Herbs, annual; taproot slender. Stems arising directly from the root, erect to spreading, solid, not fistulose or disarticulating into ringlike segments, sparsely glandular-pubescent. Leaves usually quickly deciduous, basal, rosulate; petiole absent; blade spatulate to obovate, margins entire. Inflorescences terminal, cymose, uniparous due to suppression of secondaries; branches dichotomous, not brittle or disarticulating into segments, round, sparsely glandular-pubescent; bracts 3(–5), positioned to side of node or perfoliate and completely but unequally surrounding node, connate nearly completely, triangular to ovate or oblong, awned, sparsely glandular-pubescent. Peduncles absent. Involucres 1–3 per node, tubular, cylindric, (2–)3–4-angled, slightly ventricose on the angles in some; teeth (2–)3–4, awn-tipped. Flowers 1(–2) per involucre; perianth white to pink, campanulate when open, cylindric when closed, pubescent abaxially; tepals 6, connate ca. 1/3 their length, monomorphic, entire or erose to fimbriate apically; stamens 6–9; filaments free, glabrous; anthers pink to red, oblong. Achenes mostly included, brown to black, not winged, globose-lenticular, glabrous. Seeds: embryo straight. x = 19.
Species 2 (2 in the flora).
|1||Inflorescence bracts positioned to side of node, involucres 1-3 per node, 2.5-5(-7) mm,bracts (2-)3(-4), awns (0.5-)1-2.5 (3) mm; flowers 1-2; tepals entire apically||Mucronea californica|
|1||Inflorescence bracts perfoliate; involucres 1 per node, 3-5(-6) mm, bracts 4, awns (0.3-)0.5-1.2 mm; flowers 1; tepals entire to fimbriate apically||Mucronea perfoliata|