Description: When in and around those parts of the country with a history of old mine workings, then this species should be looked for as it is entirely dependent on the presence of iron minerals. Vertical walls and the sides of old ore dumps are the most productive habitats. Here it forms brown scurfy patches, usually without discs. It can be a rather dreary thing. Sometimes it can grow to become quite extensive forming large spreading patches. The medulla turns K+ yellow; Pd+ orange. In Ireland, it has been recorded from Connemara.

Key Identification Features:

• Dependent on old mine workings and iron minerals
• Thallus brown, scurfy, spreading; medulla K+ yellow; Pd+ orange.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Rhizocarpon furfurosum at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Rhizocarpon furfurosum at iNaturalist World Species Observations database.