in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 74. 1859.
Shrubs or treelets, mostly 100–300 cm. Stems (1–5+), branched. Leaves cauline; alternate; sessile; blades linear-filiform, rarely with 1–2 lateral lobes, ultimate margins entire, faces glabrous, gland-dotted. Heads discoid, borne singly. Involucres turbinate to campanulate, 6–12 mm diam. Phyllaries persistent or tardily falling, 8–18 in ± 2 series (linear to lanceolate, outer intergrading with subtending leaves). Receptacles flat, pitted or knobby, epaleate. Ray florets 0. Disc florets 12–21, bisexual, fertile; corollas creamy yellow, distally purplish (stipitate-glandular), tubes shorter than cylindric throats, lobes 5, erect, deltate (style-branch appendages rounded-truncate, papillate). Cypselae obconic to obpyramidal, hirsute (hairs tawny to reddish); pappi persistent, of 30–60 bristles subtending 15–20 subulate-aristate scales, or of ca. 120 bristles. x = 10.
sw United States, nw Mexico.