Some missing data probably will never permit to identify the lichen in this observation, but based on what I can see I will bet on Xanthoparmelia mougeotii, even taking into account that I not very familiar with the genus Xanthoparmelia. At least I think that it matches the short description given in the reference for that species. The missing data are, for instance, details about the underside though the photos seem to indicate a dark color and the existence of rhizines. Other missing data are the chemical reactions on medulla. Even the data from the upper cortex are not complete, the C reaction is missing and I could not find it in the photos I took (which probably means C-). Note that the KC reaction exhibit some orange/red tones superimposed to the dark cortex at the place were it was made.