Description: This is one of only a few lichen species that appear to thrive on small pebbly rock fragments lying on the disintegrating tops of limestone outcrops and cliffs. The grey, scurfy thallus has no lichen substances but the prominent brown to black discs, which become convex through exclusion of the rim, make them instantly identifiable. The hymenium of the disc contains tiny oil droplets; spores broad with a thick, pigmented band dominating the centre. In Ireland, the species is very rare.

Key Identification Features:

• Thallus grey, scurfy; discs common, sitting on the surface, rim becoming excluded with age
• Hymenium with oil droplets; spores barrel-shaped with thick, dark banded septum.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Rinodina bischoffii at iNaturalist World Species Observations database.