Reinstatement of Nepenthes hemsleyana (Nepenthaceae), an endemic pitcher plant from Borneo, with a discussion of associated Nepenthes taxa

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Blumea 58, 2013: 8–12 www.ingentaconnect.com/content/nhn/blumea http://dx.doi.org/10.3767/000651913X668465 RESEARCH ARTICLE InTRoduCTIon The Asian pitcher plant genus Nepenthes has seen a remarkableincreaseinspeciesnumberoverthelastfewdecades(Jebb &Cheek1997,Cheek&Jebb2001),andourunderstanding oftheirphysiologyandecologyhasgrownsubstantially.This is due to ongoing exploration of remote areas and historical collections,andthesteadilyrisingacademicinterest.Thespecieswepresentherewasfirstcollected136yearsago,buthas been considered a synonym of the more common N. rafflesiana Jackformostofthetimesince.However,overtheyears,many researchers have independently noted two rather different kinds ofplantgoingunderthatname.Wewilloutlinethebotanical history and current opinion on this long neglected Nepenthes species, which was strongly influenced by the consideration of onlyrecentlyestablishedecologicalcontext(seealsoClarke &Moran2011). ThefirstcollectionofthespecieswasmadebyFrederickBurbidge, the renowned Victorian plant hunter who travelled Borneo andtheSuluArchipelagoin1877–1878.Amongmanyother botanical gems, he introduced the giant pitcher plant N. rajah Hook.f.InSeptember1877,onhisfirstvisittoBorneo,heleft Labuan Island and sailed up the Lawas River (present-day northernSarawak,Malaysia;Burbidge1880).Hestayedin “Meringit, a Kadyan settlement at the head of the Meropok branch[oftheLawasRiver]”.Onanexcursion,heandhisparty “followed one little stream for about two miles, and reached a rockyhillaboutfivehundredfeethigh[…]”.Onthishillthey foundfivetypesofpitcherplant:N. gracilisKorth.,N. hirsuta Hook.f.,N. rafflesiana, N. veitchiiHook.f.,“andthelarge-urned variety of the last named, known as ‘glaberrima’”.Hereports the collection of an undetermined number of specimens from this site, but not from any other sites on his only Lawas trip (Burbridge1880).Unfortunately,Burbidgeassignednocollector numbers, and material from his Borneo voyage was later distributedtoKew(K),theBritishMuseumofNaturalHistory (BM),SaintPetersburg(LE),Bogor(BO),Singapore(SING) andEdinburgh(E)(VanSteenis-Kruseman&VanWelzen1950 onwards);weusestandardherbariumacronymsfollowingIndex Herbariorum(Thiers,continuallyupdated).Notethatthename N. rafflesiana “glaberrima”asusedbyBurbidgetorefertoa distinctkindofpitcherplantwasinformal.Nothingsuggestsa connection to N. rafflesianavar.glaberrimaHook.f.,whichwas describedpriortoBurbidge’svoyagebutlacksspecimensand mentionofpitchercharacteristics(Hooker1873). Threedecadeslater,Burbidge’sspecimensfromLawaswere investigatedmoreclosely.Basedon‘separateexamples’inK (identifiedhereasK000651484,K000651485,K000651486), andsingle examplesinBMandinHarvardeach,N. hemsleyanaMacfarl.wasdescribedasanewspecies(Macfarlane 1908).Unfortunately,nocorrespondingspecimensareregisteredtodayinthedatabasesofBM(http://www.nhm.ac.uk/ research-curation/collections/departmental-collections/botanycollections/search/index.php,lastaccessed12March2013) andA,whichnowincludesallvascularcollectionsatHarvard (http://kiki.huh.harvard.edu/databases/specimen_index.html, lastaccessed12March2013).InhiskeytoNepenthes, Macfarlane(1908:29)contrastsN. rafflesiana with N. hemsleyana asfollows(translatedfromLatin): “[B.a.β.III.]2.Pitcherssub-distended(subventricosa)totubulous, cylindrical comb-like peristome very elongated into a neck, edge comb-like, pitcher inside to the middle or below middle glabrous then glandulous ➝ N. hemsleyana. [B.a.