Emperor Moth

  • Emperor Moth (female)
    Emperor Moth (female)

Scientific name: Saturnia pavonia

Males fly rapidly in the day and are often mistaken for a Small Tortoiseshell butterfly.

The female flies at night when it occasionally comes to light, usually early in the night. The female is larger than the male with slightly different markings, has a paler colour and does not have feathered antennae (unlike the male). Northern or upland examples are more intensely coloured, with the female bluish-grey.

Size and Family

  • Family group: Emperors (Saturniids)
  • Large Sized
  • Wing Span Range (male to female) - 55-80mm

Conservation status

  • Common

Caterpillar Description

Overwinters as a pupa within a light brown, papery pear-shaped cocoon, with a closed circle of upward pointing spines around the opening. It is attached to a plant stem near the ground. Eggs are laid in April to May in batches attached to the foodplant. Larva late May to August

Particular Caterpillar Food Plants

Heathers, Meadowsweet (Filipendula ulmaria), Alder Blackthorn (Frangula alnus), Bramble (Rubus fruiticosus), Hawthorn (Crataegus monogyna) Blackthorn (Prunus spinosa), sallows(Salix spp.) and birches (Betula spp.).


  • Countries – England, Wales, Scotland, Ireland
  • Widely distributed in most parts of mainland Britain, the Channel islands, Isle of Man, Orkney, Hebrides and Ireland.
  • Distribution Trend Since 1970’s = Britain: Suspected stable


Heathland, moorland bogs, fens, hedgerows, field margins, woodland ridges, mature sand dunes and other scrubby places.