1. Family: Nepenthaceae Dumort.
    1. Genus: Nepenthes L.
      1. Nepenthes thai Cheek

        This species is accepted, and its native range is Thailand.


    Cheek, M. & Jebb, M. 2009. Nepenthes group Montanae (Nepenthaceae) in Indo-China, with N. thai and N. bokor described as new. Kew Bulletin 64: 319. DOI: https://doi.org/10.1007/s12225-009-9117-3

    Thailand, Narathiwat, Sukhirin, Khao Nakharach, c. 600 m alt., fl. 8 Aug. 1996, Puudjaa 260 (holotypus [annotated “holotype”] BKF; isotypus BKF, photos K).
    Terrestrial climber 3 – 5 m tall. Rosette stems unknown
    Short stems terete, matt, 5 – 7 mm diam., internodes 0.5 – 1.5 cm long, axillary buds absent Climbing stems as the short stems, but 4 – 5 mm diam., internodes 1.5 – 3.0 cm long
    Leaves not petiolate, coriaceous, narrowly oblanceolate or narrowly oblong and subspatulate, pseudopetiolate, dilating at the node, 11.5 – 29 × 2.7 – 6 cm, the pseudopetiole, if present, 1.2 – 7 × c. 1.2 cm, blade apex broadly acute, peltate, the tendril departing 0.5 – 1 mm from the apex, base decurrent down the stem for 3 – 12 mm at an angle of c. 45° to the main axis, clasping the stem for ¾ -  of its circumference, projecting from the stem as wings 3 – 7 mm wide Leaves narrowly oblong-elliptic and spatulate/pseudopetiolate, 12.5 – 18 × 2.5 – 4 cm, pseudopetiolar part 2.5 – 3 cm long, 1.0 – 1.6 cm wide, dilating at the node to c. 1.7 cm wide, blade apex either peltate or with the tendril attached to the apex, clasping the stem for ¾ of its circumference Leaf blades with 10 – 30 appressed white hairs, best viewed in the unfurled leaf, but persisting, highly inconspicuous; blade apex sometimes moderately densely hairy, hairs sometimes extending along tendril to the pitcher, hairs white or grey, simple, 0.25 – 0.5 mm long
    Indumentum absent from stems, apart from sessile red glands c. 0.05 mm diam. which extend to the lower surface of the leaf-blades (c. 960 – 1600 per mm2) and exterior of pitchers
    Spur with hairs as the inflorescence Spur flattened, 4.5 – 6 mm long, divided to the base into two equal or unequal arms, apices of branches entire or bifurcate
    Inflorescence with dense grey hairs, partly appressed hairs 0.12 – 0.25 mm long, sparse on peduncle, dense, concealing surface, on rhachis, partial-peduncles, pedicels and outer surface of tepals, extending to inner surface margin, and androphores (rarely absent from the androphores), tepal nectar glands elliptic, 0.12 × 0.05 mm Female inflorescences, infructescences and seed not seen Male inflorescences often two per stem, borne at intervals of c. 5 internodes, 29 – 41 cm long; peduncle 7 – 10 (– 13) cm long, 3 mm diam. at base, often terminating with a variably shaped bract, sometimes foliose, to 9 × 4 mm; partial-peduncles (37 –) 60 – 100), 2-flowered, 2 – 4 mm long; bracts absent; pedicels 5 – 9 mm long; tepals elliptic 2 – 2.5 × 1.5 mm; androphore c. 2 mm long; anther head 0.75 × 1.2 mm, anthers 5 – 8
    General Description
    Colour on drying of short stems matt mid brown, climbing stems purple-black; leaves and pitchers pale grey-brown; live flowers recorded as red to brown (Puudjaa 260) Pitcher exterior with sparse red-brown and branched white simple hairs, c. 0.1 × 0.1 mm extending to the lid (rarely glabrous) and marginal 0.1 – 0.2 mm and apex of the lower lid Lower pitchers ovoid-cylindric, 8 – 11 × 3 – 4.4 cm, ovoid portion about ⅔ of the total length, thick-textured, cylindric portion 1.8 – 3.75 cm wide membranous, strongly wrinkled when dry with two fringed wings extending the length of the pitcher 3 – 4 mm wide, fringed elements 2 – 5 mm long, 6 – 8 per cm; mouth concave in profile, gradually rising over 2 – 4.5 cm from front to rear, column not distinct; peristome with outer edge entire, rarely sinuate, front part of the mouth with peristome subcylindrical, 1.2 – 1.5 mm wide, side of mouth with peristome flattened 2.5 – 4 mm wide; rear of mouth with peristome abruptly dilated to 7 – 9 mm wide at junction with the lid; ridges