Anasimyia contracta
Anasimyia contracta is a European species of hoverfly. Description
The wing length 5 to 7.5 mm. Tergite 2 is narrower than it is long and it has greyish 'hockey stick' shaped markings. A. transfuga has similar markings but with tergite 2 parallel sided and wider than long. Habits
A wetland species found near ponds with Typha, especially in fens. Flowers visited include white umbellifers, Menyanthes, Ranunculus, Myosotis, Potentilla palustris, Sorbus aucuparia and Potentilla palustris 
The larva has been found among debris of dead Typha stalks beneath the water surface. Distribution
West Palearctic Ireland eastwards through central Europe to European Russia. References

Muscomorph flies of Europe
Eristalini
Insects described in 1980