Plants subscapose, to 2.5 dm. Leaves 1-8 cm; blade shallowly to deeply 3-5-lobed distally, to 1.6 cm wide distally, minutely hirsute, sparsely long-pilose. Inflorescences 2-7-flowered, branching, glabrous or nearly so; buds glabrous. Flowers: sepals glabrous; petals marcescent, 4, white, 1.2-2.5 cm; filaments somewhat dilated distally; style 1 mm. Capsules ovoid, 0.8-1.5 cm, dehiscing 1/3-1/2 length, deciduous soon after. 2 n = 24. Flowering late spring; fruiting mid summer. Barren, heavily gypsiferous shales, creosote bush zone; of conservation concern; 700-1100 m; Utah. Extant populations of Arctomecon humilis are known only from the area within 20 km of St. George in extreme southwestern Utah.