| 1 | Inflorescences composed of umbelliform cymes. |
| 1' | Inflorescences composed of peduncled, disciform capitula. |
| 2 | Inflorescences verruculose. Leaf-margin with wide, shallow crenations; petiole inserted 2-3 mm from base |
| 2' | Inflorescences glabrous, papillose or puberulous. Leaf-margin not widely crenate; petiole inserted more than (6-)10 mm from base. |
| 3 | Leaves submembranous, margin often slightly lobed, reticulation scarcely raised and usually drying red-dish brown. Inflorescence usually a solitary axillary cyme. Flowers asymmetrical: sepal 1, petals 2 |
| 3' | Leaves papyraceous to coriaceous. |
| 4 | Drupes sessile or subsessile (excluding ultimate infructescence branchlets). |
| 4' | Drupes pedicellate, apart from occasional sessile ones. |
| 5 | Leaves with a rather lax reticulation, often obscure on upper surface which is often minutely papillose. Endocarp generally suborbicular in outline with 4 dorsal rows of (10—)12—19 hooks. Female flowers asymmetrical |
| 5' | Leaves with a fine reticulation usually visible on both surfaces. Endocarp obovate in outline with 2 or 4 dorsal rows of ridges or lamelliform projections. Female flowers symmetrical. |
| 6 | Leaves with very fine reticulation visible on one or both surfaces. |
| 6' | Leaves with a lax reticulation visible on both surfaces. |
| 7 | Drupes 4-5 mm long. Leaves 5-9 by 4-8 cm. Endocarp with 2 or 4 dorsal rows of 7-9 ridges or papilliform processes. Inflorescences axillary |
| 7' | Drupes 7-10 mm long. Inflorescences usually on old, leafless stems. |
| 8 | Leaves 7-13 by 5-10 cm. Endocarp with 4 dorsal rows of 9-11 very prominent projections, the outer 2 rows lamelliform, dorsal surface very scabrid |
| 8' | Leaves usually more than 16 by 10 cm. Endocarp with 4 dorsal rows of 9-14 short papilliform pro-cesses or low ridges (sometimes T-shaped), dorsal surface slightly rough or smooth |
| 9 | Leaves triangular-orbicular to orbicular, apex rounded to very broadly obtuse. |
| 9' | Leaves triangular to ovate, apex acute to obtuse. |
| 10 | Leaves ovate to ovate-triangular, apex obtuse |
| 10' | Leaves triangular to narrowly triangular, apex very acute |
| 11 | Leaves with a lax and rather obscure reticulation, apex often caudate; petiole inserted more than 10 mm from base |
| 11' | Leaves with a close, raised reticulation, apex shortly acuminate; petiole inserted 3-7 mm from base |