β.III.]3.Pitchersdistended(ventricosa)tofunnel-shaped, the wide peristome skewed towards the inside, very elongated into a neck, edge comb-like, pitcher inside through the upper quarter or third part glabrous then glandulous ➝ N. rafflesiana.” Innotestoitsdescription,N. hemsleyana is portrayed as resembling N. rafflesiana “by the long leaf stalk and the elongated comb-likeperistome”,whilebeingdistinctin“thenervesofthe leaves, the long and slender tendril, the slim and elongated Reinstatement of Nepenthes hemsleyana (Nepenthaceae), an endemic pitcher plant from Borneo, with a discussion of associated Nepenthes taxa M.Scharmann1,T.U.Grafe2 Key words Borneo endemic Malesia Nepenthes pitcher plant reinstatement taxonomy 1 DepartmentofAnimalEcologyandTropicalBiology,UniversityofWürzburg, AmHubland,97074Würzburg,Germany;DepartmentofZoology,UniversityofCambridge,DowningStreet,CambridgeCB23EJ,UK;Instituteof IntegrativeBiology,ETHZurich,Universitätsstrasse16,CH-8092Zurich, Switzerland;  correspondingauthore-mail:[email protected]. 2 DepartmentofBiology,UniversitiBruneiDarussalam,TungkuLink,Gadong 1410,BruneiDarussalam. AbstractRecently,N. baramensis and N. rafflesiana var.subglandulosa were described from Borneo as new taxa closely related to N. rafflesiana.However,comparisonofnewcollectionsmadeinBorneowithN. baramensis and N. rafflesiana var.subglandulosaindicatedasynonymy.Furthermore,theywereidenticaltoN. hemsleyana, an older taxon formerly treated as synonym of N. rafflesiana.AcknowledgingthetaxonomicdifferencestoN. rafflesiana, the name N. hemsleyanaisreinstatedfollowingthepriorityrule.Newevidenceispresentedthatstrengthensthe interpretation to split N. rafflesiana and N. hemsleyana. Published on 8 May 2013 9 M.Scharmann&T.U.Grafe:ReinstatementofNepenthes hemsleyana pitchers, the heart-shaped lid with diffused glands, the deep (profunda)off-leading(deducente) surface” (translated from Latin,Macfarlane1908).Thelastcharacteristicisevenmore elaborate in the description of the upper pitchers as “inside throughupperhalfordeeperwaxy(glaucum),darkened(opacum)andleadingoff(deducens),belowshiny(nitidum)glandularanddetaining(detinens)”.ItappearsMacfarlanealready had a decent understanding of the different biomechanical propertiesofthesesurfaces. Just20yearslater,Danser(1928)reducedN. hemsleyana to a synonym of N. rafflesiana.Hewrote: “IntheseparationofN. hemsleyana IcannotfollowMacfarlane;Ihaveseenspecimensthatmoreorlessagreewiththe original description, especially Hallier B 1459[OeloeKenepai, 20.12.1893,locatedatBO],butIcanfindnoreasontoconsider themasadistinctspecies.” DanserdidnotincludeK,BMandHarvardinhislistofinstitutions he visited while researching his revision, and for his description of N. rafflesianaheonlysawonesheetfromBurbidge’s voyage,amalespecimen(s.n.)locatedatSING.Ittherefore appears that N. hemsleyana was reduced to synonymy without investigationofthetypematerial.Danserspecifiestheinner surface of upper pitchers of N. rafflesiana as wholly glandular, a characteristic clearly not exhibited by at least one of the type specimens of N. hemsleyana(K000651485). InthemostrecenttreatmentsofthegenusNepenthes,Danser’s interpretation of N. hemsleyana as belonging to N. rafflesiana wascontinued(Jebb&Cheek1997,Cheek&Jebb2001). But especially during the last decade, our knowledge of Nepenthes in Borneo has greatly improved.As highlighted by Clarkeetal.(2011),anumberofauthorshaveobservedor experimentally demonstrated stable ecological, physiological and morphological differences between two subgroups within the taxon N. rafflesiana sensuDanser,comprisingdifferentUV reflectancepatterns,scentproductionandcapturerate(Moran 1996),thedifferentontogenyofpitchermorphology(Gaume& DiGiusto2009),alternativeinsecttrappingstrategies(Bauer etal.2011),andamutualisticinteractionwithbatsexclusive foronesubgroup(Grafeetal.2011,Schöneretal.2013).Although the two subgroups were clearly understood by all of the specialists, the nomenclature used has been informal and inconsistent,untilClarkeetal.