The larva of the fly Phytomyza crassiseta mines the leaves of Germander Speedwell, Wood Speedwell and Heath Speedwell, producing a narrow mine which follows the leaf margin, then turns and forms a secondary blotch.
In areas where the larval foodplants occur.
The mines can be seen in June-July and September-November.
Widespread and fairly frequent in Britain.
Rare or under recorded in Leicestershire and Rutland.
Leicestershire & Rutland Map
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