Dasineura fraxini is a small gall midge that causes a gall to form on the underside of the main vein of Ash leaves. The area becomes swollen to form one or more pouches with a slit-like opening on the upperside, 5 to 30 mm long.

Dasineura acrophila causes the leaf to fold upwards into a 'pod'. 

Gall  Adult

Found on Ash. The gall is seen more often than the insect itself.

Gall is found from late May to October.

One small orange larva may be found in each pouch.  Pouches may coalesce.

Fairly common and widespread in England at least.

Fairly common in Leicestershire and Rutland.