Lichens : Lecanorales : ParmeliaceaeLichens

Usnea glabrescens (Nyl. ex Vain.) Vain.

Description: The ‘beard’ lichen U. glabrescens is a semi-pendulous lichen of willow swamp and marshy woodland. It is densely tufted near the blackened base and throws out little branched extensions that grow well beyond the main limit of the thallus. It only produces soralia, but these are distinct — rounded, regular and weakly impressed on the branches. In Ireland, the species has been recorded from Counties Clare, Galway and Londonderry; there are even earlier records from County Cork.

Key Identification Features:

  • Semi-pendulous ‘beard’ lichen, black and tufted near the base with some branches growing as extensions to the main thallus
  • The branches produce neatly rounded soralia containing only soredia; two of the three chemotypes are K+ yellow-red, a chemistry not shared by U. subfloridana.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Usnea glabrescens at iNaturalist World Species Observations database.

 Giavarini, Vince J., Simms, Michael J., & Davey, Simon, 2026. Usnea glabrescens. (Nyl. ex Vain.) Vain.. [In] Lichen Ireland.
https://www.habitas.org.uk/lichenireland/species.php?item=19144. Accessed on 2026-11-12.