Description: This rare, foliose, tuft-forming species has a thick, lumpy, brown-black, cushion-like thallus resembling the folds of the human brain. In the dry state, the ridges shrivel and become more flattened. Tiny granular, brownish isidia may be visible on the surface. It grows mainly in old woodland on deciduous trees such as hazel and oak. Discs are unknown in Ireland. It has a predominantly westerly distribution.

Key Identification Features:

• ‘Brain’ lichen has swollen lobes when wet, becoming ridged and wrinkled when dry. L. coralloideum differs in its pale, blue-grey, cylindrical, coralloid isidia which follow the ridges of the upper surface
• In oceanic woodlands (Counties Kerry, Galway, Clare, Mayo).

Original text submitted by Vince J. Giavarini

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

iNaturalist: Leptogium brebissonii at iNaturalist World Species Observations database.