Description: This crustose lichen has cyanobacteria (blue-green algae) fastened into its structure which makes it gelatinous when wet, thus capable of surviving in aquatic or semi-aquatic environments. Look for the black, approx. 2cm-diam. thallus, on boulders, around the edges of loughs during the middle of the year, when the discs with a pore-like opening, shrivel to resemble the pimpled surface of a table-tennis bat. It is very rare in Ireland.

Key Identification Features:

• Cannot be confused with other Porocyphus species; thallus crustose, brown to black, mostly smooth
• Discs in tight, erect pimple-like clusters, black with pore-like opening at the tip, through which the paler contents may be glimpsed.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Porocyphus coccodes at iNaturalist World Species Observations database.