Best time to see: late Apr to mid Sep

Key facts

White butterfly with spectacular veined underwings

Habitat: damp uncultivated places, such as boggy meadows and along the edges of woods

Widely distributed across Britain

Recognition

Looks like a Small White when flying, but at rest shows the grey-green stripes along the veins of the underwings

Weak fluttering flight but very mobile, searching large areas for mates and breeding sites

Congregate in large numbers around breeding sites, especially in August; wingspan 5 cm

Lifecycle

Pale eggs laid on crucifers such as Lady's Smock or Garlic Mustard, in May/June and again in August

Well camouflaged dark green caterpillars feed on stems and leaves of foodplants

Later broods over-winter as a chrysalis, hidden in dense vegetation, emerging in early spring