Description: Wingspan 32-40 mm. Forewings are greyish white marked with darker and irregular antemedian and postmedian lines. The stigmata are similarly coloured and outlined with a darker line. There is also a small black mark at the mesial end of the orbicular stigmata. The subterminal line is darker and irregular. Hindwings white in male, light grey in female with darker veining; fringe white Mid-August to mid-September.

World Distribution: Throughout western Europe from Spain to Finland.

Irish Distribution: In Ireland this species has not recorded south of Dublin and Clare. It is widely distributed in the north and recorded from all counties, but more frequently encountered in the east.

Ecology: A species that is generally associated with upland grassland and heathland, but in recent times it has been found in gardens and other suburban habitats, suggesting that it not restricted to its typical habitats. Adults appear at light in small numbers and may also be found by day at rest on stone walls and rocks. The larvae feed from April until early June on a variety of herbaceous plants and shrubs. It overwinters as an egg.

Key Identification Features:

• Marbled appearance when at rest
• Black mark at the mesial end of the orbicular stigmata
• White hindwings

Distribution Map from NBN: Antitype chi at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Antitype chi at iNaturalist World Species Observations database.