Nepenthes gracilis

Nepenthes gracilis (/nɪˈpɛnθiːz ˈɡræsɪlɪs/; from Latin: gracilis "slender"), or the slender pitcher-plant,^[5] is a common lowland pitcher plant that is widespread in the Sunda region. It has been recorded from Borneo, Cambodia,^[6] Peninsular Malaysia, Singapore, Sulawesi, Sumatra, and Thailand.^{[7][8][9][10][11]} The species has a wide altitudinal distribution of 0 to 1100 m^[12] (and perhaps even 1700 m^[13]) above sea level, although most populations are found below 100 m and plants are rare above 1000 m.^[13] Despite being a widespread plant, natural hybrids between N. gracilis and other species are quite rare.

Nepenthes gracilis
A pitcher of Nepenthes gracilis from Terengganu, Peninsular Malaysia
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Nepenthaceae
Genus:	Nepenthes
Species:	N. gracilis
Binomial name
Nepenthes gracilis Korth. (1839)[2]
Synonyms
Synonyms Nepenthes angustifolia Mast. (1881)[3] Nepenthes distillatoria auct. non L.: Jack (1835) Nepenthes distillatoria auct. non L.: Wall. (1828) [=N. distillatoria/N. gracilis] Nepenthes korthalsiana Miq. (1858) Nepenthes laevis Lindl. (1848) Nepenthes laevis Korth. ex Hook.f. in DC. (1873) Nepenthes longinodis Beck (1895)[4] Nepenthes obrieniana Linden & Rodigas (1890) nom.ambiguum [=?(N. gracilis × (N. rafflesiana × N. hirsuta)) × N. distillatoria/ N. gracilis/N. mirabilis] Nepenthes teysmanniana Miq. (1858) [=N. albomarginata/N. gracilis]

Nepenthes gracilis was formally described by Pieter Willem Korthals in his 1839 monograph, "Over het geslacht Nepenthes".^[2]

Nepenthes abgracilis from the Philippines is named for its superficial similarity to this species.^[14]

Carnivory

The small, elongated pitchers of N. gracilis appear relatively unremarkable and have a very thin peristome. Nevertheless, the species is unusual (and possibly unique) in that the underside of the pitcher lid bears an uneven layer of wax crystals. This layer is not as thick as, and structurally distinct from, that found in the waxy zone of the pitcher interior, and insects can easily adhere to it in dry conditions. During downpours, however, it functions as part of a trapping mechanism, whereby the impact of raindrops striking the lid causes insects to lose their footing and fall into the pitcher cup below.^[15]

Left: Nepenthes gracilis upper pitcher with a Polyrhachis pruinosa ant (A and B), showing the waxy zones of the pitcher interior and lower lid surface.

Centre: Scanning electron micrographs revealing the ultrastructure of N. gracilis wax crystals on the inner surface of the pitcher (A and B) and underside of the lid (C and D).

Right: Prey capture efficiency of the two waxy layers and peristome of N. gracilis under 'dry', 'raining' and 'wet' conditions.

Trapping function of N. gracilis pitcher lid under experimental conditions^[15]

• Ants being flicked off the waxy lower surface of the lid by the action of simulated rain
• The same experiment carried out with an isolated lid held in place with a paper clip
• High-speed recording showing a house fly (Musca domestica) falling into a pitcher following raindrop impact (recording frame rate: 428 s⁻¹, playback frame rate: 10 s⁻¹)

Distribution

Nepenthes gracilis habitat in Pahang, Peninsular Malaysia

One of the most widespread Nepenthes species, N. gracilis is native to Borneo, Cambodia,^[6] Peninsular Malaysia, Singapore, Sumatra, central Sulawesi, and southernmost Thailand.^[7] It has also been recorded from many smaller islands, including Bangka, Batu Islands, Belitung,^[16] Bengkalis, Ko Lanta, Ko Tarutao, Labuan,^[17] Langkawi, Mendol, Mentawai Islands (Siberut), Meranti Islands (Padang, Rangsang, and Tebing Tinggi), Musala, Nias, Penang, Phuket, Riau Islands (Lingga Islands, Natuna Islands,^[18] and Riau Archipelago), and Rupat.^[19]

