Leaves petiolate; leaflets c. 13(28) × 11 mm, ovate or oblong, rounded or truncate at the apex, cuneate at the base, the lateral nerves 20–30 on each side; petioles mostly 3 cm long, reducing in the upper leaves; stipules with the free part longer than the base, tapering gradually.
Calyx sparsely pilose only at the margin; tube c. 2.5 mm long, strongly 10–11-nerved; teeth triangular with scarious margins at the base, subulate for three-quarters of their length, recurved in fruit.
Inflorescence terminal, ± globose, usually sessile in the axil of the uppermost pair of leaves; bracts up to 5 mm long, narrowly lanceolate, subulate at the tip or wholly subulate.
Corolla purple; standard oblong, rounded at the apex; wings with blade shorter than the claw, the auricle very short; keel with a white ventral nerve.
Pod oblong, with papery walls and thickened sutures, dehiscing dorsally, glabrous, 2-seeded.
Flowers with pedicels c. 1 mm long, not reflexed in fruit.
Ovary 1.5 mm long, 2-ovulate.
Annual herb, almost glabrous.
Stems prostrate or ascending.
Seeds yellowish-brown.
Stamens c. 5 mm long.