On standing stones in the Cotswolds/Chilterns area.
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.
I don't know Caloplaca teicholyta very well either, but I think it's right. To those in the south east it is locally a common fungus, but like you I live well outside its tightly defined geographical range and I don't know its habits yet.
I am not sure it is parasitised, but I see what you mean; it does look unhealthy. However, I don't think Diplotomma murorum is involved.
Thank you Alan.
I kicked myself for lack of K/C to test it with but I was out for the day with my daughter and lichen bimbling had been banned!
Lat/Lng: 51.8, -1.4
OS grid ref: SP4517