English: A lichen - Baeomyces rufus. The lichen is shown here growing on a boulder of (locally abundant) red sandstone that was lying half-buried among grass on the moor.

The lichen's main body consists of a granular green crust. This species is sometimes found sterile (i.e. only the green crust is present); however, the specimen shown in this photograph is abundantly fertile, with numerous brown fruiting bodies on pale stalks, resembling little mushrooms; in fact, the green crust covered the entire visible surface of the rock, so that no bare sandstone was visible.

The habitat of this species is "shaded, damp situations, gravel, peat, acid rocks and soil, especially near water" [Frank S. Dobson, in "Lichens - An Illustrated Guide to the British and Irish Species"]; see https://www.geograph.org.uk/photo/1051534 for an example on peat. This area naturally has a very wet climate, and, although the land here slopes to the west, the presence of many small pools here (1091782) probably has the effect of reducing run-off, increasing moisture levels in the soil.