| 1 | Twigs nearly always more than 3 mm in diam. Leaves (2- or) 3-4-jugate |
| 1' | Twigs rarely more than 3 mm in diam. Leaves 1- or 2- (exceptionally 3-)jugate or sometimes 1-foliolate. Philippines |
| 2 | Petals absent or sometimes 1 rudimentary one present. Filaments glabrous. Borneo |
| 2' | Petals 4, rudimentary. Filaments with some long hairs in the basal half. Sumatra, Java |
