The Common Blue is one species of UK butterfly which shows marked differences in wing colouration between the sexes and there is also a difference in the appearance of the females between northern and southern Britain. The female upperwings are brown and blue with orange margins and individuals from Scotland typically have a higher proportion of blue colouration than those found in England and Wales and completely brown individuals are rare in Scotland. Below is a female Common Blue from the Rannoch area which is more blue than brown
Arguably, the undersides of Common Blue are more beautiful than the upperwings as shown below:
The Northern Eggar which is found on moorland in northern England, Wales and Scotland is a northern sub-species of the Oak Eggar which is found in southern Britain. As well as some difference in the markings, a notable difference between the sub-species is the length of the life-cycle with Oak Eggars having a one-year life cycle while Northern Eggars have a two year life cycle with it overwintering as a small larva in the first winter and as a pupa in the second winter. The flight period is late May to July in Scotland when it can be seen flying fast on moorland - it is a large dark brown moth! But at the same time as seeing adults in flight, the two year life cycle means that you may encounter fully grown caterpillars at the same time as seeing adults in flight. While the bright green with yellow spots fully grown larvae of the Emperor moth certainly are the king of caterpillars in the UK, the caterpillars of the Northern Eggar come a close second. They are large - up to 8 cm - and brown with a stripy appearance and can be found feeding on heather by day. The photo below was taken in the Rannoch area.
While the Meadow Brown is certainly not one of the UK’s most beautiful butterflies, its underwings are perhaps more attractive than its upperwings with a two-tone colouring.
The Small Copper is always a delight to come across with both its upperwings and underwings being a colurful copper colour.
Even with big chunks of wing missing, possibly from a bird attempting to eat it, this Small Copper still manages to look bright and colourful
The Welsh Clearwing is a red data book species and its UK stronghold is in Wales where it was first found at Llangollen in 1854. It was first recorded in Scotland at Rannoch in 1867 and other sites where it occurs locally in Scotland are the Trossachs, Perth, Sutherland and Glens Affric and Moriston.
It has a two year life-cycle with the larvae feeding on the inner bark of old birch trees. The fully-grown larvae shortly before spinning a cocoon and pupating, bore a tunnel to the bark surface just leaving a thin barrier of bark. This allows the adult moth to emerge from its pupa and escape to the outside world in the following late June and July. This sequence of events leaves a characteristic exit hole 5 mm wide and these are visible for many years. Just after emergence, the holes are perfectly round and the edges show fresh wood and sometimes, the remains of the pupae (pupal exuvium) can be seen protruding from the exit hole. More info on Welsh Clearwing will be posted on the blog later in the year but in the meantime, here are a few photos.
Written by Andrew Masterman