Northern Brown Argus - Aricia artaxerxes artaxerxes

There is a magical little corner in a valley close to where my father lives in the Scottish Borders which has remained untouched for years. Amongst the heather and grasses there is a lot of rock rose, which is the foodplant for the caterpillars of the Northern Brown Argus butterfly, Aricia artaxerxes. The valley runs for about a kilometre up into the moors, but the best area is a sheltered slope next to an old oak wood. Below the slope is a flatter damp area next to the burn (stream). The butterflies tend to fly on the south-facing slope during the day and then roost amongst the taller grasses and sedges in the bottom of the valley in the evening.

The yellow flowers of the Rock Rose, Helianthemum nummularium, stand out in the sunlight, but unfortunately when I visited this area last year it was quite overcast.

Despite the weather there were still quite a few butterflies around.

The reason I visit, each June or July is to see the Northern Brown Argus. These are a small butterflies with a wingspan of about 25 to 30mm. They occur only in the north of England and Scotland and the sub-species artaxerxes, which has the distinctive white spots on the forewings, is only found in Scotland. This one is a male.

The underside of the wings is similar to many blue butterflies, but the Scottish sub-species often lacks the dark spots inside the light markings.

This one is a female and just after I took this picture she flew off and laid an egg!

Although the eggs are small they are quite easy to find on the dark Rock Rose leaves.

This is really a little beyond the macro capabilities of my camera and this is the best I could do I am afraid. This egg is only about half a mislimetre across, though!

Another butterfly that is very common in this area is the Ringlet, Aphantopus hyperantus. 

And there are plenty of Common Blues, Polyommatus icarus.

There were also a lot of Meadow Browns, Maniola jurtina;

Small Whites, Pieris rapae;

Green-veined Whites, Pieris napi;

Dark Green Fritillaries, Argynnis aglaja;

And my first ever Small Pearl Bordered Fritillary, Boloria selene.

This area used to be quite heavily grazed by sheep, but recently some trees have been planted in the bottom of the valley and it is no longer grazed. I hope that the bracken doesn't take over and smother the Rock Rose. It would be a real tragedy to lose this magical little corner.