Nepenthes hurrelliana

Appearance

Nepenthes hurrelliana is a climbing plant. Forms from different localities vary slightly in morphology. Plants from Mount Mulu and several other mountains have internodes up to 10 cm long.

The leaves of the type form from Mount Lumarku are up to 24 cm long and have a winged petiole, which clasps the stem for about half of its circumference and is decurrent for around 1 cm. Plants from Mount Mulu produce more narrowly lanceolate leaves with broadly winged petioles that are decurrent down the entire internode (≤10 cm long).

Rosette and lower pitchers are narrowly ovate to infundibular. They are large, growing to 30 cm in height. The lid or operculum is broadly triangular in shape and has an undulating margin. The peristome forms an extended neck (≤9 cm long) at the rear and is up to 7 cm wide at this point.

Upper pitchers are more infundibular than their lower counterparts, but also reach large dimensions of up to 28.5 cm. In aerial pitchers, the lid is much more narrowly triangular. It measures up to 8 cm long by 4.2 cm wide and has a cordate base. It bears a hook-shaped basal crest and a filiform apical appendage up to 5 mm long. A number of large, scattered nectar glands are present on the underside of the lid, particularly along the margins and near the base.

Nepenthes hurrelliana has a racemose inflorescence. Pedicels bear a basal bract measuring 3 to 4 mm in length.

The dense reddish-brown indumentum of N. hurrelliana is one of the most conspicuous of any Nepenthes species. The upper surface of the lid has rusty-brown hairs, while the lower surface only bears them along its margins. Unusually for Nepenthes, hairs are present even on the upper surface of the lamina and on the glandular crest of the lid.

Distribution

Nepenthes hurrelliana is endemic to Borneo, where it has been recorded from a number of mountains in northern Sarawak, southwestern Sabah, and Brunei. Specifically, it has been found on Mount Lumarku, Mount Mulu, Mount Murud, and mountains of the Meligan Range near Long Pasia (including Mount Rimau). It has a wide altitudinal distribution of 1300 to 2400 m above sea level. On Mount Murud (2423 m), N. hurrelliana is common on the summit ridge above 2100 m, but becomes rarer with increasing elevation as this brings with it more stunted and exposed vegetation. Populations from the summit ridge of Mount Lumarku (c. 1900 m) are extensive above 1620 m.

Habitat

The typical habitat of N. hurrelliana is tall mossy forest and upper montane forest, where it usually grows as an epiphyte up to 10 m off the ground. It has also been recorded from stunted mossy heath forest. Some plants occur terrestrially, although these are less common.

Nepenthes hurrelliana plays host to a number of pitcher infauna. One of the most conspicuous examples is a small golden-coloured frog of the genus Philautus, which has been observed in the pitchers of epiphytic N. hurrelliana on Mount Lumarku.