Distribution data originating from earlier herbarium collections and recent biodiversity
records form the basis of distribution analyses in lichen species with different ecological
requirements, where the records allowed comparisons or showed clear trends. As the
occurrences of lichens are strongly correlated to background environmental conditions
(e.g., air pollution, global warming), confirmed by Wirth’s ecological indicator values,
the analysis of distribution types has a great value for bioindication and the establishment
of current and future climatic and pollution situations. Five distribution types were
introduced—presented by characteristic examples (13)—according to lichen distribution
maps prepared in different periods of time (representing changing environmental conditions):
(1) species of decreasing occurrences by time (e.g., Lobaria pulmonaria, Menegazzia
terebrata, suboceanic, acidic pollution sensitive species), (2) species with no or
few former records but with increasing occurrences in recent decades (e.g., Flavoparmelia
soredians, Hyperphyscia adglutinata, Solenopsora candicans, sub-Mediterranean species),
(3) species with increasing and then (from c. 2000) decreasing occurrences (e.g.,
Scoliciosporum chlorococcum, Straminella conizaeoides, acidofrequent species), (4)
species with widely increasing occurrences in recent decades (e.g., Physcia aipolioides,
Piccolia ochrophora, Xanthoria parietina, nitrofrequent species), and (5) species
with rapidly increasing occurrences (e.g., Absconditella lignicola, Coenogonium pineti,
Evernia divaricata, rapidly spreading species). The proposed distribution types of
lichen species may be applied to wider regions (the European or the global level).
