Lichens in the vicinity of Colesdalen, one of the “hot spots” of the Svalbard archipelago

This study summarizes the lichen diversity in the Colesdalen area of Svalbard, where a total of 234 species are known. Notably, 112 of these lichen species are reported for the first time in this region. Among them, the newly recorded species are Arthonia granitophila, Ionaspis obtecta, Micarea denigrata, Poeltinula interjecta, Rhizocarpon infernulum, R. subgeminatum, Rinodina mniaroea var. cinnamomea, Sagedia zonata, Sarcogyne lapponica, which are new to Svalbard. Furthermore, Arthonia granitophila and Poeltinula interjecta are documented for the first time in the Arctic. Additionally, 27 species have been identified as new to Nordenskiöld Land (Central Spitsbergen). The ecological conditions of the Colesdalen area, including its unique microhabitats and sub-strate availability, significantly influence the lichen biodiversity and site-dependent vege-tation composition. This research contributes to the knowledge of local biodiversity of lichens and highlights how certain species can thrive beyond their typical ranges due to specific environmental factors – substrate, altitude, anthropogenic impact, distance from glaciers, humidity. Approximately half of the identified species are known only from the study area or from a few locations on Svalbard. This highlights the specificity of the natural conditions of the study area as well as the complex interactions between natural ecosystems and human-modified environments, emphasizing the importance of further study and documentation of Arctic lichens.