Black lirellae on sycamore

Black lirellae on sycamore

Observation - Black lirellae on sycamore - UK and Ireland. Description: Black lirellae on side of sycamore trunk. No definite thallus. Possibly Opegrapha atra.

Black lirellae on side of sycamore trunk. No definite thallus. Possibly Opegrapha atra.