A very common corticioid fungus, found on the underside of dead wood on a wide range of deciduous trees

References: 
Hugill & Lucas (2019) The Resupinates of Hampshire
Læssøe & Petersen (2019) Fungi of Temperate Europe, Volume 2
Bernicchia & Gorjon (2010) Fungi Europaei 12: Corticiaceae s.l.