Dioscorea platanifolia Prain & Burkill.

Rhizome horizontal, little branched, cylindric, 0.7--1.5 cm thick. Stem twining to left, sparsely hirsute, glabrescent. Leaves alternate, simple; petiole 5--12 cm; leaf blade drying greenish, orbicular to broadly ovate, usually 4--7-lobed or coarsely toothed, 10--17 × 10--13 cm, veins abaxially tomentose, basal veins 9 or 11, outermost ones sometimes pedately divided, base cordate with rounded sinus, margin undulate to distinctly coarsely toothed, apex acute to acuminate. Male spikes solitary or paired, sometimes branched, to 28 cm; axis puberulent. Male flowers: usually in lax cymules of 2--5; pedicel 2--3 mm; bract to 1 mm; bracteoles absent; perianth dull olive green, bowl-shaped, ca. 1.5 mm, lobes spreading; stamens 6, inserted at base of perianth, filaments incurved, short. Female spikes solitary or 2 or 3 together, 40- or more flowered. Female flowers: bracts lanceolate; staminodes filiform or absent. Capsule straw-colored, shiny, ca. 2.5 cm, base gradually narrowed, apex slightly widened; wings ca. 0.7 cm wide. Seeds inserted near base of capsule, ca. 8 mm; wing pointing toward capsule apex. Fl. Jun--Aug, fr. Jul--Sep.

Mixed forests, mountain slopes, ravines, roadsides; 1400--3200 m. Guizhou, Sichuan, E Xizang (Bomi Xian, Qamdo Xian), Yunnan [Thailand].