15. Senna bicapsularis (Linnaeus) Roxburgh, Fl. Ind., ed. 1832. 2: 342. 1832.
双荚决明 shuang jia jue ming
Cassia bicapsularis Linnaeus, Sp. Pl. 1: 376. 1753.
Shrubs, erect, to 3 m tall, much branched. Crown spreading, with pendent or sometimes climbing twigs. Leaves 7-12 cm, with 3 or 4 pairs of leaflets; stipules caducous, narrowly lanceolate, subulate, 1-3 mm; petiole 2.5-4 cm, slender; rachis with a blackish brown, clavate to ovoid gland between lowest pair of leaflets; leaflets obovate or obovate-oblong, 1.5-4 × 1-2.5 cm, membranous, glabrous, base obliquely cuneate, apex obtusely rounded. Racemes lax, in axils of apical leaves, 5-15 cm, slender; bracts early caducous. Sepals yellowish to reddish brown, ovate, 5-10 mm. Petals yellow, obovate, 1.1-1.5 cm, very shortly clawed. Stamens 10, 7 fertile: 3 lower with unequal filaments 2-10 mm, anthers large, curved, ca. 1 mm; 4 short with filaments ca. 1 mm and anthers 4-5 mm; 3 staminodes with minute anthers. Ovary with glabrous stalk and style. Legume brown, terete, straight or slightly curved, 9-17 × 1-1.5 cm, tardily dehiscent, valves membranous. Seeds 50-60, olive-green, ovoid, flattened, 5-7 mm.
Cultivated in Guangdong, Guangxi, Hainan [native to tropical America; widely cultivated in the tropics].