I gathered no fewer than four separate samples of this species this day, thinking all four were different at the time I collected them. This is a combination of the notes from all four observations:
Endolithic crust, on exposed granite, especially road cuts or other “young” or flaking/weathering surfaces.
MEDULLA: whitish, K/I-
APOTHECIA: black, lecideine, clustered in lines along cracks
DISC: black, flat to flexuous when crowded, epruinose to conspicuously white-pruinose, 1-2 mm wide
RIM: prominant to barely raised, black, shiny, smooth, even
EPIHYMENIUM: dark brown to slightly greenish or blue-greenish, K-, POL-
HYMENIUM: clear to brownish to bluish-greenish, POL-
EXCIPLE: black to very dark brown outer layer grading into brown to reddish-brown, K-, C-, POL-
PARAPHYSES: clear, nonseptate, expanded gently to rounded tips, some branched, strongly conglutinated
SPORES: 8 per ascus, simple, clear, elliptical to oblong, smooth, around 10-12 × 3 µm
Note that the size is somewhat variable, and the amount of pruina is extremely variable. Microscopically, the precise color of the hymenium and epihymenium also seems variable, with the greenish or bluish-greenish tint being either absent completely or almost throughout the hymenium.
Otherwise, the macroscopic characteristic that unites all of these seems to be its crowded or clustered habit, generally following microfissures in the rocks, the apothecia often pressing up against each other in lines. It is also generally larger than its look-alikes (such as other Lecidea spp. and a few Sarcogyne spp.).
|User’s votes are weighted by their contribution to the site (log10 contribution). In addition, the user who created the observation gets an extra vote.|
|I’d Call It That||3.0||6.45||1||(jason)|
sum(score * weight) /
(total weight + 1)