Perennial evergreen vine, up to 10-20m long. Stems covered with leaf sheaths. Pinnate compound leaves alternate at the branch tips, sometimes nearly opposite on the lower parts; leaflets alternate, linear-lanceolate, about 20-30cm long and 3cm wide, apex sharply pointed, base narrow, with three parallel veins; petioles and rachis armed with sharp spines. Inflorescence a spadix, bearing pale yellow crown-shaped flowers, unisexual, dioecious; perianth of 6 segments arranged in two whorls; male flowers with 6 stamens, anthers long-conical; female flowers with 6 sterile stamens, one pistil, bottle-shaped, ovary slightly ovoid, densely covered with scales, style short, stigma deeply three-lobed. Fruit drupe-like, ovoid-spherical, about 2-3cm in diameter, reddish-brown, with yellow scales, containing deep crimson liquid resin inside the fruit, often exuding from under the scales, drying into blood-like clumps.