小扁豆 xiao bian dou

Heterosamara tatarinowii (Regel) Paiva; Salomonia martini H. Léveillé; Semeiocardium hamiltonii Hasskarl.

Herbs annual, erect, 5-15 cm tall. Stems simple or much branched, longitudinally angular, glabrous. Petiole 5-10 mm, narrowly winged; leaf blade green, ovate or elliptic to broadly elliptic, 8-25 × 6-15 mm, papery, sparsely pubescent, penniveined, base cuneate, decurrent, margin entire, ciliate, apex acute. Racemes terminal, after anthesis to 6 cm; bracteoles 2, caducous, lanceolate, ca. 1 mm. Sepals 5, caducous after anthesis, green; outer sepals 3, ovate or elliptic, small, ca. 1 mm; inner sepals 2, petaloid, narrowly obovate, ca. 2 mm, apex retuse-rounded. Petals 3, connate in lower 2/3, red to purple-red; keel slightly shorter than lateral petals, tuberculate, apex rounded, without appendage. Stamens 8; filaments lower 3/4 united, forming an open staminal sheath; anthers ovoid. Ovary globose, ca. 0.5 mm in diam.; style curved, ca. 2 mm, apex funnelform, with oblique lobes; stigma on lower lobe. Capsule compressed-orbicular, ca. 2 mm in diam., sparsely pubescent, narrowly winged, apex mucronate. Seeds black, suboblong, ca. 1.5 mm, ca. 1 mm in diam., white pubescent; strophiole cucullate, small. Fl. Aug-Sep, fr. Sep-Nov.

Grasslands on slopes, thickets, roadsides ; (500-)1300-3000(-3900) m. Anhui, Fujian, Gansu, Guangdong, Guangxi, Guizhou, Hainan, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xinjiang, Xizang, Yunnan, Zhejiang [Bhutan, India, Japan, Kashmir, N Myanmar, Philippines; Malesia].