Argent & sable

Rheumaptera hastata

  • Where it lives:

  • Non native species

About

The argent & sable is a day-flying moth with distinctive black-and-white wings. It is found on moorland, bogs and in open woodland, particularly with coppiced birch trees. It was once found throughout the UK, but the species has become much less common in recent decades.

Adult moths take flight on warm and sunny days from May to July. Males dash around in search of females, following the pheromones they release. Females lay eggs on the leaves of young birch trees, or sometimes on bog-myrtle or occasionally sallows. The caterpillars spin the leaves together and live within them, feeding throughout summer. In the autumn, they pupate in leaf litter on the ground. They spend the winter as a pupa, emerging as an adult the following spring.

How to identify

A distinctive moth, with mottled black markings on its white wings. It has a broken black band running across the centre of the forewing. The similar small argent & sable is smaller and usually has a continuous black line across the centre of the wing.

Did you know?

There are two subspecies of argent & sable in the UK. The moths found in the northwest of Scotland (Rheumaptera hastata nigrescens) are smaller and have more intricate markings than those found elsewhere (Rheumaptera hastata hastata).