Xanthoparmelia namakwa is a species of saxicolous (rock-dwelling), foliose lichen in the family Parmeliaceae. Found in South Africa, it was formally described as a new species in 1986 by the American lichenologist Mason Hale. The type specimen was collected from Cape Province at an elevation of , where it was found growing on schist rock outcrops in flat pasture land. The lichen has a dark yellow-green thallus that is firm and leathery in texture, and measures broad. The species epithet refers to Namaqualand, a geographic area in which the type locality is situated. The lichen contains salazinic acid, norstictic acid, and usnic acid, and sometimes trace levels of other lichen substances.