Galapagos Species Database

Thallus thin, inconspicuous, almost entirely embedded in the substrate, of the same color as the substrate or slightly darker, grayish to grayish white, or ochraceous; surface smooth, not pruinose; Apothecia immersed to prominent, lirellate; lirellae broad, short to ±elongate, sparsely branched; labia thick, broad, blackened, not covered by the thallus, initially prominent, but with age becoming excluded; disc expanded, flattened, blackened, typically ±covered by an inconspicuous farinose whitish pruina, often transversely fissured, becoming distinctly septate with age; exciple carbonized, the carbonization most prominent at the base and increasing in with age, typically including the subhymenium, lateral exciple less distinctly carbonized; hymenium hyaline, inspers, I– or I± weakly pale blue; ascospores pale gray, brownish with age, I+ reddish brown, (4)8 per ascus, narrowly oblong to fusiform, 23-45 x 6-12 µm, transversely septate, 7-12 celled. Chemistry: Traces of stictic acid; K+ yellow, P+ orange (reactions often very weak, check in the microscope or with TLC).

All, but one of the Galapagos specimens have a very thin thallus and spot tests reactions are therefore very weak, but the pruinose disc, and fissured lirellae that may become septate with age are diagnostic for this species.