(2011)resolvedthisbyrecognising two separate species, splitting the new taxon N. baramensis C.Clarke,J.A.Moran&Chi.C.LeefromN. rafflesiana. Independentfromalloftheworkabove,N. rafflesiana var. subglandulosaJ.H.Adam&HafizawasdescribedfrommaterialcollectedinnorthernSarawak(Adam&Hamid2006).It differs from typical N. rafflesiana by the presence of a waxy layer on the inside of the upper pitchers, covering the upperfifthoftheirlength.Adam&Hamid(2006)reportanother collection belonging to this taxon from Brunei, which appears to be Jacobs 5684,thesheetofwhichatKew(K000651487)is labelled as an isotype and with “determinavit: N. rafflesiana var. subglandulosaAdametWilcock,J.H.Adam25.1.1991”.Note thatin1991thisnamewasnotyetvalidlypublished.Although N. rafflesiana var. subglandulosa resembles the informally named plants known from ecological research in Brunei and N. baramensis, a relationship between them was not established byanyauthor.SinceClarkeetal.(2011)includedaduplicate of Jacobs 5684atKuching,Sarawak(SAR)intheirdescription of N. baramensis, it is evident that both names had been given tothesameplant. Here,weshowthattheprimarymorphologicaldifferencebetween N. rafflesiana and N. hemsleyana, the presence or absenceofawaxyzoneinupperpitchers,islinkedwithcharacteristic shapes and proportions of leaves on climbing stems and rosettes.Thus,wearguethatMacfarlane(1908)wascorrect in treating N. hemsleyana as a distinct species, and that the taxa described byAdam & Hamid (2006) andClarkeetal. (2011)belongtothisspecies.Accordingly,N. baramensis and N. rafflesiana var.subglandulosa are recognised as heterotypic synonyms of N. hemsleyana, which is reinstated according to thepriorityrule. MATERIALS And METHodS Fieldwork to compare leaf proportions was conducted in six different sites in Brunei Darussalam, in the Tutong and Belait Districts.Sixty-fourplantsoftheN. hemsleyana–N. rafflesiana subgroup were assigned to four categories, which correspond to the combinations of two distinct characters with two states each.Thefirstcharacterwasstatusofthewaxyzoneinupper pitchers(eitherpresentorabsent),thesecondcharacterwas theplanthabit(eithergroundrosette/lowerleaforclimbing vine/upperleaf).Foreachplantineachofthefourcategories three variables were established with a measuring tape: leaf width(maximumwidthofthephyllodium),leaflength(length ofthephyllodium)and length ofthepetiole.Onlyonefully grown leaf bearing a functional pitcher per clonal plant was usedtoavoidpseudoreplication.Theratiosof(a)leaflength toleafwidthand(b)leaflengthtopetiolelengthwerecompared among the four categories to address genetic rather thanenvironmentaleffectsonleafshape.Thedatadidnot meettheassumptionsofparametricanalysis(i.e.,normality andhomoscedasticity),thusnon-parametriccomparisonsof teststatisticswereperformed.AllstatisticsweredoneinR(R DevelopmentCoreTeam2011). Voucher specimens representing these plants were collected inBruneiDarussalamandwillbedepositedatL(seeTable1). Collector&Number Taxon Country Sitename Collectiondate Herbarium M. Scharmann 1101 Nepenthes rafflesianaJack BruneiDarussalam BadasPSF 14May2011 L M. Scharmann 1102 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasPSF 14May2011 L M. Scharmann 1103 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasHeath/Lumutsite 20May2011 L M. Scharmann 1104 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasHeath/Lumutsite 21May2011 L M. Scharmann 1105 Nepenthes ampullariaJackxNepenthes hemsleyanaMacfarl. BruneiDarussalam BadasHeath/Lumutsite 22May2011 L M. Scharmann 1106 Nepenthes x hookerianaLindl. BruneiDarussalam BadasHeath/Lumutsite 23May2011 L M. Scharmann 1107 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasHeath/Lumutsite 