Description: This taxon, like its relative M. confusa (described elsewhere), is a close ally of epiphytic Arthopyrenia species and therefore a member of the ‘bark pimple’ tribe of lichens. All Mycomicrothelia differ from Arthopyrenia in their brown-coloured spores. M. atlantica (like M. confuse) has an almost invisible fringe of cells around the conical discs (perithecia). It is readily distinguished by the silvery-grey thallus, smaller spores (13.5–16µm long), presence of pycnidia between the discs and more heavily shaded hazel woodland habitat.

Key Identification Features:

• Thallus silver-grey, on smooth, deeply-shaded hazel bark
• Spores small (<16µm long) with a spotting of pycnidia between the discs.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Mycomicrothelia atlantica at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Mycomicrothelia atlantica at iNaturalist World Species Observations database.