• Peterjamesia circumscripta (Taylor) D. Hawksw. (2006)
Peterjamesia circumscripta
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This lichen is only encountered on sheltered acid rocks by the sea where it inhabits dry shady underhangs. It is mosaic-forming with a thin, white thallus which scratches orange-yellow and there are numerous minute grey discs (about the same size as those of Enterographa crassa) that show up better when wetted with the tip of a finger. The thallus is C- which is sufficient to separate it from its companion species, many of which are C + red. Maritime. Throughout Ireland, but less common in the east.

Key characteristics

  • Mosaic-forming, maritime, dry underhang species with a white, scurfy thallus and tiny inconspicuous discs
  • Thallus scratches orange-yellow with a fingernail and is C (fresh bleach) negative.

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Peterjamesia circumscripta (Taylor) D. Hawksw. (2006). [In] LichenIreland. Accessed on 2018-07-23.