Nepenthes lavicola

Nepenthes lavicola

Synonymy

Nepenthes lavicola Wistuba & Rischer in Carniv. Pl. Newslett. 25(4): 106 (-111, fig. 1-5). 1996 sec. Cheek & Jebb 2001
    • Holotype: Sumatra, Aceh, G. Telong, alt. 2000 m, 26 Mar 1996, A. Wistuba & H. Rischer 26032 (L)

Description

Terrestrial climber to 3 m tall. Stems of short shoots terete, 5 mm diam., internodes c. 5 mm long; climbing shoots terete with a groove beginning in each axil spreading to give a flattened side and so stem in part obscurely triangular, 4-7 mm diam., internodes 4-8 cm long, axillary buds inconspicuous. Leaves coriaceous, sessile or obscurely petiolate; short shoot leaves oblanceolate to oblanceolate-spathulate, 6.5-11.5 by 2-2.8 cm, apex acute to obtuse, base attenuate, clasping the stem for 1/2-2/3 its circumference and decurrent as wings for c. 3 mm; leaves of climbing stems narrowly oblong, rarely subpetiolate, 11-17 by 2-3.2 cm, apex obtuse, not peltate, base clasping the stem for 1/2-2/3 its circumference, decurrent and slightly amplexicaul as a straight wing c. 5 mm wide, 6-15 mm below the axil. Longitudinal nerves 4 or 5 (2 in the short-stem leaves) on each side of the midrib in the outer 1/2, inconspicuous. Pennate nerves oblique, inconspicuous. Lower pitchers broadly ovoid to globose, with a short subcylindrical apex, 4.5-6.5 by 3.5-4.2 cm, with two fringed wings 1.5-4 mm wide, fringed elements 3-5.5 mm long, 1.5-3 mm apart; mouth highly concave, horizontal at the front rising to the vertical, or overarching, at the rear; peristome subcylindrical, 3 mm wide, ribs 0.5 mm apart, 0.2 mm high, with intermediate striae, outer edge entire, inner edge with teeth c. 0.5 mm long, conspicuous only at the rear; lid orbicular, 2-2.2 by 2-2.1 cm, apex rounded, base cordate, lower surface lacking appendages, nectar glands 15-50 scattered along the midline, circular, narrowly bordered, 0.3-0.5 mm diam.; spur 3-5 mm long, tapering to a point, entire or forked within 1 mm of the apex. Upper pitchers narrowly infundibuliform or slightly ventricose in the lower half and cylindrical above (9-)12.5-15.5 by 3-3.4 cm, lacking fringed wings but with two ridges; mouth ovate, concave, oblique, rising from near horizontal to near vertical at the rear, peristome as in the lower pitcher, but slightly flattened and up to 8 mm wide in the rear half, c. 2 mm wide in the front; lid ovate, 3.2-3.8 by 2.4-2.9 cm, apex rounded, base cordate, lower surface lacking appendage or keel, nectar glands circular, narrowly bordered, c. 0.3 mm diam. in the centre, 0.2 mm diam. towards the margin, along the midline longitudinally elliptic, 0.4 mm long; spur tapered to a point, 5 by 0.75 mm, entire. Male inflorescence c. 38 by c. 3 cm; peduncle 18 cm long, 3 mm diam. at base; partial peduncles c. 60, 2-flowered (1-flowered towards the apex of the rhachis), 0-4 mm long; bract inserted near the base of the partial peduncle or on the rhachis adjoining, attenuate, 6-8 by 0.5 mm, apex acute; pedicels 5-8 mm long; tepals 4-5 by 2-2.5 mm; androphore (2-)3.5-4 mm long; anther head 1.5 by 1.75-2 mm. Infructescence 26.5 by 5.5 cm; peduncle erect, 19.5 cm long, c. 5 mm diam. at base; partial peduncles up to 40, 2-fruited; bracts 16-18 mm long. Fruits with valves 17-20 by 2-4 mm. Seeds filiform, 7 by 0.2 mm. Indumentum of sessile red glands c. 0.1 mm diam. on stems, upper and lower leaf surfaces and on pitchers; pale to mid-brown simple or sparsely branched hairs 0.2-0.3 mm long in patches in the axils of the youngest leaves and in the stem grooves, hairs of this type also sparsely and inconspicuously scattered along the upper and lower leaf midrib, and scattered over the pitcher and upper lid including the spur where they are fine, greyer and arachnoid and mixed with minute white stellate hairs; inflorescence velvety with dull, pale brown patent hairs 0.1-0.3 mm long, present from peduncle base to lower tepals; androphore with scattered dull red-brown semi-patent hairs 0.3-0.5 mm long on the lower 2/3. Colour of pitchers dark brownish purple to almost black, rarely yellowish green with black spots, peristome yellowish green, sometimes with red stripes, mouth pale green in upper pitchers, spotted red in lower pitchers. Flower colour unknown.A

Notes

Nepenthes lavicola seems most closely related to N. spectabilis in its elongated, slightly infundibuliform upper pitchers, in the ovate lid, in the similar nectar gland shape and distribution and in the stem and leaf morphology. However, N. lavicola has shorter upper pitchers with a mainly rounded, narrower (not flattened, broader) peristome which has more prominent ribs than in N. spectabilis, and in all these characters approaches N. singalana. Nepenthes lavicola is distinguished from N. spectabilis in being distinctly less hairy, in the short (3-5 mm rather than 10-22 mm long), pointed, sometimes bifurcate spur, in the shorter fruit valves (17-20 mm not c. 40 mm) and in the tendency to longer bracts (16-18 mm long in the female of N. lavicola).
Nepenthes lavicola together with N. mikei (the latter collected by Frey-Wyssling in the same area in 1930) are the most northerly, by about 120 km, of all Sumatran Nepenthes. Nepenthes lavicola is the only species of the genus recorded from lava. It is known to us only from the specimens cited, all gathered in a few adjoining hectares. Wistuba & Rischer suggest in their protologue (cited above) that it is likely to be found elsewhere on the G. Geuredong massif, e.g. also on G. Geuredong and G. Popandji.A

Distribution (General)

Sumatra: C AcehA

Habitat

Open slopes on old lava flow dating from 1856; 2000-2600 m.A

Bibliography

A. Cheek, M. R. & Jebb, M. H. P. 2001: Flora Malesiana - Nepenthaceae, Series I, Volume 15. – Leiden: Nationaal Herbarium Nederland, Universiteit Leiden branch

Images

Specimens

CountryDateCollector + collecting numberHerbariaTypeScanDerivatives
1996-03-26Wistuba, A. & Rischer, H. 26032L
Citation: Sumatra, Aceh, G. Telong, alt. 2000 m, 26 Mar 1996, A. Wistuba & H. Rischer 26032

Specimen summary: L
Holotype of Nepenthes lavicola Wistuba & Rischer