Which Nepenthes species is known only from Mount Kelam's granite cliff faces?

Nepenthes clipeata is the Nepenthes species known only from Mount Kelam’s granite cliff faces.

This tropical pitcher plant is endemic to Mount Kelam in West Kalimantan, Indonesian Borneo, where it grows on near-vertical granite walls at roughly 600–800 metres. Its habitat is unusually exposed and difficult to reach, helping explain why the species has such a restricted range.

The species was first collected in 1894 by German botanist Johannes Gottfried Hallier, who climbed Mount Kelam five times during that expedition. Its name, clipeata, comes from the Latin clipeus, meaning “round shield,” a reference to its distinctive, nearly circular leaves. The leaves are peltate: the tendril attaches to the underside of the leaf blade before the tip.

A common mix-up is with Nepenthes rigidifolia, N. khasiana, and N. aristolochioides, all of which are also rare pitcher plants but have different distributions. N. clipeata is especially notable for its conservation history: overcollection, drought, fires, and habitat pressure have made it one of the most threatened Nepenthes species.