Identifying features
Wingspan 37–49 mm. Both pairs of wings are white on the upper side, with varying amounts of grey dusting along the wing veins. The front wing tip has a dark area; the male exhibits both with and without a black spot on the forewing, while the female has two spots. The underside of the hindwing is yellow or yellowish-white, with distinct grey dusting along the wing veins.
Similar species
It resembles small white, but can be easily distinguished from both this and cabbage butterfly on the grey ribbing on the underside of the hindwing, and also on the generally more clearly defined wing ribs.
Distribution
Common throughout the country. In the mountains of Southern Norway (Jotunheimen and Dovre) as well as in Northern Norway, a form with strongly darkened females is observed.
Biology
The larvae live on various plants in the aster family. It is green with small yellow rings around the breathing pores on the sides of the body and measures approximately 25 mm. Overwintering occurs as a pupa.