Erect, annual, scabrid or villous herb; stem sparingly branched, terete, hispidly hairy; leaves opposite or upper alternate, petioled, ovate-crenate-serrate, 3-nerved, pubescent on both surfaces; heads heterogamous, small, subsessile in erect, terminal or axillary; involucral bracts 2-seriate, outer bracts herbaceous, ovate, oblong, hairy outside, inner bracts paleaceous, small, rigid; ray florets, female, 1-2 seriate, inconspicuous, ligule white, 2-3 lobed; disk florets bisexual, fertile, tubular, corolla white, dilated, 5-fid; anther lobes obtuse at base; ovary 1-celled, 1-ovuled, solitary, basal, obtuse, style arms elongate, obtuse; style arms narrow, flattened with acute or subobtuse appendages; achenes of ray truncate, triquetrous or dorsally compressed, of disk usually laterally compressed; pappus of 2-5, unequal, bristles connate at base.