Mosses recognized as glacial relicts from their postglacial distribution in Poland

Abstract

Some glacial relict (mosses) have survived from the Ice Age up to the present time in specific, long-lasting habitats. Mires are one of the most common ecosystems in which they are present. In this paper the past distribution of eight species of such peat-forming mosses in Poland in the past is discussed. The distribution and dates of previously published moss finds in Poland have been mapped. In almost every case the largest number of places where they were found was in northern, or more precisely northeast Poland. A significant difference in the number of known find sites for individual species and many sites of unknown age were found. The rarest moss was definitely Cinclidium stygium and the most frequent was Meesia triquetra. Data on the distribution of mosses in the Late Glacial and Holocene proved to be scarcer than expected. Only a few sites were found where the occurrence of species such as Meesia triquetra, Calliergon giganteum, Tomentypnum nitens, Pseudocalliergon trifarium, Helodium blandowii and Scorpidium scorpioides was fairly continuous for this period. Therefore, the status of these mosses as glacial relicts seems to merit some thought. Certainly, there is a further need for high resolution research on bryophyte macrofossils, combined with accurate dating.