Last modified: Jan. 21, 2021, 11:44 a.m.
A common species in the northern part of Belgium, less common in the south.
The adults fly from the end of May till the end of July. They rest on thistle-heads in the evening and come to light.
At first, the larva feeds on the seeds of Cirsium vulgare, C. eriophorum, Onopordum or Arctium lappa, preferably large plants. Later on it enters the stem and feeds on the pith, hibernating when nearly full-grown, often several caterpillars in one stem. Hibernation in the stem, near its circular exit-hole.