Amaranthus dubius
Content
Description
Erect, monoecious, annual herb 2 m, sometimes becoming much branched, stout and succulent; stems green to pink, glabrous to sparsely puberulent. Petiole shorter than to longer than blade; blade ovate, rhombic to lanceolate, 2-9(-17) x 1-6(-11) cm, entire or somewhat crenulate. Inflorescence of axillary clusters and drooping terminal spikes or panicles, 5-20(-25) cm long; bracts and bracteoles lanceolate, ovate or obovate, much shorter than tepals, midrib prominent. Male flowers mostly in apical portion of terminal inflorescence; tepals 5, oblong-elliptical, 1.7-2 mm long, often mucronate; stamens 5(4). Female flowers in axillary clusters and on lower portion of terminal inflorescence; tepals 5, oblong, 1.3-2 mm long, obtuse to acute, often emarginate and mucronate; styles 2-3. Utricle indehiscent to circumscissile, subequal to slightly exceeding perianth, 1.5-2.5 mm long, obtuse or truncate at apex, roughly wrinkled or rugulose, smooth below, often with apparent line of dehiscence; seed cochleate-orbicular or lenticular, 0.7-1.1 mm wide, dark reddish-brown or black, lustrous.
Distribution
French Guiana present, Guianas present, Guyana present, Pantropical present, tropical America present
Originally tropical America, now pantropical; weed in disturbed areas, or rarely cultivated for the edible leaves in Guyana and French Guiana; 14 collections studied, all from the Guianas (GU: 5; SU: 4; FG: 5).