24May2011 L M. Scharmann 1108 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasHeath/Lumutsite 25May2011 L M. Scharmann 1109 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasHeath/Lumutsite 26May2011 L M. Scharmann 1110 Nepenthes rafflesianaJack BruneiDarussalam BadasPSF June2011 L M. Scharmann 1111 Nepenthes rafflesianaJack BruneiDarussalam BadasPSF June2011 L M. Scharmann 1112 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasPSF June2011 L M. Scharmann 1113 Nepenthes hemsleyanaMacfarl. BruneiDarussalam BadasPSF June2011 L Table 1Voucherspecimens. 10 Blumea – Volume 58 / 1, 2013 Taxonomic treatment Nepenthes hemsleyana Macfarl. Nepenthes hemsleyanaMacfarl.(1908)61.—Type:Burbidge s.n.(lecto, designatedhere,KAcc.No.K000651485;isoKAcc.Nos.K000651484 and K000651486), Borneo, Sarawak, Lawas River, 1877. (http://apps. kew.org/herbcat/getImage.do?imageBarcode=K000651484, http://apps. kew.org/herbcat/getImage.do?imageBarcode=K000651485 and http:// apps.kew.org/herbcat/getImage.do?imageBarcode=K000651486,last accessed30May2012). Nepenthes rafflesianaJackvar. subglandulosaJ.H.Adam&Hafiza(Adam &Hamid2006)348.—Type:JHA8333(holoUKMB,n.v.;isoUKMB,n.v.), SarawakStateofMalaysia,Miri,LambirHill,alongtheroadtoTelekom MalaysiaReceivingStation,growinginopenvegetationwithN. gracilis and dominated by thicket of fern Dicranopteris linearis. Nepenthes baramensisC.Clarke,J.A.Moran&Chi.C.Lee(2011)230.—Type: Hotta M. 12419 (SAR,n.v.),Brunei,BelaitDistrict,Seria,enrouteK.Badas toSeriaalongtherailwayofB.S.C.,7Dec.1963. Etymology.ThespecificepithethonoursKewbotanistWilliamBotting Hemsley(1843–1924),whodescribedN. macfarlanei Hemsl.in1905.  Distribution—Borneo:BaramdistrictandBintuluareaof Sarawak,andBelaitandTutongdistrictsofBrunei(Clarkeet al.2011,pers.observ.).ProbablymorewidespreadonBorneo, butseediscussionbelow.  Hybrids—InBrunei, N. ampullaria Jack × hemsleyana (M. Scharmann 1105)andN. hemsleyana × rafflesiana have been documented, but occur only in habitats resulting from anthropogenicdisturbance.Theformerisdistinctfromsympatric N. × hookerianaLindl.(M. Scharmann 1106)inthepresence ofawaxyzone,hairsontheuppersideofthelid(seeTable2) andthenarrowerperistome.  Note—A very accurate description of N. hemsleyana is already available in the description of its heterotypic synonym N. baramensis(Clarkeetal.2011).Seethesamepublication for further specimens, informal synonyms, further notes and a table to distinguish it from N. rafflesiana.Thepresentstudyled totheidentificationofseveraladditionalcharacteristics(Table2). RESuLTS And dISCuSSIon Investigatingplantsin situ in Brunei, leaf shapes and proportionswerefoundtobedifferentbetweenplantswithawaxyzone inupperpitchers(representingN. hemsleyana)andthosewithoutawaxyzoneinupperpitchers(representingN. rafflesiana) (Fig.1).TheupperleavesofN. rafflesiana were proportionally wider than those of N. hemsleyana, while no such difference existedbetweenthelowerleaves(Fig.2a,Kruskal-Wallistest;χ2 (df=3,n=64)=28.862;p<0.001;post-hocpairedWilcoxontestswithBonferronicorrection).Furthermore,petiolesofupper leaves of N. rafflesiana were proportionally longer than those of N. hemsleyana, with again no such difference in the lower leaves(Fig.2b,Kruskal-Wallistest;χ2(df=3,n=64)=31.230; p<0.001;post-hocpairedWilcoxon-testswithBonferronicorrection).Therewasalsoasignificantdifferenceintheratioof leaf width to petiole length between lower and upper leaves, but thistraitwassharedbybothspecies(Fig.2c,Kruskal-Wallis test;χ2(df=3,n=64)=23.880;p<0.001;post-hocpaired Wilcoxon-testswithBonferronicorrection). Interpretingtheseresultsintermsofdevelopmentalchanges duringthespecies’ontogeny,itappearsthatleavesofboth N. hemsleyana and N. rafflesiana become more narrow relative to the petiole