An annual, subwoody herb, 0.5—1 m tall, with many quadrangular, velvety hairy, yellow branches. Leaves simple, ovate to elliptical, 5—14 cm x 4—9 cm, pubescent; petiole 4—8 mm long; stipules sickle-shaped, 5—20 mm x 4—14 mm, auricled, persistent. Inflorescence a lax raceme, 5—25 cm long, leaf-opposed, with up to 24 flowers; pedicel filiform, up to 5 mm long; bracts linear-acuminate, 4 mm long; calyx campanulate, 7—11 mm long, hairy, with subequal triangular-acuminate lobes; corolla blue; standard elliptical to suborbicular, 14 mm in diameter; wings ovate-oblong, 13 mm x 6 mm; keel 12 mm x 6 mm, incurved in the middle. Pod oblongoid, 3—5 cm x 0.8—1.2 cm, short stalked, about 16-seeded. Seed heart-shaped, 3 mm in diameter, blackish. |