Annuals or biennials, 30–70 cm. Phyllaries 8(–12), mostly linear to narrowly oblanceolate. Rays 0. Disc florets 10–20; corollas creamy to bright yellow, mostly 4–4.5 mm, lobe lengths 0.3–1 times throats; anthers yellowish. Cypselae 2.5–4+ mm; pappus scales 3–5 mm. 2n = 24.

Flowering summer–fall. Open, often disturbed, places; 900–2100 m; Ariz., Calif., Nev.

Occurrences of Hymenothrix loomisii in California have been geographically scattered, sporadic, and nonpersistent introductions.