A note on the history, morphology, and distribution ecology of the boreal felt lichen, Erioderma pedicellatum (Hue) in the northern hemisphere.

The complex history of discovery, population declines, extinctions, and rediscoveries of the boreal felt lichen in the northern hemisphere is examined here for the first time in 124 years following its detection in Canada. We also present evidence of the presence of two distinct morphological forms of the boreal felt lichen. The southern form is in Atlantic Canada and is characterized by a darker, hairless exciple, shorter spores, and a pruina. The northern form occurs in Norway, Alaska, Kamchatka, Quebec, Labrador and northwestern Newfoundland. Although the morphology of the northern form seems identical across North America, Europe, and Asia, the community ecology for patterns for the lichen in Quebec and Labrador deviate from the other subpopulations. New genomic analyses will be required to untangle the population structure of the boreal felt lichen. Since the last IUCN assessment, the number of mature individuals has increased 42-fold, and its geographic distribution has expanded to include western north America, Asia, and the boreal mainland of Canada. This significant increase in population, combined with extensive un-surveyed suitable habitat, and the metapopulation dynamics of this lichen, will make future assessments challenging and will require more field research.