The southwestern Baltic Sea–Kattegat area: : a hotspot for the lichen genus Xanthoria s.l.

More than 3500 samples of lichen genus Xanthoria s.l. were collected at 135 localities in the Baltic Sea–Kattegat area during 2022–2025. Of these, 177 were selected for phylogenetic analyses using ITS and mt-sequences. The phylogenetic tree of Xanthoria s.str. reveals 24 clades possibly corresponding to species, six of which are described, i. e. X. calcicola, X. coomae, X. ectaneoides, X. pedersenii, X. pylyporlykii and X. wennergrenii. The studied area is undoubtedly a hotspot for the genus Xanthoria s.l. and the number of species is much higher than expected. Rusavskia drevlyanica and Xanthoria coomae are confirmed for the first time from the studied area. A close relationship between Rusavskia drevlyanica and Zeroviella esfahanensis is revealed.