Varicellaria hemisphaerica is characterized by a silver-grey thallus, sometimes even blueish, large hemispherical soralia and the presence of lecanoric acid (C+ red). It usually forms well-delimited circular thalli. They might be confused with Ochrolecia androgyna when young.
It grows on the bark of older trees, mainly beeches, sycamores and oaks. It prefers old forests at various elevations, but in the Czech Republic it mainly grows in sub-montane and montane areas. In central Europe, it is scattered in naturally forested areas. In the Czech Republic, majority of the records comes from forest reservations, so it appears to be a good indicator of well-preserved continual forests.
taxonomic classification:Ascomycota → Lecanoromycetes → Pertusariales → Ochrolechiaceae → Varicellaria
most frequented synonyms:Pertusaria hemisphaericaRed List (Liška & Palice 2010):EN – endangered
Occurrence in the Czech Republic
All records: 81, confirmed 79. One click on a selected square displays particular record(s), including their source(s).