Description: This small, bark lichen has long been considered a classic indicator of good quality woodland. The thallus is often only a thin, grey stain on mature, shaded, rough-barked trees such as oak (though actually, it appears most partial to areas of the trunk where the bark has, for various reasons, thinned or been lost, and has instead become rather spongy). The tiny discs (c. 0.5mm diam.) lie just embedded in the bark like miniature, red wine gums — paler when young, darker when old — with a neat raised margin. They have up to 48 spores per ascus (microscope to see). Uncommon; south and south-west Ireland.

Key Identification Features:

• Thin, whitish-grey stain on sparingly mossy bark with tiny, partly sunken, red, wine-gum-shaped discs
• Shaded trunks of old deciduous trees, especially oak, provide ideal habitats for this species. The red discs separate it from all but Gyalecta derivata which has eight-spored acsi (spore bags) and occurs on more nutrient-rich bark.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Pachyphiale carneola at iNaturalist World Species Observations database.