United States, Arizona, Coconino, Cave Springs, Red Rock Ranger District, Coconino National Forest
34.996509 -111.741405
UTM 12 S 0432342 3872907
1676 meters (5497ft)
NNW facing llimestone rock face, heavy shade from tree overstory, seasonal seepage occurs on the rock face, Ponderosa Pine Woodland
on rock
Placynthium nigrum
thallus foliose; Lobes discrete, irregularly rounded, concave and ascending at the end of the lobes; rhizome visible from above; upper surface gray to gray-brown, sorediate; soredia granular to isidioid; lower surface black, rhizines numerous; apothecia not seen; all spot tests negative