Wall Brown Lasiommata megera

There are 16 Lasiommata species distributed variously across Europe and temperate Asia. Some workers classify Lasiommata as a subgenus of Pararge, which comprises of a further 3 species.
The Wall Brown is found across most of Europe with the exception of northern Britain and northern Scandinavia. It also occurs over much of north Africa, and in temperate regions of western and central Asia.
Habitats
In England and Wales the Wall Brown was formerly more widespread, and occurred in a wide range of habitats. In the latter part of the 20th century it became evident that most of the inland colonies were dying out, and the species was contracting it's range westward, and towards coastal regions.
At the current time ( 2008 ) the species is restricted largely to sites within about 10-15 miles of the coastline, and is most frequently encountered at coastal habitats : cliff-tops, undercliffs, south-facing grassy slopes, shingle banks, sea walls and sand dunes.
There is some evidence that the butterfly is beginning to regain lost ground, recolonising inland sites e.g. in Dorset, Wiltshire, and in the north of England. The most northerly colonies occur around the coast of southern Scotland.
The reasons for the collapse of inland colonies, and the recent slight recovery, are probably related to climatic changes. The butterfly seems to thrive best when cold and harsh winters are followed by warm dry summers, and to collapse when winters are mild and wet. It clearly needs conditions to be warm and sunny during the flight periods, and even if there is enough warmth for eggs to be laid in reasonable numbers a few days of rain can easily cause them to be washed away. Over 8 months of the lifecycle are spent in the caterpillar stage, and if conditions are mild and wet between September and April, as they have been in recent years, the larvae are more prone to viral attack; and exposed for an extended period to predation and parasitism.