Polygala subspinosa
 Polygala subspinosa is a species of flowering plant in the milkwort family known by the common name spiny milkwort. It is native to the southwestern United States where it grows in desert and plateau habitat. It is a perennial herb or small shrub growing in a clump no more than 25 centimeters tall. The stems have woody bases and green thorn-tipped branches. The leaves are up to 3 centimeters in length and generally oval in shape.