KEY TO THE GENERA OF THE MOREAE

1Plants herbaceous (or suffrutescent)
1'Plants woody
2Shoot apices deciduous
2'Shoot apices persistent
3Tepals of the pistillate flowers free; stigmas 2, equal
3'Tepals of the pistillate flowers connate; stigma 1, or if 2, then unequal
4Plants armed with curved or straight spines; pistillate inflorescences globose-capitate; tepals and bracts mostly with yellow dye accumulated in immersed glands
4'Plants unarmed, or if armed, then with straights spines; the pistillate inflorescences not globose-capitate and tepals and bracts without yellow dye containing glands
5Plants mostly with thorns or lamina scabrous above; inflorescences spicate or unisexual; tepals of the pistillate flowers (almost) free
5'Plants without thorns, lamina smooth above; inflorescences cymose if bisexual; tepals of the pistillate flowers connate
6Inflorescences bisexual, cymose; tepals of the staminate flowers 4 or 5
6'Inflorescences unisexual, spicate; tepals of the staminate flowers 4 or 3