| 1 | Petals pubescent on at least outer surface and margins; flowers mostly 5-merous; scales absent |
| 1' | Petals if present without hairs; flowers 4-merous; scales present (often inconspicuous) |
| 2 | Flowers 18-33 mm long, weakly zygomorphic; fruit 5-8 cm long |
| 2' | Flowers 3.2-4.4 mm long, actinomorphic; fruit 1-1.4 cm long |
| 3 | Stamens 4; petals absent |
| 3' | Stamens 8 or 10, rarely more; petals present |
| 4 | Flowers up to 5 mm long, not arranged in 'bottle-brush syndrome'; scales 40-60(-70) µm diam., marginal cells 8(-11) |
| 4' | Flowers at least 8 mm long, arranged in 'bottle-brush syndrome'; scales (50-)70-250 µm diam., marginal cells at least 15 |
| 5 | Leaves coriaceous, with usually only midvein prominent on lower surface or sometimes secondary veins also slightly so |
| 5' | Leaves chartaceous to subcoriaceous, with all veins from midvein to higher order venation at least slightly prominent on lower surface |
| 6 | Fruit 4-6.5 cm long, more than 4 x as long as wide |
| 6' | Fruit 1.4-4 cm long, less than 4 x as long as wide |
| 7 | Scales on leaves, flowers and fruit golden-yellow |
| 7' | At least most scales on leaves, flowers and fruit reddish |
| 8 | Flower buds more or less spherical, apex rounded; upper hypanthium (incl. calyx) distinctly less than 2 x as long as wide; fruit not much longer than wide |
| 8' | Flower buds elongated, apex acute to obtuse; upper hypanthium (incl. calyx) ca. 2 x as long as wide; fruit usually about 1.5 x as long as wide |
