Published online by Cambridge University Press: 09 December 2019
The first detailed survey is presented of a recently discovered population of Erioderma pedicellatum, a globally rare lichen, in the primeval spruce forests of the Kamchatka Peninsula, Russia. Three subpopulations are described, located in the Levaya Schapina River basin, in the Kimitina River basin, and on the slopes of the extinct volcano, Nikolka. In total, we observed 1894 thalli on 167 Yezo spruce trunks. In Kamchatka, E. pedicellatum occurs exclusively on bark-covered spruce twigs of mainly young and dwarf-stressed older trees. We discovered a high number of juvenile thalli, which suggests that this population is reproducing. However, its habitat is declining because spruce forests in the region are the target of industrial clear-cutting and there is a high incidence of forest fires. Over the next 60 years, which corresponds to three generations of E. pedicellatum, we infer that continued habitat loss will induce a 48% decline in these lichen populations. As a result of our analyses, the Asian population is classified as ‘Vulnerable’, based on IUCN Red List criteria.