U.S.A., Colorado, Boulder, West base of Steamboat Mountain, foothills of Front Range 2 miles N.W. of Lyons.
1900 meters
1900 m.
Abundant on north face of cliffs above stream.
Plants brown, polyphyllous, extremely fragile and tightly attached to rock; underside of thallus coarsely papillose, usually dark; thallus pruinose only in region of umbo. Substrate: saxicolous.