Medium-sized deciduous tree up to 10 m tall; bark deeply cracked, black with yellowish prickles usually straight; branchlets tomentose, armed; leaves 3-foliolate, up to 20 cm long; leaflets rhomboid-ovate, thin, coriaceous, base deltoid or truncate, apex acute, margins sinuate, lobed or entire, white-brown tomentose beneath, glabrous above; petiole up to 7 cm, petiolule about 1 cm; racemes short, densely capitates, about 8-10 cm; flowers 3.5 cm long, calyx campanulate, persistent, turbinate, not 2-lipped; corolla scarlet, exserted, very unequal, vexillary; standard 3-5 cm broad, wings shorter, keel petals connate, half as long as the standard; stamens diadelphous, upper stamen free, staminal sheath about 2 cm long, filaments unequal, alternating long and short; ovary oblong, pubescent, style incurved about 1cm; pods linear, scarcely torulose, spindle shaped; seeds 4-5.