Pteroxygonum giraldii Damm. & Diels

Herbs perennial. Tuberoid nearly globose, large, to 15 cm in diam. Stems climbing, terete, more than 3 m, simple, striate, glabrous. Leaves petiolate, 2-4-clustered; petiole 3-7 cm, glabrous, usually curved near base; leaf blade triangular or triangular-ovate, 4-7 × 3-6 cm, abaxially sparsely pubescent along veins, adaxially glabrous, base broadly cordate or hastate, margin shortly ciliate, apex acuminate; ocrea 4-7 mm, membranous, glabrous but pubescent around base, apex acute, oblique. Inflorescence axillary, racemose, 2-5 cm; peduncle long, usually longer than leaves; bracts greenish, narrowly lanceolate, 4-6 mm. Pedicel 5-8 mm, articulate below middle. Perianth greenish or white; tepals elliptic, 3.5-4 mm. Stamens equaling perianth. Styles connate to below middle; stigmas capitate. Achenes much exceeding persistent perianth, black-brown, ovoid, ca. 1 cm, trigonous, winged along angles, 3-horned at base. Fl. Jun-Aug, fr. Jul-Sep.

Gansu, Hebei, Henan, Hubei, Shaanxi, Shanxi, Sichuan.

* Thickets in valleys, slopes; 600-2000 m.

Fagopyrum giraldii (Dammer & Diels) Haraldson.