• Parmelinopsis horrescens (Taylor) Elix & Hale
Parmelinopsis horrescens
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Known only from the Killarney area of County Kerry P. horrescens is a small (to 4cm diam.), rosette-forming, foliose species. The frequently overlapping lobes have a grey-white upper surface sprinkled with coral-like or flattened isidia mixed with black, hair-like cilia which make it unmistakable in the field. The medulla is C-. It does best on acid-barked broadleaved trees and shrubs such as oak, alder and leggy gorse near humid woodland sites and along river valleys. In Ireland, it has spread to lakeside boulders.

Key characteristics

  • The mixture of isidia and cilia on the lobes distinguishes it immediately from P. minarum (which is also medulla C+ red) and the much larger Parmotrema crinitum which lacks isidia altogether
  • Acidic bark near old, humid woodland habitats are the conditions most favoured.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Parmelinopsis horrescens (Taylor) Elix & Hale. [In] LichenIreland. Accessed on 2018-08-16.