Physostigma Balf.

Herbs or subshrubs, erect or climbing. Leaves pinnately 3-foliolate; stipules persistent, not spurred, ribbed; stipels persistent. Inflorescences either axillary on leafy stems or appearing terminal on leafless shoots, pseudoracemose, many-flowered; rhachis sometimes swollen at the insertion of the pedicels. Flowers mostly showy, white to purple. Calyx 5-lobed, 2-lipped, the lower 3 lobes ovate-triangular, the upper pair of lobes united to form an entire or bifid lip. Standard auriculate but without appendages, glabrous; keel with marked basal spur, apex beaked, spirally twisted. Vexillary stamen free; anthers 5 dorsifixed alternating with 5 basifixed. Ovary linear, 2–12-ovuled; style long, incurved for over 360°, narrowed below, thickened above, longitudinally barbate near the apex, furnished at the apex above the oblique stigma with a dorsal appendage. Pods linear or linear-oblong, often curved, the valves sometimes twisting after dehiscence. Seeds large or small, ellipsoid or subcylindrical; hilum linear or elliptic to ovate; aril absent.