Evolutionary origins

In 2001, Charles Clarke performed a cladistic analysis of the Nepenthes species of Sumatra and Peninsular Malaysia using 70 morphological characteristics of each taxon. The following is a portion of the resultant cladogram, showing part of "Clade 6", which includes N. gracilis.^[20]

	unnamed N. gracilis N. reinwardtiana unnamed N. tobaica 79% N. angasanensis N. mikei

When molecular genetic DNA sequence data instead of morphological characters are used to perform similar analyses,^[21][22] it becomes evident that N. gracilis is not closely related to any of these 4 species. Rather, N. gracilis is the basal lineage within a "N. mirabilis group", a clade that also includes N. bicalcarata, a group of species around N. tomoriana (several species from Sulawesi, Papua and New Caledonia), N. ampullaria, N. mirabilis and N. rafflesiana sensu lato. The contrast between molecular and morphological phylogenies implies that the morphological characters evolved quite fast and repeatedly, and do not necessarily reflect shared ancestry of the species.

Infraspecific taxa

Despite varying little across its range,^[20] N. gracilis has a number of infraspecific taxa. Most of these are no longer considered valid.

• Nepenthes gracilis f. angustifolia (Mast.) Hort.Westphal (1993)
• Nepenthes gracilis var. angustifolia (Mast.) Hort.Weiner in sched. (1985)
• Nepenthes gracilis var. arenaria Ridl. ex Macfarl. (1908)^[23]
• Nepenthes gracilis var. elongata Blume (1852)^[24]
• Nepenthes gracilis var. longinodis Beck (1895)^[4]
• Nepenthes gracilis var. major Hort.Van Houtte ex Rafarin (1869)
• Nepenthes gracilis var. teysmanniana (Miq.) Beck (1895)^[4]

Natural hybrids

The following natural hybrids involving N. gracilis have been recorded.

• N. albomarginata × N. gracilis
• N. ampullaria × N. gracilis [=N. × trichocarpa]^[25]
• (N. ampullaria × N. gracilis) × N. bicalcarata [=N. × trichocarpa × N. bicalcarata]
• N. bicalcarata × N. gracilis [=N. × cantleyi]^[25]
• ? N. eustachya × N. gracilis^[7]
• N. gracilis × N. mirabilis [=N. × sharifah-hapsahii, N. × ghazallyana, N. × grabilis, N. neglecta?]^[7][25][26]
• N. gracilis × N. northiana [=N. × bauensis]^[27]
• N. gracilis × N. rafflesiana^[25][28][29]
• N. gracilis × N. reinwardtiana^[20]
• N. gracilis × N. sumatrana^[7]

• 
  N. albomarginata × N. gracilis
• 
  N. ampullaria × N. gracilis
• 
  N. bicalcarata × N. gracilis
• 
  ? N. eustachya × N. gracilis
• 
  N. gracilis × N. mirabilis
• 
  N. gracilis × N. northiana
• 
  N. gracilis × N. rafflesiana
• 
  N. gracilis × N. sumatrana

