and cylindrical or tubulose above. Upper pitchers are produced on shorter tendrils, but are larger than their lower counterparts, growing to 25 cm in height and 4 cm in width. They have a pair of prominent ribs in place of wings, sometimes bearing fringe elements near the peristome. As in lower pitchers, the mouth is oblique, elevated, and acuminate towards the lid. The flattened peristome is up to 6 mm wide. It has a raised section at the front and is characteristically crumpled into 3 prominent folds. The glandular region covers the infundibulate part of the inner surface, with around 500 glands per square centimetre. The lid and spur are similar to those of lower pitchers. Nepenthes longifolia has a racemose inflorescence. Male and female inflorescences have the same structure. The peduncle is up to 25 cm long and 3 mm wide. The rachis is also up to 25 cm long. Partial peduncles are one- or two-flowered, up to 15 mm long, and may or may not be bracteolate. Sepals are ovate and up to 5 mm long. Stamens are approximately 5 mm long including the anthers. Seed capsules are up to 3 cm long. Most parts of the plant bear a short, sparse indumentum of simple and stellate hairs. However, many of these hairs are caducous and so mature plants appear mostly glabrous. The margins of the lamina are densely lined with short reddish-brown hairs. The stem and leaves are green, the latter sometimes having a reddish lower surface. Leaves of rosette plants often have a red midrib. Lower pitchers are generally brownish-red with a green to reddish-green peristome. The inner surface of the pitcher is usually pale green and the lid is red. Upper pitchers are characteristically light green throughout. Ecology Nepenthes longifolia occurs in the Indonesian province of West Sumatra and may also be present in North Sumatra. It grows terrestrially in dense, shady lowland or submontane forest on steep sandstone slopes and ridges. As a result of developing against such inclined surfaces, the leaves of rosette plants often assume an almost vertical orientation. The species has an altitudinal distribution of 300 to 1100 m above sea level. Around the river Tjampo in West Sumatra, N. longifolia is sympatric with N. adnata, N. albomarginata, N. ampullaria, N. eustachya, N. gracilis, and N. reinwardtiana. However, the species is only known to hybridise with N. eustachya. On Mount Tjampo