Petalonyx Nitidus, Shinyleaf Sandpaperplant

Petalonyx nitidus is a small shrub inhabiting desert regions, forming low clumps or mounds. The branched stems are woody with age, and new branches are covered by short, rigid, barbed hairs. The bright green leaves are similarly hairy; they have a lighter-colored midvein and pinnate side veins, and their edges are lined with shallow teeth. Leaf tips are pointed.

The inflorescence is a compact, slightly elongated cluster of between 10 and 30 heads, the petals less than half an inch long, extending between 2 and 3 inches at the top of the branches. Each flower is subtended by three ovate bracts; one outer, the other two inner, and smaller. Flowers have a tubular, greenish-yellow corolla, opening to five white, spatula-shaped petals, fused at the (clawed) base. Five stamens are exserted well beyond the petals, topped by yellow anthers.

Petalonyx parryi is a very similar species; it differs in having a larger number of flowers per cluster (35 to 65), and by having shorter branches - yearly growth up to 5 inches, cf. up to 14 inches for petalonyx nitidus.