Peacock Butterfly
Inachis io (Linnaeus, 1758)

Family: Nymphalidae (Nymphalinae) - Nymphs

Order: Lepidoptera - Butterflies and Moths

Class: Insecta

Phylum: Arthropoda

Kingdom: Animalia

Red List status: Not listed

Wingspan

Male: 63-68 mm

Female: 67-75 mm

Peacock butterfly. Epping Forest, Essex, United Kingdom
RANGE

Widespread across temperate Eurasia and as far north as southern Scandinavia, and east to Japan. This species is expanding its European range northwards.

Range            Description            Habitat            Behaviour            Biology            References

Other common names: European peacock butterfly

 

DESCRIPTION

Adult: The adult peacock is unique in its appearance, characterised by a deep reddish-brown ground colour to the wings with a striking, yellow-rimmed bluish eye spot at the apex of each wing. The margin of each wing is a darker, dull brown. Two thick black bands as long as the eye spot extend down the forewing, with a yellow flush between them. A series of five whitish spots form a line parallel with the margin of the forewing that runs through the eyespot and extends halfway down the wing. The species exhibits little variation throughout its range, although occasional individuals lack eye spots altogether.

In contrast to its extravagant upperwings, the underside is grey-brown and patterned to resemble bark, with a series of irregular black bands of varying intensity running across it.

Larva: When approaching full size, peacock caterpillars become black, covered with irregular white tubercles that give the animal a speckled appearance. Six hairy 'spines' project from each body segments Younger larvae are greyish-green, and can be found in large aggregations on nettle leaves. Young larvae live within a silk web they spin on nettle leaves.

Similar species: When seen from above, the peacock butterfly is unmistakeable and can't be confused with any other species. Some species, such as the painted lady, have similarly cryptic underwings, but these usually have some blue markings which are absent in the peacock. In appearance and behaviour, early-stage larvae resemble those of the small tortoiseshell (Aglais urticae).

 

HABITAT

The peacock butterfly is cosmopolitan in its foraging habits and so can be encountered in most habitats. These butterflies are common visitors to gardens. When searching for breeding sites, peacocks particularly favour woodland edges, hedgerows and forest clearings with a combination of sunny aspect and shade.

Elevation: 0-2,500 m

Larval food plants: Stinging nettles (Urtica dioica) in most of the species' range. Pellitories (Parietaria officianalis) will be used where stinging nettles are not indigenous. Occasionally other nettle species and hops (Humulus) may be used.

 

BEHAVIOUR

Males are territorial, and lay claim to areas of open, sunny ground around woodland edges and hedgerows, which they will abandon only to pursue females. Peacocks may migrate during their flight season, but in smaller numbers than in truly migratory species.

Diet: Nectar from willow blossoms is preferred by adults emerging from hibernation. Buddleias are commonly used as nectar sources by adult butterflies.

Flight season: June/August to October, although animals may enter dormancy as early as July in unfavourable conditions. Dormant animals emerge from hibernation between February and May, being most common in late April. Butterflies have been emerging progressively earlier over the last 30 years.

 

BIOLOGY

Breeding biology: Peacocks are typically univoltine, but two broods a year have occasionally been reported in favourable conditions, although these broods are smaller than the first of the year. Dull green, spherical eggs are laid in clutches of up to 500, often in several layers, on the underside of nettle leaves.

 

REFERENCES

Asher, J., Warren, M., Fox, R., Harding, P., Jeffcoate, G. & Jeffcoate, S. (2001) The Millennium Atlas of Butterflies in Britain and Ireland Oxford University Press, Oxford.

Hoskins, A. and Eeles, P. (2008) Peacock, UK Butterflies

Tolnan, T. and Lewington, R. (2008) Collins Butterfly Guide HarperCollins, London: 384pp

Inachis io, Wikipedia