Lasallia papulosa
Lasalia papulosa photo by Bob Klips
Lasallia papulosa wet and dry photo by Ray Showman
DIAGNOSTIC FEATURES: Central attachment; blistered thallus; undersurface pale brown, pitted; no rhizines except centrally; compare with L. pensylvanica with undersurface uniformly black, papillate-areolate.
ECOLOGY: This Appalachian species is fairly common in unglaciated Ohio; usually found on sandstone, very rarely on soil or bark adjacent to colonies on rock.