Eclipta L.

Annual or perennial herbs; stems usually weak, procumbent, annual. Leaves simple, opposite, sessile to shortly petiolate, linear to lanceolate or elliptic, entire to minutely toothed, 3-veined (sometimes obscurely); base rounded to attenuate. Capitula solitary or in dichasial clusters in upper leaf axils, radiate; involucral bracts in 2 series, ±equal, herbaceous; receptacle paleate; paleae narrowly linear, keeled, sparsely hairy, sometimes absent from central florets. Ray florets in several series, female or sterile; ligule narrow, usually 2-lobed, white or yellow. Disc florets bisexual, fertile; corolla 4-lobed; anther sacs yellow or black; pappus a membranous cup, sometimes produced into 2–4 short weak awns, rarely absent. Immature achenes smooth; mature achenes slightly dimorphic, oblong, tuberculate, with marginal achenes ±3-angled, others 4-angled, angles sometimes thickened and cartilaginous, or winged. Pappus a short, entire or toothed crown of connate scales, sometimes appearing to be 2–4 short soft awns.