落葵薯 luo kui shu

Boussingaultia cordifolia Tenore in Ann. Sci. Nat., Bot. sér. 3, 19: 355. 1853; B. gracilis Miers; B. gracilis f. pseudobaselloides Hauman; B. gracilis var. pseudobaselloides (Hauman) Bailey.

Vines twining, with thick, hardy rhizome. Leaves shortly petiolate; leaf blade ovate to subcordate, 2-6 × 0.5-5.5 cm, thinly fleshy, base rounded or cordate, apex acute, producing small axillary tubercles (bulbils). Racemes many flowered; rachis pendent, thin, 7-25 cm. Bracts not longer than pedicel, narrow, persistent. Pedicel 2-3 mm, receptacular tip cupular, flowers shed from here. Lower bracteoles broadly triangular, hyaline, apex acute, persistent; upper bracteoles greenish white, flattened, orbicular to broadly elliptic, shorter than perianth. Flowers ca. 5 mm in diam., fragrant. Perianth white, inflexed, patent in anthesis; segments ovate or oblong to elliptic, 3 × 2 mm, apex blunt. Stamens white; filaments reflexed at apex in bud, spreading in anthesis. Style white, split to 3 stigmatic arms, each with 1 club-shaped or broadly elliptic stigma. Utricle and seed not seen. Fl. Jun-Oct.

Cultivated. Beijing, Fujian, Guangdong, Hainan, Jiangsu, Sichuan, Yunnan, Zhejiang [native to South America].

The plants are not known to produce seeds, but are propagated vegetatively by the axillary bulbils. The bulbils, leaves, and roots are used medicinally.