云开红豆 yun kai hong dou

Trichocyamos merrillianum (L. Chen) Yakovlev.

Trees evergreen, to 20 m. Stems with grayish brown bark and shallower longitudinal stripes; young branches fulvous tomentose. Leaves imparipinnate, 20-30 cm; stipule triangular, densely appressed fulvous velvety; petiole 4-5 cm; rachis 8-12 cm, not elongate at uppermost leaflet pair; leaflets 5-9; stipel lanceolate, densely appressed tomentose; petiolule thickened, 2-5 mm, densely appressed brown pubescent; blades elliptic-oblanceolate to oblanceolate, 5-20 × 3-7 cm, leathery, sparsely to densely gray to yellow-brown pubescent abaxially, glabrous and greenish adaxially, base cuneate to broadly acute, apex shortly acute to acuminate; lateral veins 12-17 pairs, raised on both surfaces, somewhat arcuate at margin. Panicles terminal, 17-30 cm, sparsely branched, slightly to densely patulous or appressed hairy; pedicel 2-5 mm; bracts deciduous. Calyx teeth triangular-oblong, ca. 4 × 3 mm, densely appressed rusty brown hairy. Corolla white; standard broadly ovate, ca. 1.2 × 1 cm including claw; wings broadly elliptic, ca. 9 × 6 mm, base 2-auriculate; keel ca. 7 × 4 mm, base shortly laterally 1-auricu­late, claw 4-5 mm. Stamens subequal; filaments glabrous, 6-12 mm. Ovary broadly ovate, sessile, densely appressed pilose; ovule 1; style filiform, 6-12 mm, base laterally pubescent. Leg­umes broadly ovate or obovate, turgid, 3.5-4.5 × 2.5-3.5 × ca. 1.5 cm, base rounded, apex obtuse or mucronate, stipe absent; valves densely appressed tomentose, internal septum absent. Seed 1, dark chestnut-brown or blackish, suborbicular or broadly obovate, slightly compressed, 1.5-2.4 × 1-1.5(-2.1) cm, glossy; testa densely concavely dotted; hilum small, ellip­tic, 1-1.5 mm. Fl. Jun, fr. Oct.

● Mountain slopes, valleys in open forests, forest margins; below 100-1200 m. Guangdong, Guangxi, Yunnan (Funing).