White lichen approx. 3cm diameter, tighly adherent to rock. Some black (?) reproductive bodies. Mainly sunny aspect, on horizontal surface.
Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
Just to confirm, no Lecidea grisella in the photograph.
Additional to the list above, there is at least one small colony of Rinodina oleae (= R. gennarii), a cluster of minute, white-rimmed apothecia on a tiny, green-grey crust.
Lat/Lng: 49.18775, -2.19321
OS grid ref: S^860208