Phalaris arundinacea
The larvae feed on a number of different species of grass including "Agrostis", "Avenula pratensis", "Avenula pubescens", "Brachypodium pinnatum", "Brachypodium sylvaticum", "Bromus erectus", "Bromus sterilis", "Calamagrostis epigejos", "Dactylis glomerata", "Deschampsia cespitosa", "Elymus hispidus", "Elymus repens", "Festuca ovina", "Festuca rubra", "Festuca trachyphylla", "Festuca valesiaca", "Holcus lanatus", "Holcus mollis", "Koeleria glauca", "Koeleria grandis", "Koeleria macrantha", "Leymus arenarius", "Phalaris arundinacea", "Phleum" and "Poa pratensis". They mine the leaves of their host plant. The mine starts as a narrow corridor in which the larva hibernates. In March, it vacates the mine and moves to a new leaf where it creates a transparent, full depth mine that descends from the leaf tip, and occupies the entire width of the blade. Most frass is deposited in the oldest upper part of the mine. The larva may again vacate the mine and restart elsewhere. Larvae can be found from late summer to early May. They are grey green with a pale brown head. Pupation takes place outside of the mine.