Lišejníky chráněných území Ralsko a Vranovské skály (severní Čechy)

The diversity of lichenized fungi was explored in two close protected areas, Ralsko and Vranovské skály, during several field excursions in 2017 and 2018. We present a list of 298 species, including 272 recently recorded taxa: 223 species from Ralsko and 137 species from Vranovské skály. The Ralsko Nature Reserve protects ecosystems of tephrite rocks and boulder screes, a castle ruin and old-growth scree woodlands. Rare species are mostly represented by montane epilithic lichens, for example Acarospora insolata, Melanelia panniformis, Fuscidea recensa, Lecanactis dilleniana, Lecanora cenisia f. soredians, Ophioparma ventosa, Porpidia cinereoatra, Stereocaulon pileatum, S. vesuvianum var. symphycheileoides, Umbilicaria hyperborea and U. subglabra. Lecidea phaeops and Rinodina teichophila, which are so far known from a single locality in the Czech Republic, were recorded on the screes and in the area of the castle ruin, respectively. The woodlands, which were strongly influenced by acid rain in the past, harboured several typical old-growth forest species such as Bacidia vermifera, Calicium viride, Chaenotheca brachypoda, C. chlorella and Sclerophora peronella. The bedrock of the Vranovské skály Nature Monument is made up of a mixture of acidic and calcareous sandstone rocks. The locality is rich in various crustose microlichens, many of which have only rarely been reported from the Czech Republic. Acrocordia conoidea, Arthonia calcicola, Bacidia arceutina, Bacidina egenula, Caloplaca albolutescens, C. dichroa, C. interfulgens, Diplotomma canescens, Lecania coeruleorubella, L. hutchinsiae, L. sylvestris, Leptogium plicatile and Verrucaria compacta represent the most valuable records. Sixty-one lichen species have been recorded historically, but 24 of them have not been confirmed recently. Most of them are rare epiphytes (Lobaria pulmonaria, Nephroma parile, Peltigera collina and several microlichens) and some are generally non-epiphytic lichens with cyanobacteria in the thallus or in the cephalodia (Peltigera horizontalis, P. polydactylon, Stereocaulon paschale, S. tomentosum and Vahliella leucophaea). The current absence of these species was most probably caused by the acidification of their substrates by sulphur dioxide air pollution in the 20th century.