Last modified: Feb. 11, 2020, 7:15 p.m.
A very rare and local species in Belgium, mainly found in marshy areas.
The larva lives in the stems and roots of the hostplant. Infested stems are recognizable by the brown frass in the center of the stem. The larva overwinters in the rootstock. In spring it pupates in the dead stem in a reddish brown silken cocoon, just a little below the prepared exit hole. The pupa protrudes the exit hole before emerging.
The adults fly from late May till July. They are active on warm sunny afternoons and later come to light.