Nepenthes pervillei

Nepenthes pervillei

Synonymy

Nepenthes pervillei Blume in Mus. Bot. Lugd.-Bat. 2: 10. 1852 sec. Jebb & Cheek 1997
  • Anurosperma pervillei (Blume) Hallier f. in Beih. Bot. Centralbl., Abt. 2, 39(2): 162, in obs. 1921 syn. sec. Jebb & Cheek 1997: urn:lsid:ipni.org:names:603643-1
    • Type (designated by Jebb, M.H.P. & Cheek, M.R. 19971): Seychelles, Mahé, Perville 98 (L).
  • 1. Jebb, M.H.P. & Cheek, M.R. 1997: A skeletal revision of Nepenthes. – Blumea 42(1): 1-106
  • =Nepenthes wardii E.P.Wright in Trans. Roy. Irish Acad. 24: 576, t. 29, 30. 1869 syn. sec. Jebb & Cheek 1997

Description

Stems climbing and scrambling, to 8 m long.
Juvenile plants form compact rosettes with many leaves that slowly increase in successive size, each with a very long lower-pitcher-bearing tendril. Maturing plants form stems up to 8 m long that climb and scramble trough surrounding vegetation, and bear leaves with coiling tendrils that fasten to surrounding objects (mainly branches) for support. The foliage of such stems rarely produce pitchers, but spaced along the lengthy internodes are compact aerial rosettes with sessile leaves. These rosettes bear distinct upper pitchers attached at the end of short and robust, bent (but never twining) tendrils. Some rosettes continue to grow and eventually form stems (causing the plant to branch), and repeated branching can cause established N. pervillei plants to cover the ground or the canopy with a dense carpet of pitchers. Sometimes differing pitcher colouration enables the observer to account masses of pitchers to just a few large plants growing next to each other.
The transition from juvenile plants with lower pitchers to adult plants forming climbing stems is abrupt, and rarely observed since pitchers of the climbing shoots are suppressed and so intermediate pitchers are generally not produced. Sometimes one or two greatly reduced, very small upper pitchers develop as a climbing stem is produced - these traps are similar to upper pitchers, but more slender and attached to twining tendrils.
The lamina is elliptic or oblong, up to 29 cm long and 6 cm wide. The apex of the leaf is rounded or obtuse and the base is attenuate, clasps the stem and may be slightly decurrent. The appressed blades of developing leaves simply open like a book to reveal the upper surface of the leaf, whereas in all other species of Nepenthes, the blades of developing leaves unfurl laterally, being initially curled in towards the midrib (Alastair Robinson, pers. comm.). The lamina has a very shiny surface and is dark or bright green. The stem may be yellow, green or (most usually) bright red. The midrib and tendril are yellow or orange. Most parts of the foliage appear predominantly glabrous, however, young and small (developing) pitchers, as well as the lower part of open traps and the part of the inflorescence may be lined with uniseriate hairs similar to those found on N. distillatoria and N. madagascariensis.
The lower pitchers are up to 12 cm tall and 4 cm wide. The bottom third to half of the pitcher is ovate and variably swollen, sometimes becoming almost spherical. The pitcher narrows above this part, often forming a faint hip, and becomes cylindrical or slightly infundibular towards the pitcher opening. Wings up to 8 mm wide, fringed with filaments up to 4 mm long, run down the front of the lower pitcher and are often positioned close to one another. The peristome is glossy, up to 6 mm wide, and is lined with fine ribs up to 1 mm high, spaced up to 0.5 mm apart. These ribs are often hardly discernible. There is often a gap of a few millimetres at the back of the peristome, below the lid. The lid is sub-orbicular, flat, up to 5.5 cm in diameter, lacks an appendage, and bears 30-100 nectar glands on the lower surface. The spur is up to 7 mm long and is usually forked.
The exterior of the lower pitcher is entirely reddish orange or reddish purple. The interior of the pitcher is light pink or almost white, and the peristome may be yellow, green, orange or red. Both sides of the lid are the same colour as the pitcher exterior.
The upper pitchers are borne on extremely short, rigid tendrils, often just a few centimetres long. The tendrils never coil or twine, but may be S-shaped. The pitcher opening of the upper traps always points away from the apical bud. Old pitchers usually turn downwards when dying (perhaps serving to release the nutrients and fluid in the traps into the soil). The dead upper pitchers are long lasting, and clothe the stem before detaching (Eric Schlosser, pers. comm.). The upper pitchers are up to 16 cm long and 4.5 cm wide. The bottom third to half of the pitcher is infundibular and variably inflated, and on the interior surface, is lined with digestive glands. Above this part, the width of the pitcher narrows (with a distinct hip) and becomes cylindrical or infundibular towards the pitcher opening. The relative proportions of the pitchers vary considerably between different plants and populations. Sometimes the upper, infundibular part of the pitcher is reduced to only one quarter of the length of the trap, whereas in other individuals it may be greatly lengthened. Usually the width of the pitcher narrows and is cylindrical immediately below the peristome. The peristome is up to 3 mm wide, and is lined with fine ribs up to 1 mm high, spaced up to 0.5 mm apart. Wings are consistently reduced to narrow ridges that run down the front of the trap or are not discernible at all. The lower surface of the lid is evenly lined with 100-200 nectar glands. Larger glands are found in the centre of the lid, but all glands are grown over by the epidermis leaving only a tiny exit hole for the nectar. The digestive glands at the bottom of the pitcher are located right next to the inner surface and their density is 400-600 cm². The density reduces higher up the pitcher, at which point they are almost covered.
The upper pitchers are usually coloured, and typically pure yellow or yellowish green, suffusing orange or reddish as they age. The lid may be the same colour as the pitcher, or its lower surface may be pure bright red.
The inflorescence is a loose panicle, 40 cm long, branches with up to 12 male or up to 5 female flowers. The peduncle is up to 18 cm long and up to 3.5 mm in diameter at the base, the rachis is up to 25 cm long. The tepals, which are fused at the base and occasionally number 3 instead of 4, are ovate with an acute apex and 3-4 mm long. The anther head is borne on a short column usually less than 2 mm long. The fruits are approximately 8-14 mm long and atypical of Nepenthes in that they are obconic (not attenuate towards both ends) and open with three valves (not four). The seeds are characteristically short, black in colour and ovoid or truncate in form. The distinctive seed of N. pervillei lack wings, are only 2-4 mm in length, and are carried poorly in the wind. This distinctive seed structure is a clear adaption towards inselberg habitat, as it reduces the likelihood that seed is blown far from the plants and lost at sea.A

Distribution (General)

Seychelles, Mahé and SilhouetteB

Etymology

The specific epithet honours French plant collector Auguste Pervillé who visited the Seychelles in 1841 and was among the first naturalists to make detailed observations of this plant.A

Habitat

Amidst dense but low growing scrub on granitic outcrops and hillsides, usually in strong or direct sunlight; 350 - 750 m a.s.l.A

Bibliography

A. McPherson, S. R. 2009: Pitcher Plants of the Old World 2
B. Jebb, M.H.P. & Cheek, M.R. 1997: A skeletal revision of Nepenthes. – Blumea 42(1): 1-106

Specimens

CountryDateCollector + collecting numberHerbariaTypeScanDerivatives
SeychellesPerville 98L
Citation: Seychelles, Mahé, Perville 98.

Specimen summary: L
Type for: Nepenthes pervillei Blume