LichenIreland
  • Collema flaccidum (Ach.) Ach.
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Collema flaccidum
© Mike Simms
Collema flaccidum
© Mike Simms
Collema flaccidum
© Mike Simms
Collema flaccidum
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(Map updated: 11 August 2009)
Collema flaccidum
© Mike Simms
Collema flaccidum
© Mike Simms
 

When dry, this ‘aquatic’ lichen is easily told by its thin, black, broad-lobed, ragged-edged thallus growing on acid rock by streams or along the margins of loughs. The thallus is covered in a mass of tiny outgrowths (isidia) like little skin tags, later becoming flattened and scale-like. It will also grow on seepage rocks away from watercourses and on damp, mossy boulders in woodland. Frequent in the north and west of Ireland.

Key characteristics

  • Thallus thin and almost papery with numerous isidia; on rocks and boulders by stream courses and on wet boulders in oceanic woodland
  • Less distinctive and leafy when wet; an amphibious zone species.

Original text submitted by Vince J. Giavarini

 
 Simms, M. J., (2016). Collema flaccidum (Ach.) Ach.. [In] LichenIreland.
http://www.habitas.org.uk/lichenireland/species.asp?item=18439 Accessed on 2018-09-23.