length after changing from rosette into climbing phase.However,N. rafflesiana leaves become wider relative to length and are borne on a relatively longer petiole, while N. hemsleyanadoesnotchangetheseproportionssignificantly. Thisfindingaddsleafcharacterdifferencestothedifferences inpitchershapeontogenyreportedby Gaume & Di Giusto (2009): while N. rafflesiana gradually reduces the extent of thewaxyzoneduringplantdevelopmentandapproachesan ovoid lower pitcher shape, N. hemsleyana retains or extends thewaxyzonethroughoutitslifeandalsoretainstheelongate lowerpitchershape. Wedisagree with Macfarlane’s opinion that the longitudinal leafveins(‘nerves’)areakeydifferenceofN. rafflesiana and N. hemsleyana.Nepenthes rafflesiana is described with 5 pairs (Macfarlane1908),4–5pairs(Danser1928)or3–5pairsof longitudinalveins(Cheek&Jebb2001),whileN. hemsleyana resp.itssynonymsaredescribedwith4–5pairs(Macfarlane 1908),3–5pairs(Clarkeetal.2011)or2pairs(Adam&Hamid 2006). Furthermore, Macfarlane (1908) describes the veins in N. hemsleyana as situated relatively closer to the midrib (ourinterpretationofhisdistancemeasurements),butinour vouchers their relative positions are similar for both species (measureatwidest point ofleaf). Inthevoucherscollected for this study, all specimens of N. hemsleyanahad3pairs(15 lowerandupperleavesfrom7specimens),whilespecimens of N. rafflesianahad4–5(9lowerandupperleavesfrom3 specimens).Consideringtheseslightdifferences,andtheinconsistent earlier reports, we conclude that the leaf veins are notareliabledistinctivecharacteristic. ItispossiblethatN. hemsleyana has a much wider distribution thancurrentlyknown,sincepotentialhabitat(lowlandkerangas, peatswampforest)iswidespreadonBorneo,orhasbeenso beforehumanalteration.Thespeciesmightpersistaroundthe type locality in the Lawas district of Sarawak, close to the coast andthebordertoSabah.However,thisareahasundergone severe environmental change since the visit by Burbidge in the 1870s.Anderson(1963)notestheoccurrenceofauniquetype Characteristic N. hemsleyana N. rafflesiana Lowerleaves Oblanceolate,acute,leafapexclearlydistinctfromtendril, Oblanceolate,acuminateorleafapexambiguous,tendrilfrequently  tendrilalwaysround,Fig.1d flattened/winged,tendrilwingscontinuouslymergingintoleafmargins   andthepitcherwings,Fig.1c(extremelybroadtendrilwings:described as N. rafflesianavar.alataJ.H.Adam&Wilcock) Upperleaves Linear,3.0–7.3timesaslongaswide,1.4–5.1timesas Oblong,2.2–4.6timesaslongaswide,1.7–2.8timesaslongasthe  longasthepetiole,Fig.1b petiole,Fig.1a Lidsofadultlowerpitchers Frequentlywith2ormore5–10mmlongfiliformappendageson Neverwithsuchfiliformappendages upper surface, appendages multicellular, positioned towards the posterior lid margin and usually close to the spur, sometimes on the spur, resembling those in juvenile pitchers and N. tentaculata  Hook.f.(presentinM. Scharmann Nos. 1104, 1107, 1108, 1112) Colour of leaves in closed Dark green, reddish Bright green forest(peatswampand kerangas) Table 2 Further characteristics that separate N. hemsleyana from N. rafflesiana, supplementing the characteristics presented in the description of N. baramensis(Clarkeetal.2011:Table2). 11 M.Scharmann&T.U.Grafe:ReinstatementofNepenthes hemsleyana of peat swamp, dominated by species of Dacrydium and Casuarina.Yetalreadyinthe1960slittleofthisremained.Inspection ofsatelliteimagery(GoogleEarth,GoogleInc;imagecover partlydated4July2007,partlyundated)andapersonalvisit to the locality in 2011 showed that almost all forest has been clearedandreplacedbyoilpalmplantations.Therearetwohills closetotheMerapokRiverthatcouldcorrespondtotheone Burbidgeclimbed(Burbidge1880).Bothofthemhavebeen logged, while the steeper one is partly ablated as a sand quarry andthevegetationheavilydegradedbyburning.Nepenthes