, one of only six species in the crossosomataceae family, is a small to medium-sized shrub, up to 6 feet tall, inhabiting rocky areas in the Sonoran and Mojave deserts. It has woody stems, grey to reddish, bearing bundles of small, quite thick leaves at closely-spaced intervals. Leaves have a tiny spine at the (blunt) tip.
Flowers are solitary, on stalks at the end of the branches. The five sepals are pale green (purple when in bud), broadly ovate to round, slightly hooded, while the five petals are white, sometimes tinged with purple, narrowly oblanceolate to lanceolate, and about three times as long, up to 0.5 inches. Petals are recurved when mature, arching down below the sepals. The flower center contains between 15 and 30 stamens, and two carpels.