Branches divaricate, rigid, sparsely leafy, glabrescent. All mature parts (except the corolla) sparsely and minutely strigillose. Leaves trifoliolate, (6-)12-25(-36) mm long; petiole ± half as long as the terminal leaflet; leaflets very narrowly elliptic to linear, (4-)10-20(-30) x (0.5-)l-2 mm, sparsely and inconspicuously strigillose on both surfaces. Stipules absent or when very rarely present then single at each node, linear, 1 mm long. Inflorescences leaf-opposed, distinctly pedunculate, umbellately (1-)3(-5)-flowered; peduncle short, (3-)5-10(-27) mm long; bracts minute, linear, ±0.5 mm long; bracteoles absent. Flowers 8-10 mm long, yellow; pedicel short, 1-1.5 mm long. Calyx subequally lobed but with the lower lobe narrower than the upper four, the sinuses of equal depth; lobes narrowly triangular, acute. Standard panduriform, as long as the keel; claw much dilated at the base, 2.5-3 x 1-1.5 mm at the base, with a small central callosity; lamina 5-7 x 4-5 mm, without lobes or callosities, glabrous but with a few minute hairs dorsally along the middle, often with a reddish brown line along the midrib. Wing petals oblong, slightly shorter than die keel, folded into a long shallow pocket near the base, glabrous; apex rounded; sculpturing indistinct or absent. Keel petals half oblong-elliptic, auriculate, glabrous; apex acute but not beaked. Androecium with the anthers markedly dimorphic; basifixed anthers linear, more than 2x longer than the small ovoid dorsifixed anthers; carinal anther intermediate in size and shape. Gynoecium subsessile; pistil ovoid-oblong, sparsely pubescent; style only slightly curved. Pods subsessile, shortly oblong, 10-14 x 2.5-3.5 mm compressed, glabrous, apex somewhat cuspidate, upper suture ± smooth, ±6-seeded, the seeds on 1.5-2 mm long funicles. Seeds subtriangular, ±1.5 mm in diameter; testa pale yellow, often with dark purple marks, densely but minutely tuberculate.
Robust annual, 0.3-0.6 m high; branches divaricate, sparsely leafy, glabrescent, mature parts sparsely strigillose. Leaves trifoliolate, 12-25 mm long. Leaflets narrowly elliptic to linear. Stipules absent. Inflorescences leaf-opposed, distinctly pedunculate, umbellate. Flowers yellow, pedicels short. Calyx subequally lobed, lower lobe narrower than upper four, sinuses of equal depth, lobes narrowly triangular. Petals: standard panduriform, often reddish brown along midrib; keel oblong-elliptic, auriculate. Pod shortly oblong, 6-seeded; seeds subtriangular.