Description: Where trees line dusty waysides, look for this species forming large, spreading grey rosettes on well-lit bark with Flavoparmelia soredians, Physconia distorta, Physconia grisea and Candelaria concolor (all described elsewhere). It has the general, leafy appearance of a grey Parmelia. It mostly resembles Punctelia subrudecta except for the black underside (inwards of the margin), the lobe tips which lift up into ridges around the edges, and the irregular white spots or pseudocyphellae (becoming coarsely sorediate) on the upper surface. The reddish discs can be up to 5mm diameter. Most of Ireland, probably under-recorded, rarer in the north.

Key Identification Features:

• Lower surface of lobes black away from the edge
• The white spotting of the lobes sometimes becoming coarse, developing into soredia.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Punctelia borreri at iNaturalist World Species Observations database.