Article

The aim of this project was to assess the importance of nearly pristine forests in maintaining lichen diversity. We studied exhaustively the biodiversity of lichens in the Natural Reserve of Muniellos (Spain, SW-Asturias), 5542 hectares, an area important for conservation -being included in the UNESCO-MAB reserves network. Besides their ecological value, these thriving elements and their photobionts can be used as bioindicators for Conservation Biology. The survey has been carried out together with vascular-plant phytosociologists and bryologists. Model plots in almost 70 locations enabled us to demonstrate the extraordinary wealth of the lichen flora in these mountains. Saxicolous lichens, on an almost total dominance of siliceous Palaeozoic substrata, were practically unexplored in the Cantabrian Relief of the Iberian Peninsula. The ancient woods constitute critical habitats for maintaining a large number of species threatened by human activities. As “quality” bioindicators, lichens show that there are no nitrophytic habitats in the Reserve. We have identified a total of 502 taxa, 474 being Lichens and 28 lichenicolous Fungi. The best represented genera are Cladonia (47), Lecanora (24), Pertusaria (19), Rhizocarpon (18), Micarea (12), Peltigera (11), Usnea (11), Fuscidea (9), Ochrolechia (9) or Epigloea (7). Many species are rare or unknown in Europe, i.e. Epigloea renitens, Gyalideopsis calabrica, Cystobacidium hypogymniicola, Rhizocarpon caesium, Porpidia flavicunda, etc. Many of these taxa are considered rare or as sensitive to small environmental changes, while they are relatively abundant in Muniellos.