1Petals imbricate. Tribe Aralieae.
1'Petals valvate.
2Leaves simple, palmately or pinnately lobed, or entire.
2'Leaves pinnately compound (or bi- or tripinnate).
3Leaves palmately lobed, tomentose
3'Leaves pinnately lobed or entire, glabrous.
4Leaves twice (or more) pinnate
4'Leaves once pinnate.
5Leaflets many
5'Leaflets 5 or fewer
6Petals with a narrow base, or claw. Tribe Mackinlayeae
6'Petals with a broad base. Tribe Schefflereae.
7Inflorescence rays trifid: central branch shorter with 'false fruits', the two lateral longer with normal flowers
7'Inflorescence branches not as above.
8Ovary with one cell
8'Ovary with more than one cell.
9Leaves pinnate.
9'Leaves not pinnate.
10Pedicel not articulated below the flower
10'Pedicel articulated below the flower
11Pedicel articulated below the flower.
11'Pedicel not articulated below the flower.
12Leaves digitately compound (or rarely unifoliolate) (Malay Peninsula, Sumatra, Java)
12'Leaves simple, not articulated with the petiole (West New Guinea).
13Leaf simple (or unifoliolate) or palmately lobed.
13'Leaf digitately compound.
14Leaf palmately lobed.
14'Leaf simple (or unifoliolate).
15Ovary 2-celled
15'Ovary 10- or more-celled
16Articulation present between petiole and blade
16'No articulation between petiole and blade.
17Ovary 2-celled
17'Ovary 4- or more-celled
18Petiolules joined together by a web of tissue
18'No such web of tissue present.
19Styles or stigmas 2.
19'Styles or stigmas more than 2
20Style bifid
20'Styles united into a column