Annual herb, erect or more rarely ascending, 10-75 (-100) cm. Stem rather slender, sparingly to considerably branched, angular, glabrous or more frequently increasingly hairy upwards (especially in the inflorescence) with short or longer and rather floccose multicellular hairs. Leaves glabrous or shortly to fairly long-pilose on the lower surface of the primary and most of the venation, long-petiolate (petioles up to c. 10 cm long and the longest commonly longer than the lamina), lamina deltoid-ovate to rhomboid-oblong, 2-7 x 1.5-5.5 cm, the margins occasionally obviously sinuate, shortly cuneate to sub-truncate below, obtuse and narrowly to clearly emarginate at the tip, minutely mucronate. Flowers green, in slender, axillary or terminal, often paniculate spikes c. 2.5-12 cm long and 2-5 mm wide, or in the lower part of the stem in dense axillary clusters to c. 7 mm in diameter; male and female flowers intermixed but the latter more numerous. Bracts and bracteoles deltoid-ovate to lanceolate-ovate, whitish-membranous with a very short, pale or reddish awn formed by the excurrent green midrib, bracteoles shorter than the perianth (c. 1 mm.). Perianth segments 3, very rarely 4, those of the male flowers oblong-oval, acute, concave, c. 1.5 mm, shortly mucronate; those of the female flowers narrowly oblong to narrowly spathulate, finally 1.25-1.75 mm, minutely mucronate or not, the borders white-membranous, midrib green and often thickened above. Stigmas 2-3, short, erect or almost so. Capsule subglobose, 1.25-1.5 mm, not or slightly exceeding the perianth, indehiscent or rupturing irregularly, very strongly rugose throughout. Seed c. 1-1.25 mm, round, only slightly compressed, dark brown to black with an often paler thick border, ± shining, reticulate and with shallow scurfy verrucae on the reticulum, the verrucae with the shape of the areolae.