Diptera: Anthomyiidae - root-maggot fly Chirosia betuleti Photographs on Dryopteris Hosts: Athyrium filix-femina and Dryopteris cristata, dilatata, filix-mas Eggs are laid at tip of fronds, larvae tunnel into main veins causing twisting and distortion. Can be found from early summer onwards

Chirosia betuleti
Badbury Rings, Dorset. August 2017