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Swallowtail Butterfly

©Terry Whittaker/2020VISION

Swallowtail

The exotic and beautiful swallowtail is the UK's largest butterfly. A strong flier, residents can be spotted over wetlands in Norfolk during summer. Migrants occasionally appear in southern England.

Scientific name

Papilio machaon

When to see

May to July

Species information

Category

Statistics

Wingspan: 7.6-9.3cm
Protected in the UK under the Wildlife and Countryside Act, 1981.

Habitats

About

The UK's largest butterfly, the swallowtail is striking and exotic-looking. Adults fly between May and July when they can often be seen over reedbeds, or feeding on ragged-robin or flowering thistles. Swallowtails are restricted to reedbeds and marshlands in the Norfolk Broads; very rarely, migrants from the Continent appear on downland in southern England. The foodplant of the caterpillars of our native race is milk-parsley, whereas migrants may feed on wild carrot.

How to identify

The swallowtail is a large and unmistakeable butterfly. It has creamy-yellow wings with heavy black veins and blue margins. The hindwings have distinctively long 'tails' and a red spot.

Distribution

Native to the Norfolk Broads. Migrants may be spotted in southern England.

Did you know?

The UK population of the swallowtail is a unique subspecies, Papilio machaon britannicus, found only here.