Thursday 8 May 2014

End April 2014

The second half of April has not been as productive for hoverflies for me. Our first Diptera Group meeting of the year at Ditchford Lakes and Meadows only produced three species. The near ubiquitous Melanostoma scalare was swept from near a hedgerow. Anasimyia transfuga was swept off lakeside reed grasses and a single Lejogaster metallina was swept out of the wet marshy area in the meadow. I found my first big-headed fly (Pipunculidae) of the year here - Dorylomorpha haemorrhoidalis. This area was much more productive for dung flies and their allies (Scathophagidae). Sweeping over the really wet areas produced Scathophaga stercoraria, S. inquinata, S. suilla, S. furcata, Nanna inermis and Trichopalpus fraternus. Snail-killing flies (Sciomyzidae) in the marsh were the distinctive Sepedon sphegea and Elgiva solicita. Three empids Rhamphomyia crassirostris, R. sulcata and R. pilifer and a few common craneflies made for a good start to our field meetings.

Pete Sharp gave me a parasitic fly (Tachinidae) that he had raised from the pupa of lunar yellow underwing Noctua orbona taken at Lakenheath in Suffolk on 12th April. It turned out to be Pales pavida. The lunar yellow underwing is not listed as a host for this fly but other Noctua species are given. I am always happy to try to identify parasitic flies that the lepidopterists find when raising larvae. Pete has provided me with some good records of parasitic flies and their hosts and I pass on all the details to the Tachinid Recording Scheme.

The Pitsford Reserve moth traps are yielding a good number of flies now. Craneflies seem particularly attracted to the lights and up to the end of April there had been several Tipula oleracea and T. vittata. The small cranefly Trimicra pilipes was taken several times in the trap by the water's edge. This distinctive species has very hairy legs, particularly in the male. It is associated with draw-down zones of water bodies so Pitsford is probably an ideal habitat for it.