Stems glabrous. Leaves: petiole glabrous; blade margins not rev­olute, not ciliate, surfaces gla­brous. Calyces glabrous (sepal margins seldom sparsely ciliate or rarely papillate).

Flowering spring(–summer); fruiting (spring–)summer(–fall). Dry, rocky hills, mesas, scrub, limestone flats, roadsides, generally on limestone; 900–1500 m; N.Mex., Tex.; Mexico (Coahuila).