Description: This is one of only two filamentous lichens known to occur in Ireland. Both grow in deeply sheltered niches on siliceous rocks and boulders. The thallus of C. ebeneus is a narrow, black, brittle, cottony, strand-like filament surrounded by a net of fungal hyphae that en masse can resemble snagged, black sheep’s wool. Under the microscope (which is essential for separating the two filamentous species) each strand has its longitudinal hyphae rather jaggedly, unevenly or lumpily arranged. Upland Ireland.

Key Identification Features:

• Thallus: of strands, like pinches of black, cotton wool; grows associated with damp, sheltered, acid rock underhangs
• Cell hyphae wrinkly, arranged higgledy-piggledy; in Racodium, the cell hyphae have straight walls lining up in more orderly fashion.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Cystocoleus ebeneus at iNaturalist World Species Observations database.