Dasineura affinis

The larvae of the midge Dasineura affinis cause purple galls on the leaves of Viola riviniana, V reichenbachiana and possibly V canina.  The galls take the form of rolls on one or both sides of the leaf causing them to look like a pouch. The galls are sometimes hairy, with several adjacent leaves affected. On young leaves the rolls affect the whole leaf, but on older leaves only part of the blade is affected. The larvae are white when young later turning orange-yellow.

Very similar galls occur on Viola odorata and Viola hirta.

Gall  Adult

Ensure you have identified the host species of Viola correctly; provide photos of the host plant.  See our Wildflower species galleries for guidance on identifying Violets. https://www.naturespot.org.uk/family/violaceae

Where the host violet species occur.

When the host violet species are in leaf.

It appears to be widespread, but very poorly recorded in Britain.

Status in Leicestershire and Rutland not known.