Xanthoparmelia maricopensis, the Maricopa rock-shield, is a 2–6 cm (0.8–2.4 in) wide, yellow-green foliose lichen in the Parmeliaceae family. It grows on igneous rock in southwestern North American deserts.[1][2][3]
The thallus is tightly attached to the substrate, with irregular somewhat shiny 1–2 mm lobes.[2] It differs from Xanthoparmelis dierythra in that it has hyposalazinic acid and the lobes are usually more narrow and convex. The lower surface is tan and has unbranched rhizenes.[3]
The upper cortex is K−, C−, KC−, and P−. The medulla is K+ yellow to orange, C−, KC−, P+ orange.[2] The upper cortex has usnic acid as a secondary metabolite.[2] The medulla has norstictic acid and traces of hyposalazinic acid and connorstictic acid.[2]
It is common in lower elevations of the Sonoran Desert in Arizona, southern California, and north and south Baja California to Chihuahua, Mexico and Sonora Mexico.[2] In Joshua Tree National Park it grows on non-calcareous rock, soil, basalt, gneiss, and monzogranite.[1]
Xanthoparmelia maricopensis, the Maricopa rock-shield, is a 2–6 cm (0.8–2.4 in) wide, yellow-green foliose lichen in the Parmeliaceae family. It grows on igneous rock in southwestern North American deserts.