[3] Abramo Bartolommeo Massalongo transferred the taxon to the genus Pyrenodesmia in 1852, a genus he circumscribed to include a group of four species (P. agardhiana, P. chalybaea, P. olivacea, and P. variabilis), all of which lacked anthraquinones (a class of secondary metabolites common in the family Teloschistaceae), and contained instead the insoluble lichen pigment Sedifolia-gray.

[6] Pyrenodesmia includes members of the former Caloplaca variabilis species complex; the uniting chemical characteristic of this group of lichens were shown to be phylogenetically distinct.

These apothecia are either sparsely scattered or densely crowded on the thallus surface, and they are sessile, meaning they are attached directly without a stalk.

The paraphyses, which are slender filament-like structures in the hymenium (spore-producing layer), broaden and become stouter towards their tips, reaching about 3 μm in diameter.

They are polarilocular, with a septum (an internal dividing partition) that is 2–3 μm wide and can sometimes be as long as a third of the total length of the spore.

[5] This species is widespread throughout England and Wales, including the English Midlands, with a distribution that extends sporadically to Scotland and Ireland.