Herbs [or subshrubs], annual [or perennial]; taproot slender to stout. Stems prostrate or decumbent to erect, pubescent; aerial flowering stems arising [at nodes of caudex branches, at distal nodes of aerial stems or] directly from the root, decumbent to erect, slender [to stout and solid, not disarticulating in ringlike segments], sometimes disarticulating at each node. Leaves persistent or quickly deciduous, basal and rosulate or basal and cauline, alternate; petiole present; blade linear to oblanceolate or spatulate, entire apically. Inflorescences terminal, cymose or capitate, uniparous due to suppression of secondaries; branches open and spreading or erect, typically trichotomously branched at proximal node, otherwise dichotomous, sometimes brittle and disarticulating into segments, round, pubescent [or rarely glabrous]; bracts mostly 2, opposite, sometimes numerous, whorled, distinct, leaflike to subulate or linear, occasionally awn-tipped, thinly pubescent (sometimes appressed), hirsute, villous, strigose, or tomentose, rarely woolly-floccose or minutely glandular. Peduncles absent. Involucres 1-6+ per node, 3-6-ribbed, tubular, cylindric to urceolate or turbinate to campanulate; teeth 3, 5, or 6, awn-tipped. Flowers bisexual, 1(-2) per involucre, pedicellate; perianth white to yellow or pink to rose-pink, red, maroon or purple, cylindric, funnelform, or campanulate when open, cylindric when closed, glabrous or pubescent abaxially; tepals (5-)6, connate 3 their length, monomorphic or dimorphic, entire, emarginate, or lobed to laciniate apically; stamens 3, 6, or 9, or variously 3-9; filaments distinct or connate into staminal tube, sometimes adnate to floral tube, glabrous or pubescent; anthers maroon to red or cream to white or yellow, oval to oblong; styles erect to spreading. Achenes included, light brown to dark brown or black, not winged, lenticular, globose-lenticular, or 3-gonous, glabrous. Seeds: embryo straight or curved. x = 10.
