We found this inside a Birch leaf, purely by chance. It appears to be some kind of larvae but we are hoping someone might be able to let us know what it is, thanks!
No interactions present.
I was just passing in my quest to visit all Birch Leaf Miners before posting my own - something we should all do!
I found this http://www.leafmines.co.uk/html/Lepidoptera/E.sparrmannella.htm
and this http://www.dorsetnature.co.uk/pages-moth/bf-9.html
which have the rather convincing frassthreads.
Lat/Lng: 50.15413, -5.07146
OS grid ref: SW806327