Oak Marble Gall Wasp

A follow-up to my previous post. The Oak Marble Gall that I picked up in the Coryton interchange last week revealed its secret this morning. I found a neat little hole in the gall and a little wasp in the pot. I assume this must be an Oak Marble Gall Wasp - Andricus kollari. (the grid is 2mm). Always wanted to see one of these gall wasps.