A rather rare species in Belgium, mainly observed in the south.

The young larva lives in the seeds of Cardamine pratensis, but probably also on other foodplants like Alliaria petiolata, Sisymbrium officinale, Barbarea vulgaris or Cakile. Later on it constructs a flat, elongated-oval, bivalved case from which it feeds on the lower leaves of the same plants. Pupation in the case. The pupa hibernates.

The adults fly in May and June. They fly in the sunshine.