here’s a picture from the stubai alps, taken recently near oberiss in tirol. it shows a mosaic of crustose lichens, fighting for space on silicate rock.
lichen identification can be very difficult, even for specialists, but there’s one very easy to identify species prevalent in the picture: rhizocarpon geographicum is the greenish-yellow lichen with black dots (fruiting bodies), lightly resembling a map. in the lower right of the picture, there’s umbilicaria cylindrica (grey thallus, with black fringe). other lichens are believed to belong to the lecidea, lecanora, fuscidea and/or lecidella genera.