Description: The thallus of this species is a pale grey, scurfy crust. The spherical discs (perithecia) are buried in deep pits in limestone so need to be excavated with the tip of a razor blade before viewing under the microscope. The colourless spores are grouped together in sacs (asci) of eight. Cylindrical algal cells are present within the discs. It is a species of hard limestones, usually at exposed sites but in County Clare, at the only locality for the species in Ireland, it was growing in a more sheltered situation.

Key Identification Features:

• Tiny perithecia buried deep in pits in limestone rock
• The unprotected discs contain cylindrical algae and eight-spored asci.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Staurothele bacilligera at iNaturalist World Species Observations database.