Univoltine, with an extended flight period. In central and southern Europe the females fly from April to the end of August , males from early July to mid August
Label data from a few Spanish specimens shows that females are active from (at least) April to August, and males are active in August (Ortiz-Sanchez & Pauly, 2017). Else (in prep.) reports that British females have been collected in late April, June, August and September, males in late August and September.
In Poland, the females emerge from hibernation in late April and fly until October, The males fly from late July to September (Pesenko, Banaszak et al., 2000).
Parasites None known.