Monoecious annual herbs; stems sometimes tinged reddish or yellowish; erect, ascending, or prostrate, 0.6-6 (-9) dm long, unbranched or branched, striate, glabrous, rarely with unicellular to multicellular short hairs, especially above. Leaves ovate to rhombic-ovate, blades 1-8 cm long, 0.6-6 cm wide, glabrous, rarely the lower surface with scattered multicellular hairs along the veins, apex usually broad, widely emarginate, petioles 0.5-10 cm long. Flowers green, in slendere to stout axillary or terminal spikes, rarely panicles, both sexes mixed throughout the spikes, bracts and bracteoles whitish, deltate-ovate to lanceolate, membranous, tipped with a short yellow or reddish mucro; sepals 3 (4), lanceolate-oblong to spatulate, 0.7-2 mm long, apex subacute, mucronate, apex of pistillate flowers often more blunt; stigmas 2-3. Fruit globose to pyriform, compressed, exceeding the sepals, 1.2-2.5 mm long, indehiscent or rupturing irregularly at maturity, the surface smooth, occasionally wrinkled upon drying. Seeds dark brown to black, shiny, the margins duller, compressed, 1-1.8 mm long, faintly reticulate, minutely punctate-roughened. |