Galapagos Species Database

Thallus thin, continuous to rimose, lead gray to whitish gray; surface smooth, not pruinose; Apothecia prominent to sessile, lirellate; lirellae broad, elongate, moderately to sparsely branched; labia thick, broad, blackened, soon distinctly striate, almost entirely covered by a smooth thallus layer that may in parts erode with age; disc concealed, a thin slit; exciple completely carbonized, carbonization extending below the hymenium; hymenium hyaline, clear (not inspers), I–; ascospores hyaline, I+ bluish violet, 4-6 per ascus, narrowly oblong to fusiform, 80-132 x 12-16 µm, mostly transversely septate, but terminally becoming muriform, with 18-23 transversal septa, terminal cells with 1-2 septa. Chemistry: No substances found; all spot tests negative.

Care should be taken to examine the lirellae of specimens closely for remnants of yellow pruina to avoid confusion of the species with G. flavominiata (differences see there).