Tuesday, February 21, 2023

[Botany • 2023] Nepenthes berbulu (Nepenthaceae) • A Pitcher Plant from Peninsular Malaysia with remarkably long lid bristles


Nepenthes berbulu H.L.Tan, G.Lim, Mey, Golos, Wistuba, S.McPherson & A.S.Rob., 

in Tan, Lim, Mey, Golos, Wistuba, McPherson & Robinson, 2023. 

Abstract
A species of Nepenthes endemic to Peninsular Malaysia and distinctive for its extremely developed lid hairs is described and illustrated. Nepenthes berbulu is a highland species known only from a handful of peaks in the Titiwangsa Range. It is classified here within the recently defined N. macfarlanei group, for which a dichotomous key is provided. The description of this taxon brings the total number of Nepenthes species recognised from Peninsular Malaysia to eighteen.

Keywords: Nepenthes berbulu, Malesia, Nepenthaceae, new species, non-core Caryophyllales, taxonomy.

Nepenthes berbulu. A robust plant with particularly colourful upper pitchers growing among summit scrub at the type locality.
Photograph by F.S. Mey

Nepenthes berbulu. Intermediate pitcher at the type locality.
Photograph by F.S. Mey

Nepenthes berbulu. Lower pitchers borne on long tendrils among summit scrub at the type locality.
Photograph by F.S. Mey.

Nepenthes berbulu. Lower to intermediate pitchers at the type locality.
 Photograph by A. Wistuba.

Nepenthes berbulu H.L.Tan, G.Lim, Mey, Golos, Wistuba, S.McPherson & A.S.Rob.
 (a) Habit with upper pitchers and male inflorescence. (b) Close-up of upper pitcher showing lid underside and mouth. (c) Detail of thickened bristles near lid apex. (d) Rosette leaf with lower pitcher. (e) Upper surface of lower pitcher lid. (f) Lower surface of lower pitcher lid. (g) Detail of lower pitcher lid glands. (h) Peristome of lower pitcher in lateral aspect, showing pronounced column. (i) Spur. (j) Male flowers. (k) Female flowers. (l) Seedpod with dispersing seeds. Based on the type material (Lim 4) and photographs and measurements made in situ at the type locality.
Illustration by F.S. Mey.

Nepenthes berbulu H.L.Tan, G.Lim, Mey, Golos, Wistuba, S.McPherson & A.S.Rob., spec. nov.

Diagnosis: — Nepenthes berbulu differs from N. macfarlanei in having laminae of short and climbing stems that are oblong-elliptic with rounded-obtuse apices (vs. lanceolate with acute apices); lower pitchers that are broadly infundibular in lower half and cylindrical above a pronounced hip (vs. ovate in lower half and cylindrical above a faint hip); upper pitchers that are infundibular at the base and broadly cylindrical above a basally situated hip, with a flattened ventral surface between the wing vestiges (vs. wholly infundibular with a hip just below peristome or absent, and often slightly constricted below the mouth causing ventral gibbosity); and bristles on lower surface of lid aggregated towards lid apex (vs. evenly distributed).

Etymology: — The epithet berbulu is derived from the Malay prefix ber- (having) and the noun bulu (hairbristle), in reference to the basally fleshy bristles found on the lower surface of the pitcher lid.
 
Comparison grid of the six species of the Nepenthes macfarlanei group, showing lower pitchers, upper pitchers, and hairs under the lid:
 (A–C) N. berbulu, (D–F) N. macfarlanei, (G–I) N. alba,
(J–L) N. gracillima, (M–O) N. sericea, (P–R) N. ulukaliana.
Photographs by F.S. Mey (A–C, E–F, M–N, left, O–Q), M.R. Golos (D, R), S.R. McPherson (G, I, K), Chien C. Lee (H, J, L) & the late Christophe Maerten (N, right).

 
Hong L. Tan, Gideon Lim, François Sockhom Mey, Michal R. Golos, Andreas Wistuba, Stewart R. McPherson and Alastair S. Robinson. 2023. Nepenthes berbulu (Nepenthaceae), A Pitcher Plant from Peninsular Malaysia with remarkably long lid bristles. Carniv. Pl. Newslett. 52(1):15-43. DOI: 10.55360/cpn521.fm322