or branched and attains a length of 5 mm. Upper pitchers exhibit a similar pigmentation to lower pitchers, but are typically lighter. Nepenthes izumiae has a racemose inflorescence up to 18 cm long, of which the peduncle constitutes up to 10 cm and the rachis up to 8 cm. Flowers are borne solitarily on pedicels (≤5 mm long) that lack bracts. Tepals are ovate and up to 6 mm long. Fruits reach 15 mm in length. The structure of the male inflorescence has not been documented. An indumentum of red, brown or white hairs up to 1 mm long may be present on the laminar margins, pitchers (particularly lower ones), tendrils, and parts of the inflorescence. Ecology Nepenthes izumiae has only been recorded from two peaks north of Bukittinggi in the Barisan Mountains of West Sumatra, Indonesia. In the interests of conservation, the exact locality was not disclosed in the formal description. The species has an altitudinal range of 1700–1900 m above sea level. The typical habitat of N. izumiae is upper montane mossy forest, where conditions are moist and the plants experience diffused sunlight. At one location, the vegetation is dominated by ferns of the genera Dicranopteris and Dipteris. The species is most commonly epiphytic, often being found on moss-covered branches, but it can also grow terrestrially over a layer of moss. Nepenthes izumiae is naturally sympatric with N. dubia and N. gymnamphora, and a natural hybrid with the former has been recorded. The only known populations of N. izumiae lie outside the boundaries of national parks. Stewart McPherson considers the species to be "at significant risk of being poached and over collected" and cites the "rapid demise" of N. aristolochioides, another highly sought-after Sumatran plant, as an example of the possible fate of this species. Nepenthes izumiae is also threatened by forest and shrub fires as well as land development. Related species Nepenthes izumiae is thought to be most closely allied to two other Sumatran endemics: N. lingulata and N. singalana. With the former, N. izumiae shares the general morphology and colouration of its pitchers. However, it can be easily distinguished from that species as it lacks the highly developed filiform appendage that gives N. lingulata its name. It also differs in typically having an orbicular lid, as opposed to the triangular lid of N. lingulata, as well as broader pitchers with more highly developed peristome ribs and