However there were a few birch trees that had been felled during the winter which were oozing sap from the stumps and this was attracting a few flies. Surprisingly, despite the cool temperature they were quite agile and difficult to catch. The most common species were Scathophagids, mainly the 'Yellow Dung Fly' Scathophaga stercoraria but a few more interesting species were seen.
Sepsids are small, shiny, ant-like flies. They have varying amounts of dusting on the sides of the thorax which are important identification features and the males have interesting armature on the front femurs. Species in the genus Sepsis all have a small blackish dot near the apex of the wing.
|Male Sepsis sp. showing spines and tubercles on the front femur and silvery dusting on the side of the thorax|
Also around the stumps were a number of cluster flies or blowflies (Calliphoridae). Species in the genus Pollenia were most frequent. These can easily be recognised as belonging to the genus as they have crinkly golden hairs beneath the black bristles on the thorax (although these do wear off and can become confined to the sides of the thorax only).
|Pollenia sp. The golden hairs have mainly worn off the top of the thorax but can still be seen on the sides|
Aside from the Scathophagids, Sepsids and Calliphorids, I saw a few Drosophilids (fruit flies) which will have to await identification when I have more time, and a Mycetophilid (fungus gnat) which evaded capture.
There was little else around. A couple of the birch-feeding Lygaeid bug Kleidocerys resedae were active and two Yellow Horned Achlya flavicornis moths were found at rest on an old birch stump.
Slim pickings and the subsequent weather has resulted in a return to the microscope.