Phylum: Basidiomycota Family: Russulaceae
Lactarius lacunarum Romagn. ex Hora
Widespread but infrequently recorded. Found under broadleaved trees, especially Alnus, Populus and Betula
References:
Breitenbach & Kranzlin (2005) Fungi of Switzerland, Volume 6, Russulaceae
Heilmann-Clausen, Verbeken & Vesterholt (2000) The Genus Lactarius