Description from Flora of China
Climbers dioecious. Stems prominently striated, with rather dense, thick hairs. Petiole 0.5-1.5 cm, densely pubescent; leaf blade ovate or long ovate, 7.5-13 × 4-8 cm, papery, abaxially sparsely appressed pubescent, adaxially pubescent along veins, especially at base, base rounded, symmetric or nearly so, apex shortly acuminate and obtuse; veins 7, apical pair arising 0.5-1.5 cm above base, others basal; reticulate veins prominent, finely glandular. Spikes leaf-opposed. Male spikes 7-14 cm, pendulous; peduncle slightly longer than petioles; bracts obovate, adnate to rachis. Stamens 2. Female spikes slightly longer than opposing leaf; peduncle longer than petioles, pubescent; rachis densely pubescent; bracts suboblong, base slightly tapered, adnate to rachis, 1.5-2 × ca. 1 mm, margin free. Ovary ovoid, distinct; stigmas 4 or 5, lanceolate. Unripe drupe ovoid, ca. 4 × 3 mm, Fl. May-Aug.
The Indian species Piper hookeri Miquel is closely related.
* Forests, on trees or rocks; 1100-1300 m. SE Yunnan (Xichou Xian, Maguan Xian, Pingbian Miaozu Zizhixian)