimens, along with ''Eyma 3573'', are illustrated in a line drawing by Camilla Speight in [[Martin Cheek]] and [[Matthew Jebb]]'s 2001 monograph, "[[Nepenthaceae (2001 monograph)|Nepenthaceae]]".<ref name=C&J /><p>A 2001 review of the ''Nepenthes'' material deposited at Herbarium Bogoriense found seven sheets of ''N.&nbsp;hamata'' within its collections.<ref name=herbarium>{{in lang|id}} Mansur, M. 2001. {{cite web |url= http://elib.pdii.lipi.go.id/katalog/index.php/searchkatalog/downloadDatabyId/1286/1286.pdf |title= Koleksi ''Nepenthes'' di Herbarium Bogoriense: prospeknya sebagai tanaman hias. |url-status= dead |archive-url= https://web.archive.org/web/20120319205635/http://elib.pdii.lipi.go.id/katalog/index.php/searchkatalog/downloadDatabyId/1286/1286.pdf |archive-date= 2012-03-19 }} In: ''Prosiding Seminar Hari Cinta Puspa dan Satwa Nasional''. Lembaga Ilmu Pengetahuan Indonesia, Bogor. pp.&nbsp;244–253.</ref> These specimens had been collected in [[montane forest]] at 1800–1900&nbsp;m.<ref name=herbarium /></p>
{{refend}}

==References==
{{Reflist|2}}

==Further reading==
{{Refbegin|2}}
* {{in lang|cs}} Flísek, J. 2003. [http://www.darwiniana.cz/sklad/sklad/Trifid/skeny/600DPI/T2003_1/35.png Věčně hladová kráska ''Nepenthes hamata'']. ''[[Trifid (journal)|Trifid]]'' '''2003'''(1): 35–37. ([http://www.darwiniana.cz/sklad/sklad/Trifid/skeny/600DPI/T2003_1/36.png page 2], [http://www.darwiniana.cz/sklad/sklad/Trifid/skeny/600DPI/T2003_1/37.png page 3])
* Meimberg, H., A. Wistuba, P. Dittrich & G. Heubl 2001. Molecular phylogeny of Nepenthaceae based on cladistic analysis of plastid trnK intron sequence data. ''Plant Biology'' '''3'''(2): 164–175. {{doi|10.1055/s-2001-12897}}
* {{in lang|de}} Meimberg, H. 2002. {{cite web|url= http://edoc.ub.uni-muenchen.de/1078/1/Meimberg_Harald.pdf |title=Molekular-systematische Untersuchungen an den Familien Nepenthaceae und Ancistrocladaceae sowie verwandter Taxa aus der Unterklasse Caryophyllidae s. l.. }} Ph.D. thesis, Ludwig Maximilian University of Munich, Munich.
* Meimberg, H., S. Thalhammer, A. Brachmann & G. Heubl 2006. Comparative analysis of a translocated copy of the ''trnK'' intron in carnivorous family Nepenthaceae. ''Molecular Phylogenetics and Evolution'' '''39'''(2): 478–490. {{doi|10.1016/j.ympev.2005.11.023}}
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{{Refend}}

==External links==
{{Commons|Nepenthes hamata}}
* [http://www.cpphotofinder.com/nepenthes-hamata-597.html Photographs of ''N.&nbsp;hamata''] at the Carnivorous Plant Photofinder

{{Nepenthes}}

{{Taxonbar|from=Q746088}}

[[Category:Carnivorous plants of Asia]]
[[Category:Nepenthes|hamata]]
[[Category:Endemic flora of Sulawesi]]
[[Category:Plants described in 1984]]