Common in gardens, woodland rides, and on calcareous grassland, sand-dunes and sea cliffs throughout much of southern Britain; widely distributed and fairly common in Hampshire and on the Isle of Wight. Wingspan 35-41 mm. The main confusion species is Treble-bar A. plagiata, but innermost fascia usually more sharply angled in A. efformata. Larva feeds on St John's-wort.
The abundance in each month is indicated as follows:
No records
Very occasional
Irregular
Uncommon
Off-peak, but not unusual
Off-peak, but not unusual
Main flight time