Silver-studded Blue Butterfly (Plebejus argus)
The Silver-studded Blue gets its name from the light blue reflective scales found on the underside of most adults and which are quite visible when light reflects off them. As with many other species of blue, the males are blue while the female is a less-conspicuous brown, although this butterfly is highly variable and several named subspecies have females with a certain amount of blue on their wings.
This delightful butterfly is found in close-knit colonies, with individuals rarely flying any distance. Most colonies contain less than a thousand adults. However, a few colonies are huge, with the number of adults measured in tens of thousands, providing an amazing spectacle. Most colonies of this species are found in southern England, although there are several other notable colonies in the east of England and Wales. With the exception of a single site at Prees Heath in Shropshire, this butterfly is absent from central and northern England, Scotland, Ireland and the Isle of Man.