Stems sparsely to moderately prickly. Leaf blades: basal and proximal lobed nearly to midrib. Inflorescences: sepal horns 4-6(-l0) mm, unarmed or sparingly prickly near base. Capsules usually narrowly ellipsoid, surface partially obscured, longer prickles widely spaced, interspersed with numerous, shorter, unequal ones. 2 n = 28. Flowering early spring-summer; fruiting spring-fall. Pastures and waste ground; 0-300 m; Ark., La., Mo., Tex. Argemone albiflora subsp. texana is introduced in Arkansas and Missouri.