Alternanthera Forssk.
Fls in sessile axillary congested clusters. Per. 5-partite; fertile stamens 2-3, filaments connate at base, anthers 1-celled; style very short or obsolete, stigma us. capitate; ovules solitary, pend. from basal funicle. Utricle compressed, margins often thickened or winged; seed vertical, lenticular. Herbs, us. decumbent, with opp. lvs. About 170 spp., mainly tropical and subtropical.
