Xanthoparmelia namaquensis 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 growing on a sun-exposed sandstone cliff. The lichen, loosely attached to its rock , has a yellowish-green thallus that darkens towards the center, and measures in diameter. It contains lecanoric acid and usnic acid, and an unnamed bright pinkish-orange anthraquinone pigment. The species epithet refers to Namaqualand, an arid region of southern Africa to which this species seems to be restricted.