- Family: Brushfooted Butterflies – Nymphalidae
- Subfamily: Browns – Satyrinae
- Wing span: Medium-sized, 36–55 mm (1.4–2.15 in.). Females larger than males.
- Wing upper side: Basal part of hind wings greyish brown, outer part yellowish beige. Male forewing with same colouring, female forewing completely yellowish beige. Black eyespot at apex of forewing, possibly with white centre. Females with second spot in back corner of forewing.
- Wing underside: Forewing mainly same as upper side but with grey margin and possibly three eyespots. Hind wing a colourful combination of greyish white, black and brown. Centre with varyingly clear brown lateral band.
- Habitat: Bogs and moors.
- Flying time: Late June–mid-July.
- Overwintering form: Caterpillar (overwinters two seasons).
- Larval foodplant: Different grasses (Poaceae) and sedges (Carex).
- Endangerment: Vulnerable.
The Brushfooted Butterflies (Nymphalidae) are the largest butterfly family in the world with over 6,000 species. In Finland the family is represented by around 60 species, which are nowadays usually divided into five subfamilies. The largest of these is the Browns (Satyrinae), with around 20 species. The Browns can be further divided into a number of groups including e.g. browns, heaths, ringlets and graylings.
Norse graylings always rest with their wings pressed against each other, making the upper side difficult to study without first catching it. In the species’ habitat in northern Finland it can only be confused with the jutta Arctic and the Arctic grayling, which also have yellowish beige and greyish brown forewings. The Arctic grayling lacks the eyespots that are typical of the Norse grayling, however. Further south the larger jutta Arctic also has an eyespot on the apex of the underside of its rear wing.
Like a number of other species that can be found in Lapland, (Norse) grayling caterpillars need two winters before entering a cocoon to emerge as butterflies.