References

1. Clarke, C.M. (2018). "Nepenthes gracilis". IUCN Red List of Threatened Species. 2018: e.T39663A143960417. doi:10.2305/IUCN.UK.2018-1.RLTS.T39663A143960417.en. Retrieved 19 November 2021.
2. (in Dutch) Korthals, P.W. 1839. Over het geslacht Nepenthes. In: C.J. Temminck 1839–1842. Verhandelingen over de Natuurlijke Geschiedenis der Nederlandsche overzeesche bezittingen; Kruidkunde. Leiden. pp. 1–44, t. 1–4, 13–15, 20–22.
3. Masters M.T. (1881). "New garden plants. Nepenthes angustifolia (Mast.), sp. nov". The Gardeners' Chronicle. 16 (408): 524.
4. (in German) Beck, G. 1895. Die Gattung Nepenthes. Wiener Illustrirte Garten-Zeitung 20(3–6): 96–107, 141–150, 182–192, 217–229.
5. Phillipps, A. & A. Lamb 1996. Pitcher-Plants of Borneo. Natural History Publications (Borneo), Kota Kinabalu.
6. Mey, F.S. 2016. The beautiful Nepenthes kampotiana x bokorensis. Strange Fruits: A Garden's Chronicle, 5 October 2016.
7. McPherson, S.R. 2009. Pitcher Plants of the Old World. 2 volumes. Redfern Natural History Productions, Poole.
8. McPherson, S.R. & A. Robinson 2012. Field Guide to the Pitcher Plants of Sulawesi. Redfern Natural History Productions, Poole.
9. McPherson, S.R. & A. Robinson 2012. Field Guide to the Pitcher Plants of Borneo. Redfern Natural History Productions, Poole.
10. (in Italian) Catalano, M. 2010. Nepenthes della Thailandia: Diario di viaggio. Prague.
11. McPherson, S.R. & A. Robinson 2012. Field Guide to the Pitcher Plants of Sumatra and Java. Redfern Natural History Productions, Poole.
12. McPherson, S.R. & A. Robinson 2012. Field Guide to the Pitcher Plants of Peninsular Malaysia and Indochina. Redfern Natural History Productions, Poole.
13. Adam, J.H., C.C. Wilcock & M.D. Swaine 1992. "The ecology and distribution of Bornean Nepenthes" (PDF). Archived from the original (PDF) on 2011-07-22. Journal of Tropical Forest Science 5(1): 13–25.
14. Cheek M., Jebb M. (2013). "The Nepenthes micramphora (Nepenthaceae) group, with two new species from Mindanao, Philippines". Phytotaxa. 151 (1): 25–34. doi:10.11646/phytotaxa.151.1.2.
15. Bauer U., Di Giusto B., Skepper J., Grafe T.U., Federle W. (2012). "With a flick of the lid: a novel trapping mechanism in Nepenthes gracilis pitcher plants". PLOS ONE. 7 (6): e38951. Bibcode:2012PLoSO...738951B. doi:10.1371/journal.pone.0038951. PMC 3374759. PMID 22719998.{{cite journal}}: CS1 maint: multiple names: authors list (link)
16. (in Indonesian) Hidayat, S., J. Hidayat, Hamzah, E. Suhandi, Tatang & Ajidin 2003. Analisis vegetasi dua jenis tumbuhan pemakan serangga di Padang Pinang Anyang, Pulau Belitung. [Vegetation analysis of two insectivorous plants in Padang Pinang Anyang, Belitung Island.] Biodiversitas 4(2): 93–96.
17. Burbidge F.W. (1882). "Notes on the new Nepenthes". The Gardeners' Chronicle. 17 (420): 56.
18. (in Indonesian) Mansur, M. 2012. Keanekaragaman jenis tumbuhan pemakan serangga dan laju fotosintesisnya di Pulau Natuna. [Diversity on insectivorous plants and its photosynthetic rate in Natuna Island.] Berita Biologi 11(1): 33–42. Abstract Archived 2013-09-21 at the Wayback Machine
19. Clarke, C.M. 2001. Appendix C: Distribution Maps. In: Nepenthes of Sumatra and Peninsular Malaysia. Natural History Publications (Borneo), Kota Kinabalu. pp. 299–307.
20. Clarke, C.M. 2001. Nepenthes of Sumatra and Peninsular Malaysia. Natural History Publications (Borneo), Kota Kinabalu.
21. Scharmann, Mathias; Wistuba, Andreas; Widmer, Alex (October 2021). "Introgression is widespread in the radiation of carnivorous Nepenthes pitcher plants". Molecular Phylogenetics and Evolution. 163: 107214. doi:10.1016/j.ympev.2021.107214. hdl:20.500.11850/494608. ISSN 1095-9513. PMID 34052438.
22. Murphy, Bruce; Forest, Félix; Barraclough, Timothy; Rosindell, James; Bellot, Sidonie; Cowan, Robyn; Golos, Michal; Jebb, Matthew; Cheek, Martin (March 2020). "A phylogenomic analysis of Nepenthes (Nepenthaceae)". Molecular Phylogenetics and Evolution. 144: 106668. doi:10.1016/j.ympev.2019.106668. ISSN 1095-9513. PMID 31682924.
23. Macfarlane, J.M. 1908. Nepenthaceae. In: A. Engler. Das Pflanzenreich IV, III, Heft 36: 1–91.
24. (in Latin) Blume, C.L. 1852. Ord. Nepenthaceae. In: Museum Botanicum Lugduno-Batavum, sive stirpium exoticarum novarum vel minus cognitarum ex vivis aut siccis brevis expositio. Tom. II. Nr. 1. E.J. Brill, Lugduni-Batavorum. pp. 5–10.
25. Clarke, C.M. 1997. Nepenthes of Borneo. Natural History Publications (Borneo), Kota Kinabalu.
26. Fretwell S (2013). "Back in Borneo to see giant Nepenthes. Part 2: Mt Tambuyukon and Poring". Victorian Carnivorous Plant Society Journal. 108: 6–15.
27. Lee, C.C. 2004. Nepenthes. In: Sarawak Bau Limestone Biodiversity. H.S. Yong, F.S.P. Ng and E.E.L. Yen (eds). The Sarawak Museum Journal Vol. LIX, No. 80; Special Issue No. 6: 71–77.
28. Tan W.K., Wong C.L., Frazier C.K. (1996). "Nepenthes × (rafflesiana and gracilis)?". Nature Malaysiana. 21: 82–85.{{cite journal}}: CS1 maint: multiple names: authors list (link)
29. Bednar, B.L. 1985. "Nepenthes ✕ dominii and var. intermedia" (PDF). Carnivorous Plant Newsletter 14(4): 105–106.

