Bonplandia (Corrientes) 3: 59. 1970.
Stems prostrate, indument mixture of stellate and appressed, sublepidote hairs. Leaves: petiole 1/2–1 times as long as blade; blade ± reniform, 1–3.5 cm, wider than long, base obliquely truncate, margins serrate, apex obtuse or subacute, surfaces densely hairy, hairs appressed, sublepidote and stellate. Pedicels long, subequal to subtending petiole; involucellar bractlets 3, inconspicuous, filiform, or 0. Flowers: calyx 8–10 mm, with mixture of stellate and appressed sublepidote hairs, lobes ovate, bases not plicate-overlapping, apex acuminate; petals pale yellow, sometimes with rose flush on fading, asymmetric, 12–15 mm; stamens pallid, glabrous, staminal column antheriferous at apex; style 7–10-branched, pallid, glabrous. Schizocarps 7 mm diam. 2n = 22, 32.
Phenology: Flowering year-round in warmer areas.
Habitat: Heavy, saline soil
Elevation: 800–1500 m
Ariz., Calif., Colo., Idaho, Kans., Nev., N.Mex., Okla., Oreg., Tex., Utah, Wash., Mexico (Baja California, Chihuahua, Coahuila, Durango, San Luis Potosí, Sinaloa, Sonora), South America (Argentina, Chile, Peru, Uruguay).
Malvella leprosa is possibly introduced in Colorado. The species is considered to be a noxious weed in Arizona and California and increasing as saline soils increase.