紫水晶山蚂蝗 zi shui jing shan ma huang

Shrubs, to 2 m tall. Young branches angular, densely white or brown velutinous. Leaves 3-foliolate; petiole 1.5-5 cm; leaf­let blade ovate or elliptic, abaxially white or brown velutinous, adaxially velutinous then becoming sparsely so, base usually cuneately obtuse, margin entire, apex acute or mucronate, ter­minal leaflet 5-12 × 3.5-6.5 cm, lateral veins 8-10 on each side of midvein, reaching margin. Inflorescences 15-25 cm, termi­nal ones paniculate, axillary ones racemose, 2(or 3)-flowered at each node. Calyx 2.5-3 mm, 4-lobed. Corolla amethyst; stan­dard obovate, 8.5-10 mm, base cuneate, apex slightly emargi­nate; wings longer than keel petal, 10.5-11.5 mm, auriculate at lamina base; keel 8-10.5 mm, apex acute. Stamens 8.5-9 mm. Legume flat, linear, 18-28 × 4-7 mm, glabrous, upper suture nearly straight, lower suture indented, 6- or 7-jointed.

Mountain thickets; ca. 1800 m. Yunnan [Thailand].