weakly but distinctly pronounced, 0.25 – 0.35 mm apart, c. 0.1 mm high, the inner edge generally lacking visible teeth Longitudinal nerves 5 – 7 cm each side of the midrib in the outer ⅔, conspicuous. Pennate nerves arising at c. 45° from the midrib, forming a reticulum with the longitudinal nerves, moderately conspicuous Lid elliptic, 2.5 – 4.5 × 2.25 – 2.6 cm, apex rounded, base rounded, lower surface lacking distinct appendages, but with a low keel along the midline, nectar glands sparse, elliptic, c. 0.5 mm long, along the keel, otherwise densely scattered (c. 480 per cm2) over the lower surface of the lid, crater-like, circular, 0.2 – 0.3 mm diam, decreasing slightly in size towards the margin, all but absent from marginal 2 mm Lid ovate-elliptic (1 –) 2.5 – 3.5 × (1.4 –) 2 – 2.4 cm, apex rounded or slightly emarginate, base rounded to slightly cordate, lower surface lacking a well developed keel or appendages, but sometimes with a slight keel (drying artefact?) terminating in a hairy area up to 2 mm long, raised up to 1 mm; nectar glands circular, scattered evenly over the lid, or with the midrib area bearing only a few sparse elliptic glands twice as long as the circular glands. Spur flattened 5 – 6 × 0.7 mm, apex rounded entire to 4-lacinate, inserted c. 4 mm below the peristome-lid junction Upper pitchers freely produced, resembling the lower pitchers but tendrils coiled, (7.5 –) 12 – 14 × (1.5 –) 3.8 – 4.2 cm, lower half narrowly infundibular, base curved upward 2 – 2.5 cm to meet the tendril, junction abrupt or gradual, upper half of pitcher cylindrical, (1.2 –) 2.2 – 2.6 cm wide, wings absent; peristome at front and side of mouth (0.5 –) 2 – 4 (–7) mm wide; teeth inconspicuous, obscured by curvature of inner peristome, when visible (0.1 –) 0.3 – 0.4 mm long, peristome ridges (0.15 –) 0.3 – 0.5 mm apart, each ridge separated by c. 5 microscopic lines Intermediate pitchers not seen
    Peninsular Thailand.
    Limestone hills; 500 – 600 m.
    Nepenthes thai is here assessed as Endangered (EN B2 ab(iii)) using the criteria of IUCN (2001) since it is known from only four sites (see above) within a small geographic area. Its limestone habitat in the Peninsula is threatened by mining for cement production, as such habitats are elsewhere in Malesia (Cheek & Jebb2001).
    Vegetative colour, rosette stems, female inflorescences, infructescences and seeds have still to be seen in Nepenthes thai. Moreover, although five collections were available, there has been little opportunity to study variation in some structures, such as the lower surface of the lid of the lower pitchers, for which only one lid was available. Therefore more collections and observations of this taxon would be welcome. In recent years access to specimen locations on the border with Malaysia has been hindered by security considerations. Named (noun in apposition) for Thailand.


    Native to:


    Nepenthes thai Cheek appears in other Kew resources:

    First published in Kew Bull. 64: 321 (2009)


    Kew Bulletin
    • Cheek, M. & Jebb, M. (2001). Nepenthaceae. Flora Malesiana 15, Leiden, Netherlands.Google Scholar
    • IUCN (2001). IUCN Red List Categories and Criteria: Version 3.1. Prepared by the IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK.Google Scholar
    • _____(2001). Nepenthes of Sumatra and Peninsular Malaysia. Natural History Publications (Borneo), Kota Kinabalu.Google Scholar
    • Clarke, C. (1999). Nepenthes benstonei (Nepenthaceae), a new pitcher plant from Peninsular Malaysia. Sandakania 13: 79 – 87.Google Scholar
    • Jebb, M. & Cheek, M. (1997). A skeletal revision of Nepenthes (Nepenthacaeae). Blumea 42: 1 – 106.Google Scholar
    • Danser, B. H. (1928). The Nepenthaceae of the Nederland Indies. Bull. Jard. Bot. Buitenzorg III, 9: 249 – 438.Google Scholar


    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Bulletin
    Kew Bulletin

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2020. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0