Marbled White (Melanargia galathea)

A Marbled White nectaring
on knapweed

Marbled Whites are beautiful, strikingly marked, virtually unmistakable butterflies that exhibit bold black and white patterning.

Of medium size - their wingspan is around 5.5 centimetres - they are on the wing primarily in July and August.

However, whilst elsewhere in much of Hampshire, Marbled Whites are widely distributed, particularly on the chalk; only relatively small numbers are likely to be seen on the Crown Lands of the New Forest. But this has apparently not always been so, for in the late 19th century, when grazing and browsing pressure was less than through much of the 20th century and butterflies of many species were consequently more abundant, the Marbled White was referred to as 'a really common insect'.

In recent years, though, they have occurred primarily on private meadows within the New Forest National Park area from where a number of small colonies have become established in woodland inclosures, particularly where commoners' stock have been excluded.

Most appropriately known in the early 18th century as the Half-mourner, the Marbled White's favoured nectaring plants include knapweeds, scabious and thistles, whilst a range of grasses form the main caterpillar foodplants.

References:
Butterflies of the British Isles: J.A. Thomas
The Butterflies of Hampshire: Matthew Oates, John Taverner, David Green et al
The Millennium Atlas of Butterflies in Britain and Ireland: Jim Asher, Martin Warren, Richard Fox, Paul Harding, Gail Jeffcoate and Stephen Jeffcoate
Insects of the New Forest - Paul Brock
British Butterflies and Moths - W. Furneaux, FRGS
Butterflies of the British Isles - Richard South, FRES
British Butterflies - W.S. Coleman