• Cetraria islandica (L.) Ach.
Cetraria islandica
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This is the iconic ‘Iceland Moss’. It has a loosely attached, shrubby thallus between two and six centimetres tall, a pale, dark red to brown colour with its surface ridged and pitted. The lobes are inrolled often with marginal projection tipped with pycnidia (pimply spots). Medulla Pd+ orange-red (this distinguishes it chemically from C. ericetorum). In hilly, lichen-rich heath usually on mountain slopes. Rare, northern and western Ireland. (Iceland Moss is an important reindeer and caribou staple; it may be eaten by humans, but not without lengthy preparation: not recommended)

Key characteristics

  • Dark reddish or brown, shrubby thallus, the branches inrolled with marginal ‘spikes’
  • Medulla Pd+ red, high upland heaths.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Cetraria islandica (L.) Ach.. [In] LichenIreland. Accessed on 2018-08-16.