Brown y Wal
Fairly common butterfly
in Lleyn. Any unimproved
of land with wild flowers and tall grasses may be suitable provided there
are also areas of bare soil or rock. Indeed, it is the habit of basking on
rocks that gave rise to the vernacular name, as the rocks chosen often form
part of a stone wall.
The butterfly is common in sand dunes, where it basks
on the bare sand, and in rough areas with boulders or scree. The summits
of rocky hills are often especially favoured.
A double-brooded species which can be seen flying in May and early June and then
again from the end of July, throughout August and into early September.
are laid singly on various species of grass such as Cock’s-foot (Dactylis
glomerata), Yorkshire Fog (Holcus lanatus) and Wavy Hair-grass (Deschampsia flexuosa).
The larvae hide by day, emerging at night to feed on the grass leaves. The species
overwinters in the larval stage.