Resident. Occurs sparingly, but sometimes fairly common at light along all parts of the coast. Widespread, but very local and irregular in high numbers. In Sussex costalis is often double-brooded fying between early June and late August, and again from mid September to early October. Larvae feed on stacks of clover. (Pratt, 2011).
Burgess Hill, 01 vii 2020 Photo: Sarah Bonnot-Tijhaar