1	"Leaves alternate or all radical."	2
1	"Leaves opposite."	5
2	"Woody climbers; fruit a red berry."	Deeringia
2	"Annual or perennial herbs or subshrubs; fruit dry."	3
3	"Inflorescence and perianths mostly glabrous; filaments free; fruit 1-seeded."	Amaranthus
3	"Inflorescence and perianths variously hairy; filaments fused at the base; fruit with 1 or more seeds."	4
4	"Fruit with 2 or more seeds; flowers mostly in simple terminal spicate inflorescences; anthers 2-locular."	Ptilotus
4	"Fruit with 1 seed; flowers in terminal and lateral spicate inflorescences; anthers 4-locular"	Aerva
5	"Perianth rigid, especially in fruit."	6
5	"Perianth membranous or scarious in fruit, not rigid."	9
6	"Perianth segments 4; bracts spinescent, spreading in fruit."	Nyssanthes
6	"Perianth segments 5; bracts variously armed, not spreading in fruit."	7
7	"Inflorescence an axillary cluster."	Alternanthera
7	"Inflorescence a terminal spike."	8
8	"Flowers not reflexed in fruit; bracts not pungent."	Froelichia
8	"Flowers reflexed in fruit; bracts pungent."	Achyranthes
9	"Stigma bifid; at least some bracts subequal to perianth."	Gomphrena
9	"Stigma entire; bracts shorter than perianth."	10
10	"Perianth segments fused to c. halfway; inflorescence woolly."	Guilleminea
10	"Perianth segments free or almost so; perianths glabrous or variously hairy but inflorescence not woolly."	Alternanthera