Rusjdi Tamin

Nepenthes rigidifolia is a critically endangered tropical pitcher plant endemic to Sumatra, where it grows at elevations of 1,000–1,600 m above sea level. The specific epithet rigidifolia is formed from the Latin words rigidus (rigid) and folia (leaves), and refers to the plant's stiff, coriaceous leaf blades. Tahul-tahul has been recorded as a local vernacular name for this species.

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.

Nepenthes izumiae is a tropical pitcher plant endemic to Sumatra, where it grows in montane forest at 1,700–1,900 m above sea level. It appears to be most closely related to N. lingulata and N. singalana. The specific epithet izumiae honours Izumi Davis, wife of Troy Davis, one of the describing authors.

Nepenthes adnata is a tropical pitcher plant endemic to the Indonesian province of West Sumatra, where it grows at elevations of 600 to 1200 m above sea level. The specific epithet adnata is Latin for "broadly attached" and refers to the base of the lamina.