Description: This is a mildly calcifuge lichen of heaths and moors where it grows on peaty soils and around tree stumps. The thallus is coarsely granular, brown, becoming yellower when wetted. The brown-black convex discs are often clustered together like piles of miniaturised animal droppings. In Ireland, most modern record from coastal County Mayo.

Key Identification Features:

• Forms coarse brown granules (testing C-) over peaty soil surfaces, yellow when wet, but avoids the most acid areas
• Discs flat to convex (0.2–0.5mm diam.); in clusters.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Placynthiella oligotropha at iNaturalist World Species Observations database.