Dioscorea subcalva Prain & Burkill

Tubers vertical, cylindric; transverse section white; roots fibrous. Stem twining to left, woolly, glabrescent. Leaves alternate, simple; petiole 3--5(--8) cm; leaf blade orbicular- or ovate-cordate, 4.5--11 × 4--13.5 cm, adaxially glabrous, abaxially sparsely woolly, sparsely pubescent, or glabrous, basal veins 7 or 9, base cordate with narrow sinus, apex acuminate or caudate. Male thyrses usually 2 or 3 together, 3--12 cm, sparsely pubescent or glabrous. Male flowers: in pedunculate cymules of 2--6; bract solitary, brown-red dotted, triangular-ovate or ovate, 1.5--2 mm, base clasping, apex acute; perianth lobes lanceolate, ca. 2.2 mm; stamens 6, filaments equaling or slightly longer than anthers, anthers dorsifixed, introrse. Female spikes 3--14 cm. Female flowers: bracts triangular-lanceolate, brown-red dotted, perianth lobes narrowly ovate or oblong, ca. 2 mm, apex slightly obtuse; style slightly enlarged basally, stigma 3-fid. Capsule reflexed or spreading, 1.5--3 cm, glabrous, smooth; wings 0.5--0.8 cm wide, sometimes slightly undulate. Seeds inserted near base of capsule; wing pointing toward capsule apex. Fl. Jul--Aug. fr. Sep--Oct.

Guangxi, Guizhou, Hunan, Sichuan, Yunnan.

* Scrub forests, forest margins, mountain valleys, slopes; 700--2600 m.