Circumscription: Medium sized Inkcap with remarkably white-grey pileus and recurving, filamentose-floccose velum remnants which lie loosely on the pileus, growing in a cavity of a trunk of a cut-down Fagus (Beech). A very rare species in the Netherlands, listed as Critically Endangered on the Red List of 2008 (Arnolds & Veerkamp, 2008).