Hi everyone, I need some help, please. Being a chemist I am a few blocks out with identifying this lichen growing on tree bark. The upper surface is grey, the lower surface brown. It is quite prolific in Pretoria and the neighbouring Northwest Province. Unfortunately I could not get hold of a specialist locally, so I am bothering you :) Thanx!
Yes, I'm stymied as well. Too many things missing from the photograph, particularly the underside of the thallus and any reproductive structures. I compared it with lichens in the Lichens of North America book, and thought that there were at least a dozen things it resembled.
