The larvae produce a long mine which ends in whitish blotch. A case is cut from the end of the blotch leaving an oval hole approximately 4mm long. The case falls to the ground where the larva pupates.
Recorded in 5 (1.9%) of the 270 2km squares of Huntingdonshire.
Last recorded in July 2018
Recorded date range (Adult): 09 May to 03 June
Recorded date range (Larva/Leafmine): 02 July to 11 November