Last modified: Nov. 13, 2019, 10:47 p.m.
A not so common species in Belgium but found more often after 2004.
A seed of the food plant is used as case.
See also bladmineerders.be.
The larva spends almost its entire life in a seed-capsule, feeding on the ripening seeds. Only fully grown, it makes a silken case within the now empty and dry capsule. Very often it leaves the host plant and walks up a tree where it gnaws a cavity in the bark, leaving the case behind, and enters the winter diapause. The larvae are full fed and leave their capsule in mid June. The adults are most of the time deep in a flower to suck the nectar. They are day active but also come to light.
The adults fly in one generation a year, from the end of April till the end of May.
In Belgium this species is monophagous on Stellaria holostea.