Annual, little to profusely branching herbs, erect to spreading and rooting at the lower nodes, to 5.5 dm tall; stems greenish-red, sparsely to densely hirsute with spreading trichomes of ca. 5 cells, 1-1.5 mm long, more densely pubescent at the nodes. Leaves sessile to subsessile, elliptic to lanceolate-ovate, 0.9-6.2 cm long, 0.3-2.5 cm wide, apically acute to acuminate, basally obtuse to rounded, ciliate, entire to denticulate, sparsely to densely hirsute on both surfaces, green, lighter beneath, prominently 3-veined, more pronounced beneath. Inflorescences with peduncles 0.5-6.5 cm long, slender, flaring at the apex, hirsute, green to reddish, solitary, terminal or axillary, or in cymose clusters. Heads radiate, campanulate, 3-10 mm wide, 3-6 mm tall; involucral bracts uniseriate, free, 5-12, linear-lanceolate, trinerved, 0.6-1.2 mm wide, 2-5.2 mm long, usually densely hispid on the basal half, the wings hyaline, 1.2-2.2 mm long, the margins short ciliate to erose; receptacle narrowly conic, 1-3.4 mm tall, 0.6-1.7 mm wide at the base; paleas linear to obovate, the inner ones narrower, hyaline, generally glabrous, the outermost rarely hirsute, the margins ciliate, convex, enclosing the disc achenes; ray florets fertile, the corollas white to yellow, the ligule oblong to obovate with 2 prominent veins and 2-lobed, or varying to 4-5-veined and 3-lobed, glabrous, 1.3-5 mm long, 0.5-1.8 mm wide, the tube 0.3-0.8 mm long, the style branches recurved, acute; disc florets 12-76, fertile, the corollas yellow, funnelform, the lobes (4)5, acute, often black-dotted, 1-1.7 mm long, 0.3-0.8 mm wide, the tube narrow, ca. 0.3 mm long with a pubescent basal enlargement. Ray achenes shiny black, narrowly obovate, somewhat flattened, 0.8-1.8 mm long, 0.3-0.6 mm wide, minutely striate, glabrous, carpopodium present, epappose but with an annulus 0.1-0.2 mm high; disc achenes 0.9-1.5 mm long, 0.3-0.5 mm wide, shiny black, glabrous, narrowly turbinate, terete to somewhat angular, carpopodium present. Chromosome num-ber n = 18
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