Diptera: Sciaroidea Cecidomyiidae - Macrolabis pavida Iniquiline larvae in Dasineura acrophila gall on Fraxinus The white larvae lack the blue-green colouration of the gut content that is visible in the Dasineura acrophila larvae in the photographs below

Macrolabis pavida
In Dasineura acrophila gall collected Upton Country Park, Dorset. May 2018