Nepenthes , popularly known as tropical pitcher plants or monkey cups, is a genus of carnivorous plants in the monotypic family Nepenthaceae. The genus comprises roughly 140 species, and numerous natural and many cultivated hybrids. They are mostly liana-forming plants of the Old World tropics, ranging from South China, Indonesia, Malaysia and the Philippines; westward to Madagascar [two species] and the Seychelles [one]; southward to Australia [three] and New Caledonia [one]; and northward to India [one] and Sri Lanka [one]. The greatest diversity occurs on Borneo and Sumatra, with many endemic species.
The name “monkey cups” refers to the fact that monkeys have been observed drinking rainwater from these plants.