Nepenthes jacquelineae is a tropical pitcher plant endemic to the Indonesian island of Sumatra. Due to its unique pitcher morphology, it is considered to be one of the most spectacular Nepenthes species native to the island. Botanical history Nepenthes jacquelineae was discovered in July 2000 by Charles Clarke and Troy Davis. The plants were found north of Bukittinggi, West Sumatra, growing at an elevation of around 1700 m. The formal description of N. jacquelineae was published in Clarke's 2001 monograph, Nepenthes of Sumatra and Peninsular Malaysia. Two collections of plant material were made on July 13, 2000. The herbarium specimen Clarke, Davis & Tamin 1307 was designated as the holotype of N. jacquelineae. It consists of two sheets from two different plants: a portion of a climbing stem with an upper pitcher and a mature female inflorescence; and an immature rosette with lower pitchers and a male inflorescence. The isotype Clarke, Davis & Tamin 1307, collected at the same time as the holotype, consists of a single sheet with a fragment of a sterile climbing stem bearing two upper pitchers. Both specimens are deposited at the Herbarium of Andalas University (ANDA). A third specimen, Nepenthes Team NP 384, is also deposited at the herbarium. The species is named after Charles Clarke's wife, Jacqueline Clarke. Description Nepenthes jacquelineae is a climbing plant. The stem, which is usually less than 5 mm thick, grows to 5 m in length and is cylindrical-angular in cross section. Internodes are up to 10 cm long. Leaves are sessile to sub-petiolate and have a coriaceous texture. The lamina is ovate-spathulate in form and grows to 20 cm in length and 6 cm in width. Three longitudinal veins are present on either side of the midrib together with numerous pinnate veins. Tendrils are up to 30 cm long. Rosette and lower pitchers are relatively small, rarely being more than 6 cm high and 4 cm wide. They are infundibular throughout and may or may not have fringed wings. They bear a wide, flattened peristome (≤10 mm wide) which is contracted in the middle. Ribs are barely discernible, except at the front of the peristome. Terrestrial pitchers have ovate lids. Small, circular nectar glands (≤0.5 mm wide) are concentrated on the underside of the lid near its apex. Several very large raised glands (≤1 mm wide) are also present. An unbranched spur (≤5 mm long) is inserted at