鞍叶羊蹄甲 an ye yang ti jia

Bauhinia altefissa H. Léveillé, p.p.; B. bonatiana Pam­panini; B. brachycarpa var. cavaleriei (H. Léveillé) T. C. Chen; B. brachycarpa var. densiflora (Franchet) K. Larsen & S. S. Larsen; B. brachycarpa var. microphylla (Oliver ex Craib) K. Larsen & S. S. Larsen; B. cavaleriei H. Léveillé; B. densiflora Franchet; B. enigmatica Prain; B. faberi Oliver; B. faberi var. megaphylla Tang & Wang; B. faberi var. microphylla Oliver ex Craib.

Shrubs, erect or spreading, or small trees, to 5 m tall, dioecious or androdioecious. Branches slender, puberulent when young, glabrous later. Stipules caducous, linear; petiole 1-6 cm; leaf blade suborbicular, 0.8-12 × 1-10 cm, papery or mem­branous, abaxially puberulent, adaxially glabrous or puberulent, primary veins 5-13, base truncate or shallowly cordate, apex bifid to ca. 1/2, lobes rounded at apex. Inflorescence a raceme, to 50-flowered, sometimes much condensed, terminal; bracts caducous, linear. Flower buds ellipsoid, puberulent. Hypan­thium turbinate, short. Calyx open as a spathe into 2 lobes. Petals white, obovate to oblanceolate, 7-8 mm, shortly clawed. Male flowers: fertile stamens 10 in 2 whorls; filaments 5-6 mm; reduced ovary small. Female flowers: reduced stamens 10; ovary hairy, shortly stalked; style stout; stigma peltate. Legume elliptic to oblanceolate, compressed, leathery, puberulent or nearly glabrous, dehiscent. Seeds 2-7, suborbicular, com­pressed. Fl. May-Jul, fr. Aug-Oct.

Open forests, dry mountain slopes; sea level to 3200 m. Chong­qing, Gansu, Guangxi, Guizhou, Hubei, Shaanxi, Sichuan, Xizang, Yun­nan [Laos, Myanmar, Thailand].

This is a polymorphic species, widely distributed in W China from Xishuangbanna in the south to Gansu in the north. At lower elevations and latitudes, as a small tree in open forests, its leaves can be much larger, but in habitats at higher elevations and latitudes, especially on slopes in dry river valleys, it is a small shrub no more than 30 cm tall, with leaves not exceeding 1 cm in diam.