Mycena rosea Rosy Bonnet.
For a long time this was considered a variety of Mycena pura, Lilac Bonnet (as in Bon 1987, Mushrooms and Toadstools). Tony Ivens recently sent me a picture, correctly named, taken from 'his woods' which alerted me to the name change. This photo is of a find on the edge of Ffrwd Fen growing in leaf litter. The cap has a delicate rose-pink colour and the stem is white. With M pura the colour is a pale lilac or violet although this is extremely variable (even yellow) so several 'forms' have been described. The stipe with M pura is generally coloured although almost white with some forms.
John James sent me this photo of a Rosy Bonnet taken at the Botanic Garden a week ago with a pale pink cap and white stem.