Phylum: Basidiomycota Family: Hydnaceae
Sistotrema sp. Fr.
This doesn't key out to any of the known species because of the size and shape of the spores. It is catalogued here for reference
Bernicchia & Gorjon (2010) Fungi Europaei 12: Corticiaceae s.l.
Hugill & Lucas (2019) The Resupinates of Hampshire