THALLUS: very thin, smooth, whitish to pinkish or yellowish gray
APOTHECIA: to 3 mm; disc pale orange, epruinose; margin thick and smooth
CHEMISTRY: disc, margin, and parts of medulla C+ and KC+ red (gyrophoric and olivetoric acids)
Common Name: Smooth Saucer Lichen
Thin smooth whitish crust lichen with large thick-rimmed apothecia on deciduous trees.