Crotalaria nigricans Baker

Perennial, with erect or prostrate stems, up to 7(–15) dm. long.. Stem much branched, with rather sparse fine spreading hairs; plants often drying blackish.. Leaves shortly petiolate, 3-foliolate; leaflets oblanceolate to obovate-oblong, up to 15–28 mm. long, 5–12 mm. wide, sparsely pubescent or rarely glabrous above, thinly pubescent beneath; petiole up to 2–6 mm. long.. Stipules lanceolate, up to 3–6 mm. long.. Flowers ± 4–12, in sessile or shortly pedunculate dense heads up to 2·5 cm. long; bracts ovate, up to 5(–9) mm. long, acuminate; bracteoles inserted just below the calyx, similar to the bract, but slightly smaller.. Calyx 4-lobed, almost enclosing the petals, slightly accrescent, 8–13 mm. long, pubescent; lobes ovate, 2–3 times as long as the tube.. Standard orbicular-obovate to oblate, usually pale yellow, slightly reddish tinged and puberulous along the midvein towards the apex outside; wings longer than the keel; keel rounded about the middle, with a short incurved untwisted beak, up to 8–10 mm. long.. Pod sessile, ellipsoid, 7–10 mm. long, enclosed by the accrescent calyx, spreading pubescent outside, sparsely hairy inside, ± 4–7-seeded.. Seeds oblique-cordiform, ± 2·5 mm. long, smooth, mauvish-brown.