Galapagos Species Database

Thallus thin, inconspicuous, almost entirely embedded in the substrate, of the same color as the substrate or slightly darker, more yellowish orange; surface smooth, not pruinose; Apothecia immersed, lirellate, initially ±fissurine; lirellae thin, elongate, moderately to sparsely branched; labia thin, narrow, surrounded by a striate thalline margin composed of several papery thallus layers; disc initially fissurine, but soon expanded, immersed, flattened, blackened, and ±covered by farinose whitish pruina; exciple thin, apically carbonized with aeruginose pigment, carbonization laterally fading, basally unpigmented; hymenium hyaline, clear (not inspers), I–; ascospores pale gray, soon brown, I+ reddish brown, 4(-6) per ascus, ellipsoid to broadly oblong, 17-23 x 7-9 µm, transversely septate, (3)4-6 celled. Chemistry: No substances found; all spot tests negative. Etymology: The name refers to the striate thalline margins of the lirellae.

The species is very distinct because of its conspicuously striate thalline margin composed of several thin layers. In young apothecia these thallus layers cover the disc almost entirely and these lirellae then almost appear fissurine. Phaeographis subdividens (Leight.) Müll. Arg. known from India, Sri Lanka, and the Solomon Islands is anatomically similar, but its discs are not pruinose, the asci are 8-spored, the exciple pigmentation is brown, and the thallus margins are not distinctly striate.