Variable Wasp Hoverfly
Another busy day, with an early morning visit to Thorpe Wood for my fifth bird transect of the season. At least there was no frost, though the vegetation was quite waterlogged thanks to overnight rain. The droplets of rain and the low morning sun brought out the delicate beauty of wood millet - a very graceful grass indeed.
After breakfast I met up with Chris to carry out a last scoping visit at Barnack Hills and Holes, before the Fen Edge Holiday. We were pleased to see that a few more plants had come into flower, including Purple Milk-vetch and the first Man orchids. The sunshine even brought out a few invertebrates - we spotted three Green Hairstreaks and a few other assorted insects including this very smart Variable Wasp Hoverfly Chrysotoxum elegans, which was a bit too cold to fly away.
This wasp-mimic is Nationally Scarce and is most often found near the coast in south-western England and southern Wales, but also occurs on on chalk and limestone grassland further east. We don’t know much about the behaviour of its larvae, but species in this genus are thought to be associated with ants’ nests, in which the hoverfly larvae possibly feed on the root aphids being farmed by the ants for their honeydew.