Description: The blackish thallus of this lichen is microscopically scaly and mixed with a thin smear of cyanobacteria. Though the tall discs (perithecia) are slightly immersed they form prominent structures with cylindrical algal cells and eight-spored asci. In Ireland, it grows on limestone near to where a stream emerges. It is tolerant of damp situations by watercourses, but generally avoids the most acid stream beds.

Key Identification Features:

• Blackish, roughened thallus; grows in the amphibious zone of rivers and streams
• Prominent perithecia containing eight-spored asci and cylindrical algae.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Nesothele succedens at iNaturalist World Species Observations database.