This is a solitary rattan palm that produces a single, slender, spiny cane rather than a clump of multiple stems. Like many rattans, that cane eventually behaves as a climbing stem, using its elongated leaf structures and hooked armature to scramble through surrounding vegetation in the wet forests of southwestern Sri Lanka. The leaves are pinnate, with numerous narrow leaflets arranged along the rachis, and the sheaths are armed, giving the plant the heavily defended look typical of the genus Calamus. This species does not form a crownshaft, and its overall appearance is more that of a solitary climbing rattan than a trunked canopy palm. It is an endemic Sri Lankan species, known locally as Thundarena, and is associated with humid rainforest habitat, including areas such as Sinharaja.