Further reading

• Adam, J.H. 1997. "Prey spectra of Bornean Nepenthes species (Nepenthaceae) in relation to their habitat" (PDF). Pertanika Journal of Tropical Agricultural Science 20(2–3): 121–134.
• Adam, J.H. & C.C. Wilcock 1999. "Palynological study of Bornean Nepenthes (Nepenthaceae)" (PDF). Pertanika Journal of Tropical Agricultural Science 22(1): 1–7.
• Adam J.H., Nurulhuda E.M., Abdul-Halim H., Abdul-Rahim O., Hafiza A.H., Gopir G.K., Pilik L.M., Omar R., Qasim M.B., Salimon J., Abdul-Rahim S., Hanafiah M.M. (2005). "Pitcher plants recorded from BRIS forest in Jambu Bongkok, Kuala Trengganu, Malaysia". Wetland Science. 3 (3): 183–189.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• (in Malay) Adam, J.H., J.N. Maisarah, A.T.S. Norhafizah, A.H. Hafiza, M.Y. Harun & O.A. Rahim et al. 2009. Ciri Tanih Pada Habitat Nepenthes (Nepenthaceae) di Padang Tujuh, Taman Negeri Endau-Rompin Pahang. [Soil Properties in Nepenthes (Nepenthaceae) Habitat at Padang Tujuh, Endau-Rompin State Park, Pahang.] In: J.H. Adam, G.M. Barzani & S. Zaini (eds.) Bio-Kejuruteraan and Kelestarian Ekosistem. [Bio-Engineering and Sustainable Ecosystem.] Kumpulan Penyelidikan Kesihatan Persekitaran, Pusat Penyelidikan Bukit Fraser and Universiti Kebangsaan, Malaysia. pp. 147–157.
• (in Indonesian) Akhriadi, P. 2007. Kajian taksonomi hibrid alami Nepenthes (Nepenthaceae) di Kerinci. Working paper, Andalas University, Padang.
• Koji Matsumoto (2004). "Enzymic and structural characterization of nepenthesin, a unique member of a novel subfamily of aspartic proteinases". Biochemical Journal. 381 (Pt 1): 295–306. doi:10.1042/BJ20031575. PMC 1133788. PMID 15035659.
• Aung H.H., Chia L.S., Goh N.K., Chia T.F., Ahmed A.A., Pare P.W., Mabry T.J. (2002). "Phenolic constituents from the leaves of the carnivorous plant Nepenthes gracilis". Fitoterapia. 73 (5): 445–447. doi:10.1016/S0367-326X(02)00113-2. PMID 12165348.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• (in Indonesian) Baloari, G., R. Linda & Mukarlina 2013. Keanekaragaman jenis dan pola distribusi Nepenthes spp di Gunung Semahung Kecamatan Sengah Temila Kabupaten Landak. Protobiont 2(1): 1–6. Abstract
• Bauer U., Clemente C.J., Renner T., Federle W. (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. PMID 22023155.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Beaman, J.H. & C. Anderson 2004. The Plants of Mount Kinabalu: 5. Dicotyledon Families Magnoliaceae to Winteraceae. Natural History Publications (Borneo), Kota Kinabalu.
• Bonhomme V., Pelloux-Prayer H., Jousselin E., Forterre Y., Labat J.-J., Gaume L. (2011). "Slippery or sticky? Functional diversity in the trapping strategy of Nepenthes carnivorous plants". New Phytologist. 191 (2): 545–554. doi:10.1111/j.1469-8137.2011.03696.x. PMID 21434933.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Bourke, G. 2010. "The climbing pitcher plants of the Kelabit highlands" (PDF). Archived from the original (PDF) on 2013-04-09. Retrieved 2012-10-21. Captive Exotics Newsletter 1(1): 4–7.
• Brearley F.Q., Mansur M. (2012). "Nutrient stoichiometry of Nepenthes species from a Bornean peat swamp forest". Carnivorous Plant Newsletter. 41 (3): 105–108. doi:10.55360/cpn413.fb162. S2CID 247076533.
