[mollisia]

Hi solus,

I can understand your frustration to a certain degree, but on the other hand the group of fungi you posted here - the Corticiaceae or "crusts" - are always a guarantee for frustration, because you nearly never can tell the species with certainty macroscopically. In a few cases one can give a probable name, but in most cases, especially with the white, ochraceous, grey and blueish-violaceous ones, there is no way to tell a species name. Not even when they grow on ivy, because only few of them are host specific.
And even with the aid of micorscope it is often not possible to give a name bacause the specimen is either not ripe, or overmature, or from a group were not yet a useable monographic treatement is published (Athelia i.g. ....) and so on.

best regards,
Andreas