Hebeloma radicosum -Rooting Poison-pie is an uncommon find. These two were under Oak in Dynefwr Park ---- unfortunately I did not recognise what I had so broke the stipe instead of digging out the 'root'! Hebeloma crustuliniforme is called 'poisonpie' hence the name used for this species.
The robust stipe is deeply rooting and arises from the 'latrine' of moles/mice or voles deep in the ground. I had never thought about mice etc having ladies/gents toilet cubicles. This is one of the 'ammonia' fungi ---- some think it may also be associated with decaying remains of small mammals.
The cap is quite slimy with small flat scales and it has a smell of marzipan (which even I detected). There is a prominent ring on the stipe.
As it must grow from fairly deep ---- how do the spores reach the desired location to develop? Any ideas --- are spores or fruiting-bodies eaten by small mammals and spores excreted in their latrines?