| 1 | Leaves < 2.5 x 1 cm; inflorescences < 1 cm long, peduncle simple |
| 1' | Leaves > 2 x 1 cm; inflorescences > 2 cm long, peduncle with 1-3 pairs of basal cataphylls |
| 2 | Flowers 1-seriate |
| 2' | Flowers 2- or 3-seriate |
| 3 | Leaves linear to very narrowly lanceolate, with very acute apex; fruit ovoid, smooth when young |
| 3' | Leaves broadly obovate to elliptical, apex rounded; fruit globose, often warty when young or fresh |
| 4 | Flowers 2-seriate or mostly so |
| 4' | Flowers 3-seriate |
| 5 | Plants yellowish, percurrent, without intercalary cataphylls; inflorescences axillary only; leaves with rather obscure, palmate venation; Brazil nearly exclusively |
| 5' | Plants green, mostly dichotomous, the few percurrent shoots with intercalary cataphylls; terminal inflorescences present; venation completely obscure; known from Guyana only |
| 6 | Flowers yellow, contrasting with inflorescence axis; inflorescence peduncle ca. 1 cm long; percurrent shoots with 1-3 pairs of intercalary cataphylls |
| 6' | Flowers of same greenish color as inflorescence axis; inflorescence peduncle < 0.5 cm long; intercalary cataphylls absent |
