Procumbent, annual herb; stems ± glabrous. Lvs almost glabrous or sparsely hairy on petiole and under surface of leaflets, glabrous above; petioles c. 10-60-(150) mm long; leaflets mostly obtriangular, obtuse to slightly emarginate or slightly acute, mucronate, obtuse to cuneate at base, serrate near apex, usually with dark markings, c. 5-20 mm long; terminal petiolule 2-4 mm long; lateral petiolules < 1 mm long; stipules ovate, acuminate, cordate, usually dentate, sometimes laciniate. Infl. 1-5-flowered; peduncles ± glabrous or sparsely hairy, < petioles; pedicels < or = calyx tube. Calyx sparsely hairy; calyx teeth narrowly triangular, = or > tube. Corolla yellow, 4-6 mm long. Pod ± glabrous, coiled in 3-7 turns without a hole in the centre, faintly reticulately veined and with a double row of spines at the margin, 3-7 mm diam. (excluding spines), few-seeded; seeds yellow to brown, c. 3 mm long.