The lichen-forming fungi of the Xanthoparmelia pulla group (Parmeliaceae, Ascomycota) in Poland

The paper presents the results of studies of Xanthoparmelia pulla group in Poland. The morphological and chemical analysis of herbarium materials confirmed the presence of four species of this group reported from Poland before. The study however, revealed considerable changes it the partiuclular species distribution. X. verruculifera, so far considered the most endangered species in the country, turned out to be the most frequent taxon. X. loxodes, regarded as common, has much less known localities than previously thought. This species was usually confused with X. verruculifera. Xanthoparmelia pulla is the rarest species and should be considered critically endangered in Poland. Most specimens of X. pulla collected in the country belong to X. delisei, which so far had only two historical records in Poland. All these taxa are characterized in terms of morphology, the content of secondary metabolites, ecology and distribution.