Agonimia tristicula (Nyl.) Zahlbr.

An Agonimia species with (at least in central Europe) mostly sterile thallus made up of grey to brownish-green squamules. These often have granular to finger-like protuberances. The lichen is a relatively reliable indicator of calcareous substrates, where it usually grows on bryophytes, plant debris or directly on soil. It often overgrows thalli of other lichens, such as cyanolichens. It may also grow on epiphytic bryophytes on nutrient-rich bark. Its typical habitats are crevices of natural sunlit and partially shaded rocky outcrops, but it can also occur in anthropogenic habitats (e.g. on walls). Agonimia tristicula is a widespread, locally common species in the temperate zone of the Northern hemisphere. In the Czech Republic, it occurs scattered from lowlands to mountains. It is usually one of the most abundant lichens in karst areas.

Ascomycota → Eurotiomycetes → Verrucariales → Verrucariaceae → Agonimia