A taxonomically still unclear species of crustose cyanobacterial lichen, currently treated in a broad sense. Porocyphus rehmicus forms extensive, dark brown to grey-black, finely granular to areolate-rimose crusts, usually occurring in places with seepage or outflow of calcium-rich water. It often produces numerous pycnidia, which later develop into almost spherical perithecioid fruiting bodies – so-called pycnoascocarps – gradually opening on the surface of the thallus.
In the field, the species is difficult to distinguish from the similar lichen Lemmopsis arnoldiana, which usually forms flatter, biatorine apothecia. Both lichens can theoretically be separated based on their photobiont, ascospore size, and the ontogeny of their fruiting bodies, but in practice, specimens are often juvenile and sterile.
In the Czech Republic, P. rehmicus has been reported from the Křivoklát region, Prague, and the Bohemian and Moravian Karst, where it occurs on both volcanic and limestone rocks. It prefers warm and sunny habitats.
Literature: Malíček J. & Palice Z. (2025): Lišejníky přírodní památky Kalvárie v Motole v Praze. – Bryonora 75: 41–70.
taxonomic classification:Ascomycota → Lichinomycetes → Lichinales → Lichinaceae → Porocyphus
All records: 17, confirmed 16. One click on a selected square displays particular record(s), including their source(s).