Erect or ascending annual herb. Stem glabrous, not winged. Leaf paripinnately compound, leaflets 2, 2-9 cm long, 1-3 mm broad, linear or lanceolate, glabrous to subglabrous; stipules 3-15 mm long, semi-sagittate. Flowers solitary axillary, peduncle 1-15 mm. Calyx 5-6 mm long, teeth subequal, 1.5-2 times as long as the tube. Corolla red or orange. Vexillum 6-10 mm long. Fruit 3-6 cm long, 4-5 mm broad, linear-ensiform, glabrous, 5-14-seeded.