The larva of the midge Dasineura serotina produces galls on Hypericum species. The gall is formed out of the terminal bud of a stem. The hyaline white larva is surprisingly small in relation to its gall.

Dasineura hyperici on St John's-wort

Gall Adult

Please provide photographs of the larvae and gall.

Where the host Hypericum species occur.

Galls may be encountered when the host Hypericum species are in leaf.

Larvae white, 2 to15 per gall. Hibernation as larva in the soil.

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

Status in Leicestershire and Rutland not known.