White Letter Day

It was a beautiful sunny afternoon in Batch Valley. I had spent the morning sorting through my last few moth identifications from Friday (more to come soon), when Jo came inside asking to see a butterfly identification book. After a quick check she told me there was  Dark Green Fritillary Argynnis aglaja on the Scabious in the garden! I rushed outside, and indeed there was, though it escaped my camera.

A short while later Heather and John, who live three houses aways, walked past on their regular afternoon walk. They stopped to let me know that Heather had seen a White-letter Hairstreak Satyrium w-album in their garden, and had the pictures to prove it! I was left feeling very envious as they headed off on their walk, as this is butterfly I have never seen. I then walked round the corner of the house, and there was a White-letter Hairstreak on one of our Achileas! I managed to get a couple of quick pictures before it headed off. This is not a common butterfly, partly because it depend on Elms (Ulmus sp.), which are not as common as they once were. Fortunately there are Elms in some of the local hedgerows, where they are kept short and less susceptible to Dutch Elm Disease.

White-letter Hairstreak Satyrium w-album

It was in fact a wonderful day for butterflies, with twelve species in the garden. This included the first Gatekeeper Pyronia tithonus of the year, with several in and around the front hedge.

Gatekeeper Pyronia tithonus

Trying to relocate the White-letter Hairstreak, I noticed that our Scabious was covered with a selection of bees and flies. This included a large number of hoverflies, including the bumblebee mimic Volucella bombylans. This was the white-tailed variety plumata.

Volucella bombylans

There were also a couple of very interesting Diptera species, ones that did not look much like typical flies. The first of these was Sicus ferrugineus, one of the thick-headed flies Canopidae. This is a bumblebee parasitoid, though the adults are nectar feeders (like this one). They have a characteristic pose, holding their abdomen curved underneath the body.

Sicus ferrugineus

The other species was Physocephala rufipes, another of the thick-headed flies. As with the species above, this is another bumblebee parasitoid, with the adults visiting flowers. The thin waist, yellow and black face pattern and bulbous ending to the abdomen makes this a distinctive species.

Physocephala rufipes