Last modified: May 17, 2021, 4:18 p.m.
A rare and local species throughout Belgium.
Wingspan 10–14 mm. Forewing unicolourous reddish-brown with coppery hue. Head ochreous yellow with some mixed black hairs in the male, ochreous yellow in the female. Antennae very thin and 2.5 times the length of the forewing in the male, thickened in the basal half and 1.5 times the length of the forewing in the female.
Yellowish white; head and prothoracic plate dark brown, almost black; mesothoracic plate brown and metathoracic plate light brown.
Oval case with more or less parallel sides, sometimes tapering towards the end, 7–9 mm long, constructed from dry plant pieces which are cut into more or less crescent-like particles and glued together with sand or detritus. The first case is constructed in the flower of the food plant using the excrements of the larva.
Oviposition in the seed capsules of different species of Hypericum. The larva lives on the flowers and seeds of the food plant where it consumes both the fresh, greenish new leaves or the dry, dead leaves of the plant on which the eggs were laid. Hibernation as a larva, but in different stages of development. Perhaps some caterpillars need two years for their development. Some hibernating larvae crawl to 10 cm deep in the soil while others remain amongst the detritus on the soil. They still feed on detritus in early springtime. Pupation in early spring.
The adults are active in the sunshine. They have been observed feeding mainly on plants with white flowers like Leucanthemum vulgare and Achillea millefolium.
The adults fly in one generation a year from June to early August.
Different kinds of habitats as long as there are extended stands of Hypericum, preferably at forest edges or on open places inside forests. Both rather dry and warm habitats as cool and wet biotopes are accepted.