Last modified: Feb. 18, 2020, 9:46 a.m.
A fairly common species in Belgium.
Usually the egg is deposited on the upperside of the leaf.
The larva makes a leafmine usually starting close to a rib on the upperside of a leaf. It's long sinuous gallery completly filled with dark green frass. Due to the green frass the mines are difficult to find. When the mines are vacated the green frass turns brown and rendering the mine more conspicuous.
See also bladmineerders.be
Bright reddish brown.
The adults fly in two generations a year; during May and June and again in September till early October.