Pycnora

Pycnora is a small genus of lichen-forming fungi in the monotypic family Pycnoraceae. The genus was established in 2001 by the Austrian lichenologist Josef Hafellner, who named it by combining references to its conspicuous black reproductive structures and its relationship to the lichen genus Lecanora. These wood-dwelling lichens form thin grey crusts on the smooth surfaces of dead wood in cool northern and mountain forests, where they colonise fallen tree trunks and branches that have lost their bark. The genus contains three species and is distinguished by its readily visible black fruiting bodies and the presence of alectorialic acid, a secondary metabolite not found in similar-looking lichens.

Taxonomy

The three species now placed in Pycnora were long shuttled between other crustose genera. Lecidea xanthococca (1826) and the later Lecidea praestabilis and Lecidea xanthococca subsp. sorophora were all moved to Hypocenomyce during the mid-twentieth century, largely for want of a better classification. Yet their asci do not match the Bacidia-type architecture that defines Hypocenomyce; instead they bear the Lecanora-type euamyloid dome. Recognising this mismatch—as well as a distinct chemistry dominated by alectorialic acid derivatives—Josef Hafellner segregated the group in 1984, erecting the new genus Pycnora within the order Lecanorales and designating Pycnora xanthococca as its type species. The generic name combines "pycnidium", referring to the conspicuous asexual fruiting bodies, with "-nora" to signal kinship with Lecanora.