Lichens : Lecanorales : RamalinaceaeLichens

Lecania rabenhorstii (Hepp) Arnold

Description: In this species, the non-pruinose, yellowy-grey thallus often forms circular patches on basic rocks or walls. The patches are heavily eroded and form archipelagos of scattered islands (areoles) like randomly shuffled Scrabble pieces. The pruinose orange-brown discs are restricted to the tops of the areoles (‘they sit on a pile’). The spores are one-septate. In Ireland, it occurs along the coast but appears rarer in the east.

Key Identification Features:

  • The thallus is circular and breaks as it expands giving an appearance of shuffled scrabble pieces
  • The orange-brown discs are restricted to the tops of the areoles.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Lecania rabenhorstii at iNaturalist World Species Observations database.

 Giavarini, Vince J., Simms, Michael J., & Davey, Simon, 2026. Lecania rabenhorstii. (Hepp) Arnold. [In] Lichen Ireland.
https://www.habitas.org.uk/lichenireland/species.php?item=39648. Accessed on 2026-11-12.