Pegomya solennis

Pegomya solennis is a small blackish fly whose larvae mine the leaves of various members of the Dock family causing large blotch mines.

The adults must be bred to identify the species as several Pegomya species mine Dock.(reference British Leafminers website).http://www.leafmines.co.uk/html/Diptera/P.solennis.htm

Around dock plants.

The mines can be seen when dock is in leaf.

The emerging larvae initially work shoulder to shoulder in making a broad corridor. Later they split up, making a large blotch that often is enlarged even more by fusion with other mines. The mine is practically full depth. Frass blackish-green, often deliquescent. The larvae can leave a mine and restart elsewhere. Pupation outside the mine.

Fairly frequent and widespread in England and Wales.

Fairly frequent in Leicestershire and Rutland.