SHORT KEY

1Leaves: biternate
1'Leaves: bipinnate
1''Leaves: simple, unifoliolate, imparipinnate, digitate
1'''Leaves: paripinnate
2Fruit: with stinging hairs (Fig. 1a)
2'Fruit: winged, with apical crest, or small sharp margin along lobes (Fig. 2)
2''Fruit: warty, densely spiny, or densely scaled (Fig. 1b-j)
2'''Fruit: smooth or wrinkled, no stinging hairs, no wings
3Seed: naked, placenta not thickened
3'Seed: with arillode and/or sarcotesta or placenta thickened
4Indumentum: stellate or hairs in bundles, also simple hairs
4'Indumentum: only simple hairs or glabrous
5Pseudo-stipules: present
5'Pseudo-stipules: absent
6Wall of fruit inside: pilose, sometimes margin of valves only
6'Wall of fruit inside: glabrous