Agrostemma corn cockle
Dichotomous table for leafminers
1a larva not only mines the leaf disc but also the petiole and stem, that become partly hollowed out and translucent: Delia echinata
1b mine exclusively in the leaf => 2
1c galls, etc => Tables for all parasites per species
2a fleck mine; larva in a tubular silken case: Coleophora corsicella
2b no fleck mine => 3
3a mine small (< 1 cm); larva with thoracic feet and a sclerotised head => 4
3b mine larger; larva a maggot => 5
4a pinacula colourless (only the base of the setae black): Cnephasia incertana
4b pinacula black: Cnephasia asseclana
5a mine whitish with few (fine, black) grains of frass; larva: rear spiraculum blunt with 3 clear, hooklike papillae: Amauromyza flavifrons
5b mine greenish; frass powdery in green clouds, mainly along the margin of the mine and in the end of short side branches; rear spiraculum acute, papillae almost invisible: Scaptomyza graminum