1 | Leaves simple. |
1' | Leaves compound, usually imparipinnate, sometimes tri- or unifoliolate, rarely pseudoparipinnate or paripinnate. |
2 | Leaves decussate |
2' | Leaves spiral or alternate. |
3 | Calyx caducous, calyptriform. Petals caducous, or persistent and enlarged (wing-like) in fruit |
3' | Calyx persistent (except in some specimens of Buchananid), distinctly 4- or 5-lobed. |
4 | Fruit developed from an inferior ovary and crowned with persistent floral parts. |
4' | Ovary and fruit superior and subtained by the persistent floral parts. |
5 | Petals persistent, usually (much) enlarged, wing-like, and reflexed in fruit |
5' | Petals usually caducous and not enlarged in fruit. |
6 | Fruit with a distinct or conspicuous hypocarp. |
6' | Fruit without a hypocarp. |
7 | Leaf lower surface not papillose. Fruits reniform |
7' | Leaf lower surface often papillose. Fruits not reniform |
8 | Fruits incompletely 2-celled. Seed curved. Leaves usually with dense or sparse, minute, peltate or lobed scales on both surfaces |
8' | Fruits 1-celled. Seed or embryo (if testa confluent with endocarp) straight. Leaves without scales like above. |
9 | Fruit with 3-5 stigmas or vestiges of undeveloped carpels close to one side at the base 1. Buchanania, |
9' | Fruit without stigmas or such vestiges of undeveloped carpels. |
10 | Fruits subglobose, ½-⅔ cm Ø |
10' | Fruits larger, usually longer than wide; if globose or subglobose then (1—)2½ or more cm Ø. |
11 | Fruits glabrous; flesh juicy and without black varnish. Leaves glabrous, not papillose beneath |
11' | Fruits hairy; flesh thin and full of black varnish. Leaves often hairy and/or papillose beneath in most species |
12 | Leaflets with a distinct, continuous, intramarginal vein |
12' | Leaflets without such intramarginal vein. |
13 | Calyx (much) enlarged and lobes wing-like in fruit |
13' | Calyx not enlarged in fruit. |
14 | Lower surface of leaflets with domatia. |
14' | Lower surface of leaflets without domatia. |
15 | Domatia not hairy, each of them like a pit or cavity. Fruits obliquely subglobose, less than 1 cm Ø |
15' | Domatia hairy, each of them consisting of a tuft of hairs. |
16 | Climbers. Fruits broad-ellipsoid or slightly reniform, 1¼-1½ by c. 4/5 cm; flesh full of black varnish |
16' | Trees. |
17 | Fruits 1-celled; endocarp coriaceous, not hard |
17' | Fruits 5-12-celled; endocarp woody and hard. |
18 | Endocarp with an operculum covering each cell |
18' | Endocarp without such opercula |
19 | Leaflets usually 10-16 pairs. Fruits broad-ellipsoid, obtuse at both ends, 2½-4 by 1ll2-2ll2 cm |
19' | Leaflets usually 2-7 pairs, sometimes tri- or unifoliolate. |
20 | Endocarp with 1 (or 2) distinct operculum (opercula) at the apical end. |
20' | Endocarp without distinct operculum (opercula). |
21 | Fruits c. 1 cm long. Seed reniform. Young twigs, leaflets, and inflorescences with stellate hairs |
21' | Fruits larger, 2-2½ cm long. Seed oblong. Young twigs, leaflets, and inflorescences with simple hairs |
22 | Fruits scurfy outside, lanceolate, 2½ by 1 cm. Leaflets velutinous on the lower surface |
22' | Fruits glabrous, variously shaped but not lanceolate, less than 1½ by ⅔ cm. |
23 | Fruits ± oblong, or obliquely broad-ellipsoid; style or its scar excentric. |
23' | Fruits obliquely subglobose, or globose; style or its scar terminal. |
24 | Fruit with style or its scar on one side at the upper ⅓.Terminal leaflet similar to the lateral ones |
24' | Fruit with style or its scar lateral at the apical end. Terminal leaflet usually very small, reduced, or not developed |
25 | Leaves distinctly imparipinnate, tri- or unifoliolate. Endocarp free from exocarp and mesocarp when ripe |
25' | Leaves pseudoparipinnate or paripinnate. Endocarp united with exocarp and mesocarp when ripe |