Lichen are composite organisms. They contain fungal cells in addition to algal cells, or cyanobacteria. These cells have a symbiotic relationship, which means that they work together for survival.
This here is crustose lichen, and you can tell by it’s crusty appearance. Crustose lichen is one of the major groups that lichen can fall into. In this case, the organism is the only thing living on this boulder. Over time, it will break down the granite and eventually render it into soil.
This has been your daily nerdy tidbit.