Description: This is the commonest member of the genus Arthopyrenia, which contains many ‘bark-pimple’ species with spherical discs. The minute black discs are concentrated into little constellations of black dots. It occurs especially on twigs, narrow branches and the smooth bark of trees. It is common on suitable habitats throughout Ireland.

Key Identification Features:

• Pimple-like discs, black, in constellations
• On twigs and small branches of young trees; it can only be confidently distinguished from other members of the genus by microscopic examination of the spores.

Original text submitted by Simon Davey

Distribution Map from NBN: Naetrocymbe punctiformis at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Naetrocymbe punctiformis at iNaturalist World Species Observations database.