KEY TO THE GENERA

1Leaves simple, entire or lobed
1'Leaves compound, pinnate, palmate, or 3-foliolate
2Herbs
2'Woody plants, trees or shrubby
3Flowers small, with epicalyx, without petals, with 1-5 stamens. Achenes enclosed in hard hypanthium
3'Flowers usually showy, without epicalyx, petals only in few species absent, stamens numerous. Drupes cohering and forming a collective fruit
4Ovary or ovaries superior, not connate with the hypanthium
4'Ovary inferior or semi-inferior, carpels connate with the hypanthium, either entirely or at least their lower half
5Flower with 1 pistil (exceptionally 2)
5'Flower with more than 2 pistils
6Small shrubs. Leaves 3-lobed. Glands on the hypanthium outside, elongating after anthesis. Fruits dehiscent, with several seeds
6'Trees or shrubs. Leaves not lobed. Hypanthium without long-stalked glands. Fruit a drupe with 1 stone
7Plants climbing, straggling, or creeping, rarely erect, usually armed. Stipules present. Fruits cohering as a collective, each of the juicy drupes with one stone
7'Erect shrubs, not armed. Stipules absent. Fruit a dehiscent follicle with several seeds (cultivated)
8Simple racemes
8'Racemes branched and compound
9Styles free. Fruits with stone-cells in mesocarp (cultivated)
9'Styles connate at base. Fruits without stone-cells (cultivated).
10Plants with thorns (cultivated)
10'Plants without thorns
11Upper rim of hypanthium and sepals persistent on the fruit. Ovary semi-inferior
11'Sepals and upper rim of hypanthium deciduous after flowering, leaving a scar on top of the fruit. Ovary inferior
12Main nerves terminating in the margin
12'Main side-nerves not terminating in the margin
13Rower with 2 carpels, in their basal half adnate to the hypanthium, but free from each other (cultivated)
13'Flower with up to 5 carpels, connate with each other and with the hypanthium
14Evergreen. Ovary 2-celled. Fruits 1-, rarely 2-seeded, seeds thick, cotyledons thick
14'Deciduous. Ovary usually 3-celled (2-4). Fruits with usually 2 seeds per cell, seeds flat, cotyledons flat
15Herbs
15'Plants with woody branches
16Flowers in globular heads, without petals
16'Flowers not in heads. Petals present
17Sepals imbricate. Male and bisexual flowers with 10-30 stamens (cultivated)
17'Sepals valvate. Flowers bisexual, with 2 or 3 stamens
18Epicalyx absent. Pistils usually 2, remaining enclosed in the hypanthium which bears many erect spines under the calyx
18'Epicalyx present. Pistils on a more or less elevated torus, not completely enclosed by the spineless hypanthium
19Petals yellow
19'Petals white (cultivated)
20Achenes hidden in the hollowed, fleshy hypanthium
20'Drupes forming a collective fruit, on an elevated torus