• Lasallia pustulata (L.) Mérat
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Lasallia pustulata
© Mike Simms
Lasallia pustulata
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(Map updated: 11 August 2009)

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Also called ‘rock tripe’ this is a very local species of nutrient-enriched, acid rock outcrops where it can form tremendous colonies. The circular, beige to dark brown thallus is anchored at its centre and is covered in large, pustule-like swellings, resembling a piece of oven-cooked Naan bread. In well-grown specimens the frayed edges become covered in near-black clusters of coralloid isidia. The medulla if tested is C+ red. Western and south-western Ireland. Extreme southern Ireland, thinly scattered elsewhere.

Key characteristics

  • Unmistakable, pale brown, circular thalli bubbled with pustules and edged with black clusters of coral-like isidia
  • On nutrient-rich acid rocks (for example, granites).

Original text submitted by Vince J. Giavarini

 Simms, M. J., (2016). Lasallia pustulata (L.) Mérat. [In] LichenIreland. Accessed on 2018-08-17.