Nepenthes thai
Description
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. Leaves not petiolate, coriaceous, narrowly oblanceolate or narrowly oblong and subspatulate, pseudopetiolate, dilating at the node, 11.5 - 29 x 2.7 - 6 cm, the pseudopetiole, if present, 1.2 - 7 x 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 - 5/6 of its circumference, projecting from the stem as wings 3 - 7 mm wide. Longitudinal nerves 5 - 7 cm each side of the midrib in the outer 2/3 conspicuous. Pennate nerves arising at c. 45° from the midrib, forming a reticulum with the longitudinal nerves, moderately conspicuous. Lower pitchers ovoid-cylindric, 8 - 11 x 3 - 4.4 cm, ovoid portion about 2/3 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. Lid elliptic, 2.5 - 4.5 x 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. Spur flattened, 4.5 - 6 mm long , divided to the base into two equal or unequal arms, apices of branches entire or bifurcate. Intermediate pitchers not seen. Climbing stems as the short stems, but 4 - 5 mm diam., internodes 1.5 - 3.0 cm long. Leaves narrowly oblong-elliptic and spatulate/ pseudopetiolate, 12.5 - 18 x 2.5 - 4 cm, pseudopetiolar part 2.5 - 3 cm long, 1.0 - 1.6 cm wide, dilating at the nod e 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. Upper pitchers freely produced, resembling the lower pitchers but tendrils coiled, (7.5 - ) 12 - 14 x (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 in conspicuous, 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. Lid ovateelliptic (1 - ) 2.5 - 3.5 x (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 x 0.7 mm , apex rounded entire to 4-lacinate, inserted c. 4 mm below the peristome-lid junction. 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 x 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 x 1.5 mm; androphore c. 2 mm long; anther head 0.75 x 1.2 mm, anthers 5 - 8. Female inflorescences, infructescences and seed not seen. 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. 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. Pitcher exterior with sparse red-brown and branched white simple hairs, c. 0.1 x 0.1 mm extending to the lid (rarely glabrous) and marginal 0.1 - 0.2 mm and apex of the lower lid. Spur with hairs as the inflorescence. 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 x 0.05 mm. 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).A
Conservation
Assessed as Endangered (EN B2 ab(iii)) using the criteria of IUCN (2001).A
Distribution (General)
Peninsular ThailandA