心果小扁豆 xin guo xiao bian dou

Heterosamara isocarpa (Chodat) Paiva.

Herbs annual, erect, 5-14 cm tall. Stems terete, ridged, glabrous; branches corymbose. Petiole ca. 5 mm, winged; leaf blade green, ovate or ovate-triangular, 1.5-2.5 × 0.6-1 cm, papery, both surfaces glabrous, or only abaxially sparsely setose, margin ciliate, midvein and lateral veins evident, base cuneate, decurrent, margin entire, apex acuminate. Racemes terminal, ca. 7 cm after anthesis; bracts and bracteoles caducous, ovate, shorter than flowers, apex acute. Sepals 5; outer sepals 3, one persistent after anthesis, broadly ovate, ca. 1 mm, apex acuminate; inner sepals 2, oblong or ovate, ca. 2 × 1.5 mm, 3-veined, base unguiculate, apex rounded. Petals 3, connate in lower 2/3, yellow; lateral petals obliquely oblong, ca. 2 mm, apex truncate, oblique, obtuse; keel shorter than lateral petals, cucullate, apex with 2-lamellate, obtriangular appendages, glabrous. Stamens 8; filaments ca. 1.5 mm, lower 2/3 united, forming an open staminal sheath, not ciliate; anthers basifixed. Ovary obovoid or subglobose, ca. 1 mm in diam.; style gradually broadening from base toward apex, curved, apex funnelform; stigma at lower margin. Capsule broadly obcordate or suborbicular, ca. 2 mm in diam., narrowly winged, wing with distinct transverse veins, adaxially flat, concave. Seeds black, shiny, ovoid, ca. 1 mm in diam., tuberculate, glabrous; strophiole white, 2-lobed, decurrent. Fl. and fr. Sep-Oct.

● On rocks in forests, grasslands, roadsides; 1200-1400 m. Guizhou, Sichuan (Yanbian), SE Yunnan.