Nepenthes madagascariensis

Nepenthes madagascariensis

Synonymy

Nepenthes madagascariensis Poir., Encycl. 4(2): 459 (-460). 1798 sec. Jebb & Cheek 1997
    • =Nepenthes madagascariensis var. macrocarpa Scott Elliott, Ann. Bot. (Oxford) 5: 376. 1891 syn. sec. Jebb & Cheek 1997
      • Type: Scott-Elliott 2302, Madagascar, near Fort Dauphin
    • =Nepenthes madagascariensis var. cylindrica Dubard in Bull. Mus. Hist. Nat. 12: 63. 1906 syn. sec. Jebb & Cheek 1997
      • Type: Humblot 400 (P), Madagascar

    Description

    Terrestrially growing upright on a stem up to 1.5 m tall, or scrambling, or climbing vines up to 9 m long.
    The lamina is linear or elliptic, up to 28 cm long (rarely up to 40 cm) and 8 cm wide. 4-7 veins run parallel to the leaf margin. The apex of the leaf plate is acute or obtuse and the base is attenuate and petiolate. The petiole is winged up to 5 cm long (rarely up to 12 cm), and 1.5 cm wide. It clasps the stem, or is semi-amplexicaul, or slightly decurrent for one or two centimetres along the stem. The lamina is green, and the stem and midrib are light green or yellow. Lower pitchers are borne on green or reddish tendrils up to 38 cm long and 3 mm thick.
    The apex of the leaf is acute or obtuse and the base is attenuate and petiolate. The petiole is winged, up to 12 cm long, clasps the stem and may be slightly decurrent. The lamina is green, and the stem, midrib and tendril are light green or yellow. The stems may be covered with a very fine indumentum of short hairs.
    The stem and surface of the lamina are glabrous, the underside of the lamina, tendrils and immature upper pitchers are lined with light brown, unbranched, uniseriate (multicellular) hairs. This is especially obvious along the veins (also along the lateral veins of the lid). In older pitchers the upper side of the lid and the bottom two thirds of the pitcher are usually still covered with short (0.09 mm long) hairs that point upwards (towards the lid). All pitchers have a narrow zone just below the peristome with branched, arrested hairs 0.1-0.2 mm long. Similar hairs may be found along the periphery of the (otherwise glabrous) underside of the lid and have probably the function to seal the developing closed pitcher. Very dense red-brown indumentum is found on the younger parts of the inflorescence (pedicels, tepals, ovary), but the androphore of the male flower is completely glabrous.
    The lower pitchers are up to 14 cm tall and 5.5 cm wide. The bottom half of the trap is ovate and variably swollen. The pitcher narrows above this part, often forming a faint hip, and becomes cylindrical towards the pitcher opening. Wings up to 1 cm wide, fringed with filaments up to 5 mm long, run down the front of the pitcher. The wings are often incurved towards one another. The peristome is up to 6 mm wide and is lined with fine ribs up to 0.4 mm high, spaced up to 0.5 mm apart. A distinct gap of a few millimetres is usually present in the peristome below the lid. The peristome is of a consistent width around the margin of the pitcher opening, except for at the very back; here, on both sides of the gap, the peristome is expanded, forming two short triangular points up to 8 mm long. The lid is orbicular, elliptic or ovate, up to 5.5 cm long by 5 cm wide, and lacks appendages. The underside of the lid is scattered with a number of large, circular nectar glands up to 3 mm in diameter. These glands secrete nectar profusely. The spur is up to 6 mm long and is unbranched.
    The exterior of the lower pitcher is entirely reddish pink or reddish purple. The interior of pitcher is light pink to 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 wholly, narrowly infundibular, up to 18 cm tall (rarely up to 25 cm) and 7 cm wide. The bottom half of the pitcher is typically exceptionally narrow. The wings are reduced to narrow ridges, but may be hardly discernible at all. The peristome is up to 9 mm wide and lined with fine ribs up to 0.6 mm high, spaced up to 0.5 mm apart. As in the lower pitchers a distinct gap of several millimetres is usually present in the peristome, below the lid. The strongly developed peristome is of a consistent width around the margin of the pitcher opening, but expands on both sides of the gap to form two abruptly terminated triangular points up to 1.5 cm long. The lid is orbicular, elliptic or ovate, up to 7 cm long and 6 cm wide, and lacks appendages. The underside of the lid is lined with 100-200 (maximum 300) circular, nectar glands. Those near the centre are open and very large (up to 1.5 mm in diameter), and secrete nectar profusely. The gland size and density decreases towards the side of the lid, but around the outermost periphery, there are many small glands. The density of digestive glands on the interior of the pitcher is 240-400 cm2. The spur is up to 6 mm long and may be forked (Schmid-Hollinger, 1977) or unbranched (Stewart McPherson, pers. observ.).
    The upper pitchers are usually entirely bright yellow, but in some plants the lower surface of the lid may be bright red and the peristome flushed orange or red. The tendril of the upper pitchers usually coils to gain purchase on surrounding objects, and has the same yellow or green colouration as the pitchers.A

    Notes

    There are two species of Nepenthes in Madagascar. The second species, N. masoalensis, occurs immediately beyond the northernmost Iocality of the present species. Nepenthes madagascariensis is characterised by its wholly infundibuliform upper pitchers (vs. ventricose-tubular in N. masoalensis). Other differences are cited under N. masoalensis.B

    Distribution (General)

    Madagascar, east coast as far north as Masoala peninsula, commonest
    in south around Fort Dauphin.B

    Habitat

    Along the edges of swamps and in peaty /sandy soils; low altitudes. B

    Bibliography

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

    Specimens

    CountryDateCollector + collecting numberHerbariaTypeScanDerivatives
    Humblot 400 (P), Madagascar
    Citation: Humblot 400 (P), Madagascar

    Scott-Elliott 2302, Madagascar, near Fort Dauphin
    Citation: Scott-Elliott 2302, Madagascar, near Fort Dauphin