Caliciaceae Acolium sessile (Cyphelium sessile) # Lichenicolous fungus on Pertusaria coccodes Chemical results: Only those of the host Left and immediately below identified by Bryan Edwards, Vince Giavarini Usually found on Pertusaria coccodes on old, well-lit oaks. Occasionally recorded from Pertusaria amara and P. albescens Apothecia sessile, not pruinose, the discs black. Spores brown, 1-septate, constricted at septum, (10-)12-15 x 6-9 µm. Micro photo below. Similar: Cyphelium inquinans. K+ yellow > red and larger spores

Microscope photograph

Acolium sessile (Cyphelium sessile)
On Pertusaria coccodes. Holton Lee, Dorset. March and April 2013