Cleome aculeata L.

Erect, widely branched, annual herb, 0.25-0.5 m, rather densely covered with minute, glandular hairs, neither viscid nor smelling. Stem with fulvous, recurved, stipular thorns c. 1.5 mm. Leaves upwards gradually reduced in size, ultimately simple and subsessile. Leaflets 3, sub-sessile, thinly herbaceous, oblong, sometimes obovate, central leaflet c. 2.5-3(-3½) by 11.25-1.75(-2) cm; base acute to cuneate, slightly decurrent, top acute; nerves 5-8 pairs; petiole 2-3(-4½) cm. Racemes few-flowered, flowers subtended by simple, subsessile leaves. Pedicels 1.5-2 cm. Sepals linear, 1.5-2.25 by 0.25-0.5 cm, minutely glandular-hairy outside. Petals 1.75-4 mm (incl. claw 0.25-1 mm), obovate, pale yellowish. Stamens slightly exceeding the petals, anthers 1.5-1 mm. Ovary subsessile, cylindric, 2-3 mm long, glabrous. Fruit on a gynophore 0.5-2.5 mm, cylindric but abruptly tapering to both ends, 3.5-4 cm by 3 mm; valves finely parallel-nerved. Seeds asymmetrical, with closed cleft, 2-2.25 mm diam.; concentric ribs faint, obtuse, cross-ribs irregular, scattered, incomplete, distinctly prominent; elaiosome distinct.