Herbs usually much-branched from base, glandular-pubescent but often glabrate. Leaves: larger ones 3 times pinnatifid, ultimate lobes narrow, rounded, and often elongate. Seeds 3.1–3.6 mm.

Flowering Jun–Nov. Open desert, semidesert, calcar­eous or gypsum hills, bajadas, flats; (70–)600–1300 m; Tex.; Mexico (Coahuila, Durango, Nuevo León).

Variety tenuipes is found in Brewster, Crockett, Maverick, and Terrell counties.