• Buch F., Rott M., Rottloff S., Paetz C., Hilke I., Raessler M., Mithöfer A. (2012). "Secreted pitfall-trap fluid of carnivorous Nepenthes plants is unsuitable for microbial growth". Annals of Botany. 111 (3): 375–383. doi:10.1093/aob/mcs287. PMC 3579442. PMID 23264234.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Chia T.F., Aung H.H., Osipov A., Goh N.K., Chia L.S. (2004). "Carnivorous pitcher plant uses free radicals in the digestion of prey". Redox Report. 9 (5): 255–261. doi:10.1179/135100004225006029. PMID 15606978.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Chou L.Y., Clarke C.M., Dykes G.A. (2014). "Bacterial communities associated with the pitcher fluids of three Nepenthes (Nepenthaceae) pitcher plant species growing in the wild". Archives of Microbiology. 196 (10): 709–717. Bibcode:2014ArMic.196..709C. doi:10.1007/s00203-014-1011-1. PMID 25005571. S2CID 14710734.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Chua T.J.L., Lim M.L.M. (2012). "Cross-habitat predation in Nepenthes gracilis: the red crab spider Misumenops nepenthicola influences abundance of pitcher dipteran larvae". Journal of Tropical Ecology. 28 (1): 97–104. doi:10.1017/S0266467411000629. S2CID 86412691.
• Chung, A.Y.C. 2006. Biodiversity and Conservation of The Meliau Range: A Rain Forest in Sabah's Ultramafic Belt. Natural History Publications (Borneo), Kota Kinabalu. ISBN 9838121169.
• (in Indonesian) Deswita, E. 2010. Perkembangan ginesium beberapa jenis Nepenthes (N. ampullaria Jack., N. gracilis Korth. dan N. reinwardtiana Miq.).Thesis, Andalas University, Padang.
• Dixon W.E. (1889). "Nepenthes". The Gardeners' Chronicle. 3. 6 (144): 354.
• (in Indonesian) Enjelina, W. 2012. Analisis hibrid alam kantung semar (Nepenthes) di Bukit Taratak Kabupaten Pesisir Selatan Sumatera Barat dengan teknik RAPD. M.Sc. thesis, Andalas University, Padang.
• Fan D.-H., Wang H., Zhi D., Shen Y.-M. (2010). "CE analysis of endogenous flavonoid gallate esters from Nepenthes gracilis (Nepenthaceae)". Chromatographia. 72 (9–10): 1013–1016. doi:10.1365/s10337-010-1729-0. S2CID 95590457.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Fashing, N.J. 2010. "Two novel adaptations for dispersal in the mite family Histiostomatidae (Astigmata)" (PDF). In: M.W. Sabelis & J. Bruin (eds.) Trends in Acarology: Proceedings of the 12th International Congress. Springer Science, Dordrecht. pp. 81–84. doi:10.1007/978-90-481-9837-5
• Frazier, C.K. 2000. Reproductive isolating mechanisms and fitness among tropical pitcher plants (Nepenthes) and their hybrids. [video] The 3rd Conference of the International Carnivorous Plant Society, San Francisco, USA.
• (in Indonesian) Handayani, T. 1999. "Konservasi Nepenthes di kebun raya Indonesia" (PDF). [Conservation of Nepenthes in Indonesian botanic gardens.] In: A. Mardiastuti, I. Sudirman, K.G. Wiryawan, L.I. Sudirman, M.P. Tampubolon, R. Megia & Y. Lestari (eds.) Prosiding II: Seminar Hasil-Hasil Penelitian Bidang Ilmu Hayat. Pusat Antar Universitas Ilmu Hayat IPB, Bogor. pp. 365–372.
• (in Indonesian) Harahap, A.S. 2010. Mikropropogasi tunas kantong semar (Nepenthes gracillis Korth.) dengan pemberian NAA dan BAP secara in vitro. Student paper, University of North Sumatra, Medan.
