Pseudothelomma ocellatum is characterized by a thick grey thallus and almost black soralia on its surface; apothecia are rare. Thus, it is one of the few calicioid lichens that reproduce mainly vegetatively. The species typically grows on fences and similar wooden constructions, mainly on horizontal surfaces of worked timber. It prefers slightly nutrient-enriched places. Considering natural substrates, it mainly grows on the wood of dry branches and trunks of Larix decidua and Pinus cembra in the subalpine zone in the Alps (Tibell 1976, Nimis et al. 2018). It is a boreal-montane species with slightly continental tendencies. The lichen is scattered in the Czech Republic, known exclusively from anthropogenic substrates. It currently occurs mainly in southern Bohemia and a few other localities.
Literature: Tibell L. (1976): The genus Thelomma. − Botaniska Notiser 129: 221 −249. Nimis P. L., Hafellner J., Roux C., Clerc P., Mayrhofer H., Martellos S. & Bilovitz P. O. (2018): The lichens of the Alps – an annotated checklist. − Mycokeys 31: 1–634. Halda J. P., Palice Z. & Peksa O. (2005): Tři pozoruhodné nálezy lišejníků z podhůří Orlických hor. – Orlické hory a Podorlicko 13: 317–319.
taxonomic classification:Ascomycota → Lecanoromycetes → Caliciales → Caliciaceae → Pseudothelomma
most frequented synonyms:Thelomma ocellatumRed List (Liška & Palice 2010):VU – vulnerable
Red List (Malíček 2023):C3 – endangered
Occurrence in the Czech Republic
All records: 26, confirmed 24. One click on a selected square displays particular record(s), including their source(s).