photo of a crust-forming lichen covering a young ash tree trunk from Argyll. The surface is cracked and contains many partially immersed, dark, rounded perithecia.

mmm... peppercorn sauce. Or maybe just a lichen. There's a tiny hemipteran nymph hiding in these photos, too.
I think the lichen is Pyrenula macrospora.

#lichen #pyrenula #hemiptera #fraxinus #argyll #scotland #uk #naturephotography