Sium water parsnip
(For a dichotomous table for galls on Sium by Hans Roskam click here)
Dichotomous table for leafminers
1a mine < 1 cm, full depth, often in numbers together in a leaf axil; larvae, with distinct feet and chitinised head, later live free and cause extensive window feeding: Epermenia chaerophyllella
1b mine > 1 cm, not full depth; larva a maggot => 2
1c galls, etc => Tables for all parasites per species
Dichotomous table for leafminers
1a mine < 1 cm, full depth, often in numbers together in a leaf axil; larvae, with distinct feet and chitinised head, later live free and cause extensive window feeding: Epermenia chaerophyllella
1b mine > 1 cm, not full depth; larva a maggot => 2
1c galls, etc => Tables for all parasites per species
2a primary blotch mine: Euleia heraclei
2b corridor mine: Phytomyza sii