Lichens : Lecideales : LecideaceaeLichens

Lecidoma demissum (Rutstr.) Gotth.Schneid. & Hertel

Description: Extinct in Ireland since 1884 (County Down), this lichen is best known by its resemblance to small soily ‘cow pats’. It grows on acid, peaty gravel soils on mountain tracks and ridges and is easily missed. Discs are common, convex and red-brown to brown. They grow up to 1mm diam. It once grew in the Wicklow Mountains and should be searched for there again.

Key Identification Features:

  • Thallus brown to brown-grey scattered with clusters of red-brown discs — resembling a small ‘cow pat’
  • On gravelly, acid mountain soils (usually above 500m).

Original text submitted by Vince J. Giavarini

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

iNaturalist: Lecidoma demissum at iNaturalist World Species Observations database.

 Giavarini, Vince J., Simms, Michael J., & Davey, Simon, 2026. Lecidoma demissum. (Rutstr.) Gotth.Schneid. & Hertel. [In] Lichen Ireland.
https://www.habitas.org.uk/lichenireland/species.php?item=18750. Accessed on 2026-11-12.