• Arthonia punctiformis Ach.
Arthonia punctiformis
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(Map updated: 11 August 2009)

This is a small, relatively insignificant species, common on the twigs of oak and hawthorn. It often grows with Arthopyrenia punctiformis. Its black, freckly discs are virtually unmistakable. In Arthonia these discs are flattened, whereas in Arthopyrenia they are always convex and pimple-like. It is common on suitable habitats throughout Ireland.

Key characteristics

  • Tiny (0.25mm diam.) black, smooth, freckle-like discs, never convex in shape
  • Always on twigs and very narrow branches.

Original text submitted by Simon Davey

 Simms, M. J., (2016). Arthonia punctiformis Ach.. [In] LichenIreland. Accessed on 2019-10-14.