| 1 | Leaf blade (of adult or fertile shoots) simple, unlobed or lobed |
| 1' | Leaf blade (of adult or fertile shoots) foliolate |
| 2 | Dioecious(?). Plant tuberous. Inflorescences (infructescences) twice branched. Petals adaxially papillose. Filaments almost completely fused. Fruit glabrous. — Kangean Archipelago, Timor |
| 2' | Monoecious. Plant not tuberous(?). Inflorescences not or once-branched. Petals adaxially not papillose. Filaments connate in the lower half. Fruit glabrous or hairy |
| 3 | Plant, including fruit, densely soft-hairy, drying (dark) brown. — SE Papua New Guinea |
| 3' | Plant subglabrous or sparsely hairy, drying green. Fruit glabrous |
| 4 | Leaf blade 3-foliolate, petiole less than 0.5 cm long; leaflets carnose, wrinkled on drying, apex usually obtuse. Fruit 3-4 cm long. Seeds shortly 2-horned. — SE Continental Asia, East Malesia |
| 4' | Leaf blade 3- or 5-foliolate, petiole 0.5-3(-5) cm long; leaflets membranous, not wrinkled on drying, apex (obtuse or) acute. Fruit 2-8 cm long. Seeds star-shaped by coarsely 5-7 (double) dentate margin (edge) |
| 5 | Filaments partly united. Fruit c. 2 cm long. Stem towards base thorny. Leaflets without marginal glands. — East Malesia |
| 5' | Filaments free. Fruit 4-8 cm long. Stem not thorny. Leaflets often with glands on margin at base of lateral leaflets. — SE Continental Asia including South China through East Malesia to Australia and the Pacific |
