• Lecidea confluentula Mull. Arg.
Lecidea confluentula
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A very rare, granite-loving species celebrating the Irish lady lichenologist Matilda Knowles when first described in 1956 as L. matildae. This lichen is unusual in that it has a thallus without a cortex (major visible top layer). Instead, a black prothallus dominates. The flat black, sometimes pore-like discs (<0.4mm diam.) have brown outer rims C+ faintly reddish. The epithecium is brown throughout with no coloured granules. In Ireland, it was collected from the Lagnaquilla Mountains, County Wicklow. Not in Britain.

Key characteristics

  • Thallus without a cortex; prothallus black bearing small, flat black discs with C+ faintly reddish outer rim (exciple); epithecium brown throughout
  • On granite, tightly bound to the crevices between the crystals; test exciple in the field with C.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Lecidea confluentula Mull. Arg.. [In] LichenIreland. Accessed on 2018-08-14.