Danser's Monograph on Nepenthes: Nepenthes tentaculata

44. Nepenthes tentaculata HOOK. F., in D.C., Prodr., XVII, p. 101 (1873) ; BURB., Gard. Chron., 1882, 1, p. 56 (1882) ; BECC., Mal., III, p. 5 & 13 (1886) ; WUNSCHM., in ENGL. & PRANTL, Nat. Planzenfam., III, 2, p. 260 (1891) ; STAPF, Transact. Linn. Soc., ser. 2, bot., IV, p. 217 (1894) ; BECK, Wien. Ill. Gartenz., 1895, p. 188 (1895) ; BOERL., Handl., III, 1, p. 54 (1900) ; MACF., in ENGL., Pflanzenr., IV, 111, p. 42, ic. 15 (1908) ; Journ. Linn. Soc., XLII, bot., p. 125 (1914) ; MERR., Bibl. enum. Born., p. 285 (1921) ; END., Midd. O. Born. Exp. 1925, p. 277 (1927).

Icon: ENGL., Pflanzenr., IV, 111, p. 42 (1908) optima.

Folia mediocria sessilia, lamina elliptica ad lanceolata, nervis longitudinalibus utrinque 2-8, plerumque 4, basi profunde oblique amplicauli fere, in alas 2 decurrente ; ascidia rosularum ignota ; ascidia inferiora parva, ovato-conica, alis 2 fimbriatis, peristomio operculum versus acuminato, cylindrico, ad l l/2 mm lato, costis c. 1/2 mm distantibus v. indistinctis, dentibus 0 ; operculo ovato, facie exteriore plerumque appendicibus filiformibus, superea basi fascibus 2 filorum ramosorum, facie inferiore plana ; ascidia superiora magnitudine mediocria, subtubulosa, parte inferiore paulum dilatata, alis 2 fimbriatis raro costis 2 prominentibus ; peristomio operculum versus acuminato, cylindrico v. applanato, 1-5 mm lato, costis 1/2-1/3 mm distantibus, saepe indistinctis, dentibus 0 ; operculo ovato raro rotundato-elliptico, facie superiore plerumque appendicibus filiformibus, prope basim 2 fascibus filorum ramosorum, facie inferiore plana ; inflorescentia racemus parvus pedicellis plerumque 2-4, raro ad 15 mm longis, omnibus 1-floris ; indumentum in ascidiis iuvenilibus et in inflorescentiis parcum stellatum adpressum, ceterum 0.

Stems climbing, the part with adult leaves cylindrical or triangular, mostly 2 to 3, rarely up to 5 mm, thick, the internodes 1 to 10 cm long ; often short shoots at the base of older plants. Rosettes unknown. Leaves strongly varying in shape and dimensions, scattered, sessile ; lamina elliptic to lanceolate, usually 5 to 15 cm, rarely up to 20 cm, long, usually 1 to 3 1/2 cm, rarely up to 8 cm, broad, almost wholly amplexicaul, the base very oblique, almost decurrent, cordate ; pennate nerves more or less obliquely running towards the margin, irregularly reticulate, 2 to 8, usually 4, on each side, the longitudinal ones originating from the stem, running parallel in the outer 2/3 to 3/5 of the lamina ; tendrils of the lower leaves about as long as the leaf, hanging, without curl, those of the upper leaves about 1 1/2 times as long as the lamina, the pitcher bearing ones always with curl. Pitchers of the short shoots and lower ones of the longer stems ovate in the lower part, conical towards the mouth, very shortly incurved from the hanging tendril, up to 9 cm high, up to 4 cm wide, with 2 fringed wings over the whole length, the wings up to 4 mm broad, the fringe segments 1 to 1 l/2 times as long as the breadth of the wing, the segments 1/2 to 1 1/2 mm apart ; mouth very oblique, acuminate towards the lid, almost elongated into a short neck ; peristome usually cylindrical, rarely somewhat flattened, up to l l/2 mm broad, the ribs about 1/2 mm apart or indistinct, the inner margin entire, inner surface of the pitcher with not or little overarched glands in the lower 2/5 part ; lid ovate, obtuse, usually cuneate, rarely rounded at the base, mostly with filiform appendages on the upper surface up to 3 mm long and with a bundle of filiform appendages on each side of the spur, with a large number of small, not deepened and not rimmed glands on the lower surface ; spur not branched (not to be confounded with the bundles of appendages), flattened, up to 2 mm long. Pitchers of the climbing stems gradually originating from the hanging end of the tendril, the curve usually 2 to 8 mm wide, almost tubulose, 6 to 26 cm high, little ventricose in the lower part, 2 to 8 mm wide, 1 to 5 cm wide under the mouth, with 2 usually fringed wings over the whole length, the wings about 2 to 6 mm broad, the fringe segments once to twice as long as the breadth of the wing, the segments 1 to 6 mm apart, sometimes branched ; mouth oblique, ovate, acute or acuminate towards the lid or rarely elongated into a short neck ; peristome cylindrical or flattened, 1 to 5 mm broad, the ribs 1/2 to 1/3 mm apart or indistinct, the inner margin entire ; inner surface of the pitcher glandular in the ventricose part, the glands not overarched, about 300 to 400 on 1 cm2 ; lid ovate to oblong-ovate, rarely more round, obtuse or rather acute, cuneate at the base, with more or less numerous filiform appendages on the upper surface and a bundle of filiform appendages on each side of the spur, with numerous not rimmed glands on the lower surface ; spur not branched (not to be confounded with the bundles of threads), inserted, close to the lid, 3 to 15 mm long. Male inflorescence a small seemingly lateral raceme, the peduncle usually 2 to 3 cm long, usually 1/2 to 1, rarely up to 1 1/2 mm, thick, the axis usually 5 to 8, rarely up to 16 cm, long ; all pedicels 1-flowered, without bract, the lower ones usually 3 to 4 mm, rarely up to 15 mm, long, the upper ones little shorter. Tepals usually l 1/2 to 2 mm, rarely up to 3 mm, long, oblong to lanceolate. Staminal column usually about 2 mm, rarely up to 4 mm, long, the uniseriate anthers included. Female inflorescence in the main like the male one, shorter and looser, the pedicels longer, up to 10 mm. Tepals lanceolate. Ovary sessile. Fruit and seeds unknown. Indumentum only present in the very young pitchers and the inflorescences, appressed, stellate, the tepals only hairy along the margin, the ovary densely hairy. Colour of herbarium specimens fallow-dun or yellowish-brown to reddish, rarely blackish. (Description after all the specimens seen by the author.)

