Nepenthes lowii

Nepenthes lowii

Synonymy

Nepenthes lowii Hook.f. in Trans. Linn. Soc. London 22: 420, t. 71. 1859, sec. Cheek & Jebb 2001
    • Isotype: Borneo, Sabah, Kinabalu, H. Low s.n. (K).
    • Lectotype: Borneo, Sabah, Kinabalu, H. Low s.n. (K).

Other sources

Hooker, J.D. 1996 – In: Phillipps, A. & Lamb, A.L., Pitcher Plants of Borneo: 98, f. 53
Danser, B.H. 1928: – Bull. Jard. Bot. Buitenzorg, sér. 3, 9: 321
Clarke, C.M. 1997: Nepenthes of Borneo: 96, f. 64-66
Jebb, M.H.P. & Cheek, M.R. 1997: A skeletal revision of Nepenthes. – Blumea 42(1): 1-106: 55
Adam, J. H. & Wilcock, C.C. 1998: – Sarawak Mus. J. 50: 75-77: 154, f. XXIVb.
Kurata, S. 1976: Nepenthes of Mt Kinabalu, Sabah: 53
Phillipps, A. & Lamb, A.L. 1988: – Nature Malaysiana 13(4): 19, 20

Description

Terrestrial or epiphytic climber to 10 m tall. Stems terete or slightly ridged, 6-10 mm diam., internodes of climbing stems 3-7 cm long, axillary buds absent. Leaves coriaceous, petiolate; leaves of rosettes obovate, c. 7 by 4 cm, apex truncate to retuse, base cuneate; petiole to 2-3 cm long; leaves of short and climbing stems with blade narrowly oblong-lanceolate, 15-30 by 6-9 cm, apex rounded, base obtuse; petiole stout, canaliculate, 4-14 cm long, not auriculate, but slightly sheathed at the base, clasping the stem for 1/2-4/5 its circumference and sometimes with narrow, straight, decurrent ridges up to 10 mm long. Longitudinal nerves 2-4 on each side of the midrib in the outer 1/3, conspicuous. Pennate nerves inconspicuous. Lower pitchers rarely collected, subcylindrical, up to 13 by 4 cm, with two fringed wings in the upper 3/4, each 4-5 mm wide, fringed elements 3-5 mm long, 1-2 mm apart; mouth broadly ovate, oblique, concave, rising to the vertical near the lid to form a short column; peristome ± cylindrical, 2-3 mm wide, with well-defined ribs 1-1.5 mm apart, outer edge entire, inner edge long, flat, to 10 mm wide, with teeth 1-2 mm long; lid orbicular to ovate, c. 3.5 by 3.5 cm, lacking appendages, but with numerous patent, hair-like growths up to 10 mm long, nectar glands pit-like, c. 0.1 mm diam., situated at truncated ends of hair-like growths and on lid surface, often surrounded by dome-like, thick border c. 0.4 mm diam. Upper pitchers subwoody, 15-20(-28) cm high, the lower part globose or obliquely ovoid, 5-10 cm wide, held horizontally, with one side lowest, upper part curved upwards, then highly constricted before abruptly flaring out in the upper, infundibuliform part to about 6-12 cm wide at the mouth, wings reduced to ribs; mouth broadly ovate, oblique, straight; peristome reduced, detectable only as a line of corrugations 2 mm apart inside the rim; lid ovate-elliptic, 9-14 by 5.5-9 cm, apex rounded, base cordate, strongly keeled and vaulted and held erect, at c. 120° to the mouth, lower surface without appendages, but with numerous hair-like structures on the lower surface (see lower pitchers); spur unbranched, 14 mm long. Male inflorescence 15-37 cm long; peduncle 7-17 cm long, 0.3 cm diam. at base; partial peduncles 2-flowered, 0.5-4 mm long; bracts absent; pedicels 12-15 mm long; tepals elliptic, 4 by 3 mm; androphore 2-4 mm long; anther head 0.7-1.5 by 1.7-2 mm. Fruit valves 17-27 by 3-4 mm. Seed fusiform, 12-14 mm long, central part smooth. Indumentum: pubescent with short brown stellate hairs, rarely persisting on mature parts apart from lower midrib and edge of leaf blade. Colour of pitcher dark green outside, dark red inside; inflorescence dark red.A

Notes

Nepenthes lowii is distinguished from the similar N. ephippiata by its relatively smaller lid, with longer, slender bristles (6-7 by 0.5 mm tapering to a point) vs. the short, stout processes (3 by 2 mm tapering to a blunt 1 mm diam. apex) of the latter, and by its distinctive pitchers with their highly constricted waist, and the much reduced peristome which is still evident in the upper pitchers of N. ephippiata.
Nepenthes lowii is a singular species in the semi-woody, upper pitchers which have the lower part laterally reclined, lack a proper peristome and are extremely constricted at their midpoint. The lower pitchers are somewhat cylindrical and bear a well-developed peristome. The upper pitcher is green outside and a deep maroon red inside. The lid is relatively small, reflexed and has many long tapering bristles c. 6 mm in length. These bristles generate a white gelatinous exudate, although the composition and purpose is unknown (Phillipps, A. & A.L. Lamb Pitcher Plants of Borneo (1996) 98). Wistuba (1994) has suggested that the unusual pitcher shape may be an adaptation to prevent rainwater from diluting or leaching the pitcher contents below the narrow ‘waist’. Some collectors have remarked on the ability of these pitchers to trap leaf litter ‘a vegetarian pitcher plant’ (Ed de Vogel, pers. comm.). The tree shrew Tupaia montana has often been referred to by collectors as ‘licking’ the underside of the lids (presumably ingesting the white exudate), or ‘hunting for snails’ on the underside of the lids (Smythies in Symposium on Ecological Research in Humid Tropics Vegetation (1965) 170-178). Clarke in Nepenthes of Borneo (1997) 96 speculates that N. lowii may benefit from trapping tree shrew excrement as well as fallen leaves, and found animal excrement accounting for a large part of the pitcher detritus at five of the seven sites from which he studied pitchers of this species. Perhaps ingestion of the lid exudate prompts defecation in Tupaia! The species can be locally common in undisturbed areas but suffers greatly from curious humans (Phillipps & Lamb l.c. 1996).A

Distribution (General)

Borneo: Sabah (Mts Kinabalu, Trus Madi), Sarawak (Hose Mts, G. Buli, Tama Abu range, Bario, Mt Murud, Mt Mulu), Brunei, and Kalimantan.A

Habitat

Mossy forest, ridge tops on sandstone, granite, ultramafic or limestone; 1600-2600 m.A

Bibliography

A. Cheek, M.R. & Jebb, M.H.P. 2001: Flora Malesiana - Nepenthaceae, Series I, Volume 15

Specimens

CountryDateCollector + collecting numberHerbariaTypeScanDerivatives
Low, H. s.n.K(2)
Citation: Borneo, Sabah, Kinabalu, H. Low s.n.

Specimen summary: K
Isotype of Nepenthes lowii Hook.f.