A revision of the lichen genus Platismatia (Parmeliaceae) in Russia, with a key to the species
The paper presents the results of the study on Platismatia species in Russia. The genus Platismatia counts 11 species, distributed mainly in the Pacific region, with some endemics of western North America and northeastern Asia. Six species were known from Russia by the beginning of our studies, but a revision of the herbarium collections showed that three species (P. erosa, P. herrei, and P. lacunosa) were reported erroneously. Based on morphological and chemotaxonomical (HPTLC) examination of the herbarium collections and our own material, as well as the study of relevant literature, four species of Platismatia are here accepted for Russia: P. glauca, P. interrupta, P. lacunosa, and P. norvegica. Platismatia lacunosa is reported here as a new for Russia from the Commander Islands. The distribution of P. glauca and P. interrupta is clarified. A key to all species of the genus reported from Russia and brief descriptions of the Russian species are presented.