Scientific name: Acronicta psi
Mid-May to August. Common throughout England, Wales and Ireland, scarcer in Scotland. Being virtually identical to the Dark Dagger, it is almost impossible to distinguish between the species by the external markings alone. For certainty it is necessary to inspect the genitalia.
The daggers get their English name from the black dagger-like marking found on their forewings.
The bright red and yellow larvae have a tall black hump on the back, close to the head and can be seen between July and October or November. They overwinter as pupae under loose bark, in a crevice or in rotten wood.
Size and Family
- Family – Daggers (Noctuidae)
- Medium Sized
- Wingspan Range – 34-40mm
- UK BAP: Priority species (Research only)
Caterpillar Food Plants
A range of broadleaved trees and shrubs including Blackthorn (Prunus spinosa), hawthorns, Apple (Malus domestica) birches, Sweet Chestnut (Castanae sativa), limes, elms and Rowan (Sorbus aucuparia).
Found in most habitats but particularly woodland, hedgerows and gardens. Also found in scrub areas of heathland, calcareous grassland and fens.
- Countries – England, Wales, Scotland and Ireland
- Common and well distributed throughout England, Wales, the Isle of Man and Ireland as well as the Channel Islands. Widely distributed in the lowlands of mainland Scotland and in the Hebrides.