Search the website

Lichen: Usnea subfloridana

« Back
800-general-view

Usneas subfloridana, Ireland's most common Usnea.

800-closeup-of-thallus

Close up of Usnea subfloridana showing developing apothecia.

Close up of the apothecia. Few occur on Usnea subfloridana.

Close up of the apothecia. Few occur on Usnea subfloridana.

Usnea subfloridana: section through the main stem showing the medulla and cortex.

Usnea subfloridana: section through the main stem showing the medulla and cortex.Note green photobiont layer.

Usnea subfloridana Vice county distribution.

Usnea subfloridana Vice county distribution.

Name: Usnea subfloridana Stirt.

Pronunciation: Usnea subfloridana

Popular Name: Old man’s beard. Body Type: Fruticose

Conservation Evaluation: Least Concern

General Description: Bushy, pendulous lichen with colours in the grey-green to yellow-green range, with a distinctive blackened base with annular rings or cracks. The branches are cylindrical and tapered (no flattening).  The side branches are not narrowed where they attach to the trunk (they are in some species).  The trunk and branches are covered in patches of soredia or isidia. Apothecia are rare and when present there are very few (maybe three on a specimen).  Some specimens may consist of just a single stem and a few side branches. This divergent range of types (bushy to simple stems) makes Usnea difficult to identify.

Chemical Tests: K + yellow instantly, Pd + medulla turns yellow-orange.

Nature Notes: This is the most common Usnea in Ireland and also the most resistant to air pollution.

Vice County distribution map of Acarospora fuscata: See Map

Link: Map this species on the Lichen Survey

Other species recorded in Ireland

  • Usnea articulata (L.) Hoffm.
  • Usnea ceratina Ach.
  • Usnea cornuta Körb.
  • Usnea esperantiana P.Clerc
  • Usnea filipendula Stirt.
  • Usnea flammea Stirt.
  • Usnea florida (L.) F.H.Wigg.
  • Usnea fragilescens Hav. ex Lynge [38]
  • Usnea fragilescens var. mollis (Vain.) Clerc
  • Usnea fulvoreagens (Räsänen) Räsänen
  • Usnea glabrescens (Nyl. ex Vain.) Vain.
  • Usnea hirta (L.) F.H.Wigg.
  • Usnea rubicunda Stirt.
  • Usnea wasmuthii Räsänen
  • Usnea wirthii P.Clerc

Text and images © Paul Whelan, 2009.