Herbs annual. Stems erect or ascending, 40-80 cm tall, branched or simple, sparsely pubescent or glabrescent. Petiole 5-8 mm, appressed hispidulous; leaf blade lanceolate or elliptic, often with a dark triangular spot at middle, both surfaces appressed hispidulous, densely so along midvein, base narrowly cuneate, margin largely ciliate, apex acute or acuminate; ocrea tubular, 1-2 cm, membranous, sparsely pubescent, apex truncate, cilia 0.4-3 mm. Inflorescence terminal or axillary, spicate, 2-6 cm, usually several spikes aggregated and panicle-like; peduncle glandular hairy or glabrous; bracts funnel-shaped, ciliate, each 5-7-flowered. Pedicel 2.5-3 mm. Perianth reddish or deep purple, usually 5-parted; tepals oblong, 2.5-3 mm, distinctly veined. Stamens 6 or 7. Styles 2, rarely 3, connate to below middle. Achenes included in persistent perianth, black-brown, shiny or opaque, suborbicular or broadly ovoid, biconvex, rarely trigonous, 2-2.5 mm, smooth. Fl. Jun-Jul, fr. Jul-Sep. 2n = 22, 42.
Plants annual, (0.5-)1-7(-13) dm; roots also often arising from proximal nodes; rhizomes and stolons absent. Stems procumbent, decumbent, ascending, or erect, simple or branched, without obvious ribs, glabrous or appressed-pubescent. Leaves: ocrea light brown, cylindric, 4-10(-15) mm, chartaceous, base inflated, margins truncate, ciliate with hairs 1-3.5(-5) mm, surface glabrous or strigose, rarely with spreading hairs, not glandular-punctate; petiole 0.1-0.8 cm, glabrous or strigose, leaves sometimes sessile; blade often with dark triangular or lunate blotch adaxially, lanceolate to narrowly ovate, (1-)5-10(-18) × (0.2-)1-2.5(-4) cm, base tapered or cuneate, margins antrorsely strigose, apex acute to acuminate, faces glabrous or strigose, especially along midveins, sometimes glandular-punctate abaxially. Inflorescences terminal and axillary, erect, usually uninterrupted, 10-45(-60) × 7-12 mm; peduncle 10-50 mm, glabrous or, rarely, pubescent; ocreolae overlapping or sometimes interrupted proximally, margins ciliate with bristles 0.2-1.3(-2) mm. Pedicels ascending, 1-2.5 mm. Flowers 4-14 per ocreate fascicle, homostylous; perianth greenish white proximally and roseate distally or entirely roseate, not glandular-punctate, scarcely accrescent; tepals 4-5, connate ca. 1/ 3 their length, obovate, 2-3.5 mm, veins prominent, not anchor-shaped, margins entire, apex obtuse to rounded; stamens 4-8, included; anthers yellow or pink, ovate; styles 2-3, connate proximally. Achenes included or apex exserted, brownish black to black, discoid or biconvex to 3-gonous, (1.9-)2-2.7 × (1.5-) 1.8-2.2 mm, shiny, smooth. 2n = 44.
Erect, 20-100 cm tall, annual, glabrous, simple-branched herb, rooting at the nodes. Stem brownish-reddish brown, glabrous. Leaves 1.0-14.0 x 0.25-3.5 cm, narrowly lanceolate-elliptic, acuminate, glabrous - pubescent, entire, subsessile, often with a large dark blotch near the middle on the dorsal side, petiole 1-3 mm long. Ochreae 0.4-1.75 cm long, ovate, usually hirsute, ciliate or fimbriate, ciliae 0.2-1.75 cm or more long. Inflorescence 2.0-3.0 (-3.5) cm long, many-flowered, pedunculate raceme; peduncle 1-2 cm long, eglandular. Flowers 1.5-2 mm across, pedicel 1.0-2.0 mm long. Ochreolae broadly ovate, ciliate, ciliae quite long, sometimes short. Tepals 5, dark pink-red, eglandular, biseriate, unequal; obovate, obtuse. Stamens 6, filaments long, unequal. Ovary ovoid, rounded, with 2 styles, style free above, fused below; stigma capitate. Nuts (1.8-) 2-2.25 (-2.5) x c. 1.5 mm, biconvex, black, shining, glabrous, enclosed by the perianth.