Flask-shaped Pitcher Plant

Nepenthes ampullaria is one of the most widespread tropical pitcher plants, found from Thailand and Sumatra to Borneo and New Guinea. It carpets the forest floor with small, round, flask-shaped pitchers and gets much of its nitrogen from fallen leaves as well as from insects.

Nepenthes ampullaria is hard to confuse with any other species. Its light brown stem may climb to 15 m (49 ft), with light green leaves up to 25 cm long and 6 cm wide. The characteristic pitchers, however, are mostly borne in numerous rosettes sunken in the leaf litter or moss of the forest floor, on tendrils no more than 15 cm long. The tall climbing stems usually lack upper pitchers; the few upper pitchers ever recorded are tiny and very uncommon.

The pitchers are urceolate (pot-bellied), rarely more than 10 cm (4 in) tall and 7 cm wide, with a strongly incurved peristome and a pair of fringed wings at the front. The lid is small, narrow and bent back, away from the mouth. Colour ranges from light green throughout to entirely dark red, with many intermediates. Plants from Sumatra and Peninsular Malaysia are almost always green or green with red speckles, while red forms are mostly confined to Borneo; a large-pitchered form is known from New Guinea. The eastern (New Guinea) and western populations are otherwise indistinguishable. Young parts of the plant are densely covered with short brown hairs.

The inflorescence is a dense panicle, unusual in the genus. The species flowers once or twice a year for several weeks, often at the same time as its neighbours, and so it forms natural hybrids readily, including N. × hookeriana (with N. rafflesiana) and N. × trichocarpa (with N. gracilis).

Oprindelig region: Borneo, Sumatra, Peninsular Malaysia, Singapore, Thailand, the Maluku Islands and New Guinea

Klimazoner: Tropical lowland, mostly below 200 m (rarely to 2,100 m)

Nepenthes ampullaria grows in damp, shady forest. In Borneo it occurs on fairly flat ground in kerangas (heath) forest, peat swamp forest and degraded swamp forest; in Sumatra and Peninsular Malaysia it also grows in padang, belukar and even paddy fields; in New Guinea it is found mainly in Araucaria forest. It has also been recorded from secondary forest, open low vegetation and swamp grassland. Cheek and Jebb give its range as sea level to 200 m, rarely up to 2,100 m (6,900 ft).

Moden størrelse: Stems climb to 15 m; pitchers rarely over 10 cm (4 in) tall

Vækstrate: Moderate

Fældetype: Pitfall Trap

Nepenthes ampullaria has largely moved away from hunting and is partly a detritivore: its ground-level pitchers collect and digest leaf litter falling from the canopy. Its traps show several adaptations to this. The lid is very small and bent outwards, so it does not shield the mouth and leaves can drop straight in. Nectar glands on the lid are rare or absent, the glands of the peristome are reduced, and the digestive zone reaches almost to the rim, leaving little or none of the slippery waxy zone that other species use to make insects fall. It is also one of the few species without 'lunate' cells, which are thought to deny prey a foothold.

The pitchers are long-lived, because the plant relies on a slow build-up of nutrients. Organisms living in the fluid, such as mosquito larvae, are thought to help break down the litter and release ammonium the plant can absorb. A 2011 study found that plants obtained about 42% of the nitrogen in their leaf blades and about 55% of that in their pitchers from leaf litter.

The name comes from Latin ampulla, a flask.
At least 59 species of animals have been recorded living in its pitchers, including Microhyla nepenthicola, one of the smallest Old World frogs.
Under the forest canopy, plants have been estimated to take about a third or more of their leaf nitrogen from fallen leaves.
Its pitchers often cover the ground like a carpet, intercepting as much falling debris as possible.
The cultivar 'Cantley's Red' is a particularly attractive red form.
The IUCN Red List assessed the species as Least Concern in 2018 (Clarke, assessment T39640A143958546).

The species was described by William Jack, and its lectotype is a Jack specimen from Singapore. The name appeared posthumously in the Companion to the Botanical Magazine in 1835. Many varieties were named in the 19th and early 20th centuries, mostly for garden colour forms; B. H. Danser considered them unimportant, and the most recent, var. racemosa from Sarawak, dates from 1990.

In an account published in 1932, the botanist Troll described meeting the plant in a swamp forest on Siberut, off western Sumatra: pitchers gleamed through the lianas and the mossy ground was so covered in them that it looked like a carpet. In the 1996 book Pitcher-Plants of Borneo it was given the English name flask-shaped pitcher-plant.

1. Nepenthes ampullaria, Wikipedia
2. Nepenthes ampullaria, Caryophyllales Network: Nepenthaceae (after Cheek & Jebb 2001, Flora Malesiana I, 15)
3. Nepenthes: species of Borneo, The Carnivorous Plant FAQ (Barry Rice)
4. Nepenthes: basic cultivation, The Carnivorous Plant FAQ (Barry Rice)
5. Nepenthes: advanced cultivation, The Carnivorous Plant FAQ (Barry Rice)
6. Thumbnail guidelines on growing a tropical pitcher plant, The Carnivorous Plant FAQ (Barry Rice)