hemsleyana could not be located, but might survive in small pocketsofnaturalvegetationinthegeneralarea. Danser(1928)mentionedtheunusualdeviationofHallier B 1459(seeabove,collectedfromtheKenepaiRiver,atributary oftheKapuasinWestKalimantan,c.N0°38'E111°48')fromthe description of N. rafflesiana.Are-examinationofthismaterialat BOisneededtoclarifywhetheritrepresentsN. hemsleyana. Furthermore,photosshowingplantswithpitcherssuperficially resembling the species but with extremely narrow phyllodia haveappearedfromtheKapuas (http://tanamanbuas.proboards.com/index.cgi?board=habitat&action=display&thread =2866&page=2,accessed30May2012). cN. rafflesiana lower leaf bN. hemsleyana upper leaf aN. rafflesiana upper leaf 10 cm 10 cm 10 cm 10 cm dN. hemsleyana lower leaf Fig. 1Characteristicshapeofupperandlowerleaves.a.N rafflesianaupperleaf;b.N. hemsleyanaupperleaf;c.N. rafflesianalowerleaf;d.N. hemsleyana lowerleaf.Drawnfromdriedmaterial(M. Scharmann 1110, 1111, 1112, 1113,plantsgrowingincloseproximity),scaledtothesamelengthofpetioleplusleaf. c b d a box legend: no waxy zone in upper pitchers (N. rafflesiana) waxy zone in upper pitchers (present N. hemsleyana) a ab c b 2 3 4 5 6 7 leaf length / leaf width a lower leaves upper leaves n=11 n=33 n=14 n=6 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 leaf width / petiole length ca ab bc c lower leaves upper leaves n=11 n=33 n=14 n=6 2 4 6 8 leaf length / petiole length bab bc d ac lower leaves upper leaves n=11 n=33 n=14 n=6 Fig. 2 Leaf proportions of N. hemsleyana and N. rafflesiana.a.Ratioofleaflengthtoleafwidth;b.ratioofleaflengthtopetiolelength;c.ratioofleafwidthto petiolelength.Box-whiskerplotsbasedonthemedian,quartilesandextremeswithinquartileplus1.5×IQR,outliersshownasdots.Thesmalllettersabovedata illustrateasignificantdifference(letternotshared)resp.similarity(lettershared)betweengroups,resultingfrommultiplepairedcomparisons(statisticsseetext). cba 12 Blumea – Volume 58 / 1, 2013 Regardingthepracticalapplicationofthisstudy,weemphasise that N. hemsleyana tend to have relatively narrower leaves with relatively shorter petioles than N. rafflesiana(bothlowerand upperleaves),althoughabsolutelengthandwidthaswellas theratiosdooverlapandarethereforenon-exclusive.However, by examining this characteristic in combination with leaf shape (Fig.1),leafcolouration,tendrilinsertionandpresenceoflid hairsonlowerpitchers(Table2),N. hemsleyana and N. rafflesianacanusuallybeseparatedinthefieldevenwhenupper pitchers are unavailable, particularly when directly compared inthesamehabitat. To conclude, the taxonomic separation of N. hemsleyana and N. rafflesianaisjustifiedbytheirdifferentpitcherandleafmorphology,andconsequentlybydivergentphysiologyandecology. Although they often grow in close proximity to one another and share many traits, some traits are not randomly combined but linked(e.g.waxyzoneinupperpitcherswithnarrowerleaves), indicating a certain degree of reproductive isolation between thetwotaxa. AcknowledgementsTheauthorsthankthefamilyofAbdulHadzidHarith TinggalandIeney Daud (TelambaHomestay), as wellasYen Shan Lim andfamily, fortheir helpand supportin all logisticalmatters in Brunei. WalterFederle,DanielG.ThornhamandJoannaM.Smitharethankedfor assistanceinthefield and beyond. Charles Clarke, D.G.Thornham and twoanonymousreviewersgavehelpfulcommentsonthemanuscript.The workin Brunei Darussalam wasconducted underresearch permitUBD/ PSR/5.1andNepenthessampleswereexportedunderCITESpermitNo. BA/MAP/191/1108.FundingwasprovidedbyagrantfromtheLeverhulme Trust(F/09364/G)andaDAADstipendtoM.S. REFEREnCES AdamJH,HamidHA.2006.PitcherplantsofLambirHillinMiri,Sarawak StateofMalaysia.InternationalJournalofBotany2:340–352.doi:10.3923/ ijb.2006.340.352. 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