Galapagos Species Database

Thallus thin, continuous, either forming a thin film encrusting bryophytes and plant debris, or granular to granular verrucose, over rock; surface smooth and shiny, pale creamy white to brownish, not pruinose; Apothecia typically distinctly and conspicuously stalked, rarely sessile, lirellate; lirellae very broad and short, never branched (melaspileoid); labia thick, entire, black, only basally ± covered by a thin thallus layer; disc concealed, a thin slit; exciple completely carbonized, carbonization extending below the hymenium; hymenium hyaline, clear (not inspers); ascospores hyaline to pale gray, brownish with age, I+ bluish violet, 8 per ascus, large, narrowly oblong to fusiform, 22-27 x (80)130-210 µm, transversely septate, (11)16-22 celled Chemistry: Norstictic acid, K+ orange (red crystals), P+ yellow, C-. Etymology: The name refers to the distinctly stalked lirellae.

This species is similar to other species of the G. nuda group but contains norstictic acid and thus reacts K+ orange (red crystals). Only one other species in that group, G. emersa, has norstictic acid, and G. pedunculata also has by far the longest ascospores in that group. The species is superficially similar to G. cleistomma from which it can reliably be distinguished by the more distinctly blackened lirellae, typically not covered by the thallus and much longer, transversely septate instead of muriform ascospores. In the Galapagos, G. cleistomma has been found encrusting bryophytes and plant debris, whereas G. pedunculata appears to prefer rock substrates.