So, "immaculate" means spotless, and this one has a spotted upper surface (with maculae). Parmelia has what looks like a network of whitish cracks on the upper surface, and (in the west) no apothecia.
JJ Johnson
2015-01-00
Sat Jan 10 2015 12:42:45 GMT-0800 (PST)
United States of America, California, El Corte de Madera Creek Open Space Preserve