The larvae of the midge Dasineura hyperici cause galls on various Hypericum species (e.g. St John’s-worts). The topmost leaves form a loose ball; the basal part of the leaves is swollen and discoloured, but the upper part is not affected as much. There may be several larvae to a single gall, they are whitish at first, becoming orange or red later. 

Dasineura serotina on St John's-wort

Gall Adult  

Please provide photographs of the gall and of the larva(e). It may not be possible to confirm records unless the larva is photographed. Please also state the host species.

Where the host Hypericum species occur.

The gall may be found when the host Hypericum species are in leaf.

Pupation in the gall, two or three generations per year.

True status in Britain is difficult to determine due to lack of records.

Rarely recorded in Leicestershire and Rutland.