P. laui is a magnificent exemplar of a small, solitary cactus growing in the rocky and mountainous areas of Bolivia. It has a globose stem tending to be cylindrical, of pale green colour. Its ribs are well marked, on them we can notice the white and woolly areoles from which radial and central thorns come out. The first ones are thin, yellowish and slightly hooked while the central ones are more robust and of a darker tonality. During the flowering period this wonderful cactus gives bell-shaped flowers with bright colors ranging from orange to red-orange and with a median line of darker shades.