Rhizocarpon ridescens a Verrucaria ochrostoma – dva nové druhy lišejníků pro Českou republiku

Rhizocarpon ridescens (Nyl.) Zahlbr. and Verrucaria ochrostoma (Borrer ex Leight.) Trevis. are reported for the first time from the Czech Republic. Both taxa were collected in the Krušné hory Mts (Erzgebirge). Rhizocarpon ridescens was found on a copper spoil heap at Mt Tisovec and Verrucaria ochrostoma on a calcium-enriched quartzitic rock in the nature reserve Vysoký kámen. Site details, known distribution and diagnostic characters are described.