• Hernawati & P. Akhriadi 2006. A Field Guide to the Nepenthes of Sumatra. PILI-NGO Movement, Bogor.
• Hooker J.D. (1859). "XXXV. On the origin and development of the pitchers of Nepenthes, with an account of some new Bornean plants of that genus". The Transactions of the Linnean Society of London. 22 (4): 415–424. doi:10.1111/j.1096-3642.1856.tb00113.x.
• Hwee K.C. (1996). "Carnivorous plants and sites in Singapore". Bulletin of the Australian Carnivorous Plant Society, Inc. 15 (4): 12–15.
• Kadek A., Tretyachenko V., Mrazek H., Ivanova L., Halada P., Rey M., Schriemer D.C., Man P. (2014). "Expression and characterization of plant aspartic protease nepenthesin-1 from Nepenthes gracilis". Protein Expression and Purification. 95: 121–128. doi:10.1016/j.pep.2013.12.005. PMID 24365662.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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• Kato, M., M. Hotta, R. Tamin & T. Itino 1993. Inter- and intra-specific variation in prey assemblages and inhabitant communities in Nepenthes pitchers in Sumatra. Tropical Zoology 6(1): 11–25. Abstract
• Kitching, R.L. 2000. Food Webs and Container Habitats: The natural history and ecology of phytotelmata. Cambridge University Press, Cambridge.
• Kurup R., Johnson A.J., Sankar S., Hussain A.A., Kumar C.S., Baby S. (2013). "Fluorescent prey traps in carnivorous plants". Plant Biology. 15 (3): 611–615. Bibcode:2013PlBio..15..611K. doi:10.1111/j.1438-8677.2012.00709.x. PMID 23696970.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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• Ma Hnin Hnin Aung 2004. Phenolic compounds from Nepenthes gracilis Korth: isolation, identification and antioxidant studies. Ph.D. thesis, Nanyang Technological University, Singapore.
• Macfarlane J.M. (1914). "Family XCVI. Nepenthaceæ. In: J.S. Gamble. Materials for a flora of the Malayan Peninsula, No. 24". The Journal of the Asiatic Society of Bengal. 75 (3): 279–391 [279–288].
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• (in Indonesian) Mansur, M. 2008. Penelitian ekologi Nepenthes di Laboratorium Alam Hutan Gambut Sabangau Kereng Bangkirai Kalimantan Tengah Archived 2016-03-04 at the Wayback Machine. [Ecological studies on Nepenthes at Peat Swamps Forest Natural Laboratory, Kereng Bangkirai Sabangau, Central Kalimantan.] Jurnal Teknologi Lingkungan 9(1): 67–73. Abstract
• Mansur M., Brearley F.Q. (2008). "Ecological studies on Nepenthes at Barito Ulu, Central Kalimantan, Indonesia". Jurnal Teknologi Lingkungan. 9 (3): 271–276. Archived from the original on 2012-07-08.
• Moore, D. 1872. On the culture of Nepenthes at Glasnevin. The Gardeners' Chronicle and Agricultural Gazette 1872(11): 359–360.
• Masters M.T. (1872). "The cultivated species of Nepenthes". The Gardeners' Chronicle and Agricultural Gazette. 1872 (16): 540–542.
• Meimberg H., Wistuba A., Dittrich P., Heubl G. (2001). "Molecular phylogeny of Nepenthaceae based on cladistic analysis of plastid trnK intron sequence data". Plant Biology. 3 (2): 164–175. Bibcode:2001PlBio...3..164M. doi:10.1055/s-2001-12897. S2CID 260252804.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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