Rootstock unknown. Stem twining to left, woolly. Leaves alternate, simple; petiole (2--)4--8 cm, hairy; leaf blade long cordate, 6.5--12 × 5--6(--12) cm, adaxially glabrous, smooth, abaxially hairy, basal veins 9 or 11, base deeply cordate with narrowly rounded sinus, apex acuminate or shortly caudate. Male thyrses often 2--4(or 5) together, 10--16(--20) cm, slender. Male flowers: in shortly pedunculate cymules of 2--5; bracts lanceolate; perianth lobes sometimes reddish brown spotted, ovate-triangular, abaxially sparsely hairy; stamens 6, filaments longer than anthers, anthers dorsifixed, introrse. Female spikes 17--25.5 cm, hairy. Female flowers: bracts lanceolate, apex acuminate; perianth lobes deltoid-ovate, ca. 1.8 mm; style enlarged basally, stigma 3-fid. Capsule reflexed, oblong, 2--3 cm, glabrous, base rounded, apex emarginate or truncate; wings 0.4--0.6 cm wide. Seeds inserted near base of capsule, wing pointing toward capsule apex. Fl. Jul--Aug, fr. Sep--Oct.

A collection from SW Yunnan (Cangyuan Va Zu Zizhixian), similar to Dioscorea martini but with unusually large fruits, was described as D. nanlaensis H. Li (Fl. Yunnan. 3: 739. 1983). Its status is uncertain and further collections are needed.

* Forest margins, valleys, river banks; 700--2400 m. Guizhou, Sichuan, Yunnan.