Hymenatherum pentachaetum de Candolle in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 642. 1836; Dyssodia pentachaeta (de Candolle) B. L. Robinson

Perennials or subshrubs, ± grayish to green, to 15(–25) cm, usually puberulent to canescent, sometimes glabrescent or glabrous. Stems erect or spreading. Leaves mostly opposite; blades mostly pinnately lobed, 6–28+ mm overall, lobes 3–11 linear to filiform (usually stiff, setiform). Peduncles 20–100 mm, puberulent or glabrous. Calyculi 0, or of 1–5 deltate bractlets, lengths less than ¹/2 phyllaries. Involucres obconic to campanulate or hemispheric, 4–6 mm. Phyllaries 12–21, margins of outer distinct ¹/5 to nearly all their lengths, abaxial faces puberulent or glabrous. Ray florets (8–)12–21; corollas yellow to orange-yellow, laminae 2–6(–8) × 1–3 mm. Disc florets 16–40 or 50–80; corollas yellow, 2–4 mm (tending to zygomorphy in peripheral florets in some plants). Cypselae 2–3 mm; pappi of 10 erose and/or aristate scales mostly 1–3 mm.

Varieties 4 (4 in the flora): sw United States, Mexico; introduced(?) in South America (Argentina).