Diploschistes diacapsis

Diploschistes diacapsis (also called the desert crater lichen) is a ground-dwelling crustose lichen in the family Graphidaceae. It forms a thick, pale grey to greyish-white crust that cracks into small patches. Its fruiting bodies (apothecia) are sunken and often dusted with a powdery coating (pruina), and it produces brown, muriform (multichambered) ascospores. The lichen body (thallus) contains lecanoric and diploschistesic acids. The species typically grows in arid and semi-arid regions on calcium-rich or gypsum soils, where it can form extensive pale carpets within biological soil crusts (surface communities of lichens, mosses, and microbes that bind soil). It is distinguished from similar soil-dwelling species by its thick, heavily pruinose thallus, eight-spored asci (spore sacs), and distinctive chemistry. The species is most often reported from open, exposed habitats on calcareous (lime-rich) or gypsiferous (gypsum-rich) soils, where it can be a conspicuous component of biologic......read more on Wikipedia.