1	"Leaves succulent; bracts leaf-like"	2
1	"Leaves not succulent; bracts not leaflike (either membranous or spine-like)"	3
2	"Prostrate to trailing perennial herbs, young branches pubescent; stamens 5"	"Hemichroa: Hemichroa pentandra"
2	"Decumbent to erect shrubs, young branches glabrous to papillose; stamens 2"	"Surreya: Surreya diandra"
3	"Leaves alternate, spirally arranged"	4
3	"Leaves opposite"	8
4	"Perianth segments (tepals) glabrous"	5
4	"Perianth segments (tepals) hairy for some or all of length on outside or inside surface"	7
5	"Fruit a berry; vine or scrambling perennial shrubs"	Deeringia
5	"Fruit an indehiscent utricle or circumscissile capsule; annual or perennial herbs"	6
6	"Flowers always bisexual; seeds 4 to 12 (more than one); style single, long, > 4 mm long; staminal filaments united for lower half; pseudostaminodes present, minute"	"Celosia: Celosia argentea"
6	"Flowers always unisexual; Seed one; style absent or very short, < 2 mm long; staminal filaments free; pseudostaminodes absent"	Amaranthus
7	"Stigmas capitate"	Ptilotus
7	"Stigmas bifid"	"Aerva: Aerva javanica"
8	"Modified sterile flowers (formed of hooked spines) present, frequently one on each side of a fertile flower"	Pupalia
8	"Modified sterile flowers absent; single fertile flower in bract axil only (sometimes inflorescence condensed but every flower in head will have its own bract)"	9
9	"Perianth segments (tepals) fused into a tube for at least half the length"	"Guilleminea: Guilleminea densa"
9	"Perianth segments (tepals) fused for less than half of the length or free to base"	10
10	"Bracteoles spiny, bracts reflexing with age"	"Achyranthes: Achyranthes aspera"
10	"Bracteoles never spiny, bracts never reflexing"	11
11	"Flowers unisexual; anthers bilocular"	"Ptilotus: Ptilotus crispus"
11	"Flowers bisexual; anthers unilocular"	12
12	"Inflorescences always axillary; stigma capitate"	Alternanthera
12	"Inflorescence terminal or terminal and axillary; stigma bilobed to bifid"	Gomphrena