DESMIDS FROM A PEAT-BOG IN THE NORTHERN APENNINES (ITALY)

This study is the first on desmids in the Apennine peat-bogs, which ar e relicts of the great Quaternary glaciations. In a small peat-bog ric h in Sphagnum mosses, at an altitude of 1280 m as.l. in the northern A pennines, 45 species and varieties have been found, some of which new or very rare for the Italian desmid flora. Using autoecological analys is, all these desmids were subdivided into five groups, differing abov e all in their pH requirements. There is a clear prevalence of acidoph ilous and acidobiontic species, many of them very characteristic of pe at-bogs, that confirms the high level of selectivity of these environm ents. Comparison of the biotope examined here with other similar ones in, the Alps, showed that the greatest degree of similarity in desmid flora is found with those peat-bogs where the same type of phanerogami c vegetation is dominant; and this independently, to a great extent, o f the abundance of Sphagnum mosses.