Amaranthus 莧屬
型態特徵
Monoecious, erect or prostrate, sometimes spinous, annual herbs; stems branched, glabrous or pubescent. Leaves petiolate, alternate, entire, penninerved. Flowers unisexual, or polygamous, small, green, occasionally white or purplish, clustered; clusters axillary or terminal spikes or panicles; bracts often tipped with spines, sometimes minute; bracteoles 2; perianth-segments 3 or 5, rarely 4, membranaceous, glabrous; stamens 2–5, filaments free, anthers 2-celled; ovary ovoid, with an erect ovule, style very short, stigmas 2–4, filiform. Utricles laterally compressed, indehiscent or circumscissile; seed solitary, lenticular, shining, smooth, with annular embryo.
Species about 50, of world-wide distribution; four species in Taiwan.