The pale caps are 2 to 7 mm across. See link below for full description.

Mycena pseudocorticola and M meliigena are very similar and found in the same habitat.

microscope

This is a difficult species, and we recommend that it is verified by an expert from a specimen before submission to Naturespot.  Microscopic examination will be needed.  Also photograph from top down, in side view and underneath to show gills; note habitat and substrate.

On moss-covered trunks of deciduous trees, possibly mostly in rich, calcareous sites.

Autumn and early winter.

A rare species which was only discovered in Britain in Cornwall in 2020.

Rare in Leicestershire and Rutland.

https://www.mycena.no/supina.htm