This is the exact same lichen as the one pictured here (http://bit.ly/qkJhIe), but lit differently (from the left). I'm posting this one as a contrast to demonstrate the importance of lighting in lichen photography. A circular brown foliose lichen with folds growing on a pinkish rock. The lichen has numerous black circles (probably apothecia) on its thallus. My best guess is that this is _Umbilicaria phaea_. This lichen was found in Vasquez Rocks County Park in Los Angeles County.