BORNEO. British North Borneo: without habitat: 900 m, 1853, LOBB, H. S. (0) ; I 1889, HAVILAND, H. S. (0) ; Mt. Kinabalu, Marai-parai spur, 22-23 XI 1915, CLEMENS 10883, H. B. (0) ; 2100 m, 1892, KALONG (HAVILAND) 1750, H. S. M. (0) ; 2400 m, 1892, HAVILAND 1660/1233, H. S. M. (m) ; Mt. Lobang, summit, 1500 m (Journ. Linn. Soc., XLII, p. 125) ; N.E. coast of Borneo (l.c.) ; Sarawak: G. Murud, summit, 2667 m, 6 XII 1914, MOULTON 192, H. S. (m) ; G. Rumput, 18 VIII 1912, ANDERSON 215, H. S. (m) ; 217, H. B. (m) ; G. Poi, IV 1913, MOULTON, H. S. (m) ; H. S. M. (m) ; VII 1908, H. S. M. (m) ; G. Matang, VII 1903, H. S. (f) ; VIII 1907, H. S. (m) ; 240 m, 18 VI 1893, H. S. M. (0) ; 900 m, 19 VII 1890, HULLETT, H. S. (0) ; G. Santubong, HEWITT, H. S. M. (0) ; Mt. Penrissen, 1200 m, from branch of a felled tree, V 1899, SHELFORD & FOX, H. S. M. (0) ; foot of Mt. Penrissen, 24 XI 1909, H. S. M. (0), Lingga, III 1913, H. S. M. (0) ; Mt. Tiang Laju, VI 1906, HEWITT 50, H. S. M. (m) ; Res. Western Division: G. Damoes, 22-24 X 1893, HALLIER B 606, H. B. (0) ; Amai Ambit, 15 IV-5 V 1894, HALLIER B 3389, H. B. (m) ; Res. Southern & Eastern Division: Bt. Raja, 2000 m, 6 X 1894, MOLENGRAAFF B 3466, H. B. (m) ; Bt. Batoe Tiban, 1700 m, X-XII 1925, MJÖBERG 49, H. B. (m) ; Bt. Batoe Ajoh, IV 1897, JAHERI (Exp. NEEUWENHUIS) 1651, H. B. (0) ; Bt. Batoe Lesoeng, 26 I 1899, AMDJAH (Exp. NIEUWENHUIS) 435, H. B. (0) ; 27 I 1899, idem 457, 460, 470, 471, 473, H. B. (0) ; 28 I 1899, idem 488 & 494, H. B. (0) ; Mt. Kemoel, 1500 m, 12 X 1925, ENDERT 3954, H. B. (m).

SELÉBÈS. Gov. Selébès and Dependencies: G. Sinadji, XI 1913, RACHMAT (Exp. VAN VUUREN) 900, H. B. (m).

N. tentaculata is more variable than most other species of its genus. Especially the dimensions of the inflorescences, flowers and pitchers vary greatly, in most cases the inflorescences and pitchers are smaller than those of any other Nepenthes, but now and then they are rather large. The relative length of the pedicels too is very different. Moreover sometimes the filiform appendages on both sides of the lid and on both sides of the spur and rarely also the fringe of the pitcher wings are absent, in specimens, which for the remainder are quite normal N. tentaculata. Now the var. imberbis of BECCARI (Mal., III, p. 13) differs, according to the author, "operculo supra nudo, calcare tentaculis parvis ornate". It is therefore probable, that BECCARI has not seen plants with fringeless wings, and it is difficult to say, whether the latter plants have to been reckoned to the var. imberbis, or not.

N. tentaculata is almost restricted to Borneo. The plant from Selébès has no appendages on the upper surface of the lid and on both sides of the spur, no fringe on the wings of the upper pitchers and, moreover it has a suborbicular lid and extremely long pedicels. So it differs enough to base a new species on it, but all its aberrant characters, except the form of the lid, are found now and then in specimens from Borneo. Further investigations have to decide, whether the plant from Selébès may be distinguished as a subspecies.

The var. tomentella of MACFARLANE (ENGL., Pflanzenr., IV, 111, p. 43) represents only an insignificant grade of hairiness.

Go to Next Page