Wingspan c.15-24 mm.
Considered by some authors to be an ecotype of A. hartmanniana, this species is however still listed by most as a separate species. It is larger than hartmanniana, generally darker in colour, and the raised whitish spots do not coalesce to form striations as often as that species.
Frequenting damper habitats such as marshes and fens, it is locally distributed throughout much of the British Isles, and can be common in some places. Adults emerge in June and July and fly around dusk.
The larvae feed in the roots of devil's-bit scabious (Succisa pratensis).