Ovstedal, D. O., & Smith, R. L. (2001). Lichens of Antarctica and South Georgia: a guide to their identification and ecology. Cambridge University Press.

Thallus white to pale buff, crustose to subeffigurate, areolate to 5 cm diam.  Apothecia black, sessile, to 1 mm diam, when young with thin, true margin; when old margin excluded.  Hymenium 90-100 µm high, upper part green-brown.  Exciple and hypothecium black.  Asci 8-spored.  Ascospores halonate, elliptic, 15-24 X 10-14 um.  Medulla K/I-.

TLC:  Negative.

Ecology:  On calcareous rock, with Lecanora nylanderiana and Thelidium austro-atlanticus.  50-100 m.

Distribution:  Bipolar.  North and Central Europe, North America.  Antarctic South Orkney Is, South Shetland Is, Antarctic Peninsula.

Literature:  Hertel (1984, 1989).