5. Canavalia rosea (Swartz) Candolle, Prodr. 2: 404. 1825.
海刀豆 hai dao dou
Dolichos roseus Swartz, Prodr. 105. 1788; Canavalia maritima Thouars; C. obcordata (Roxburgh) Voigt; C. obtusifolia (Lamarck) Candolle; D. maritimus Aublet; D. obcordatus Roxburgh; D. obtusifolius Lamarck.
Herbs, robust, twining. Stems sparsely puberulent. Leaflets obovate, ovate, elliptic, or suborbicular, 5-8(-14) × 4.5-6.5(-10) cm, pilose on both surfaces, base cuneate to rounded, apex rounded, truncate, emarginate, or mucronate. Racemes axillary, to 30 cm including peduncle. Flowers 1-3 clustered at each node. Calyx 1-1.2 cm, pubescent, upper lip semiorbicular, 3-4 mm. Corolla purple; standard orbicular, ca. 2.5 cm, apex emarginate; wings falcate, auriculate; keel oblong, curved, auriculate. Legumes linear-oblong, 8-12 × 2-2.5 cm, apex rostrate, each valve with extra rib ca. 3 mm from sutural rib. Seeds brown, elliptic, 13-15 × ca. 10 mm; hilum ca. 10 mm. Fl. Jun-Jul.
Sandy beaches. Fujian, Guangdong, Guangxi, Hainan, Taiwan, Zhejiang [tropical coastal areas].
For the nomenclature of Canavalia rosea, see Aymard in Ernstia (8: 19-25. 1998).