Orthonevra geniculata
Orthonevra geniculata is a species of hoverfly found in the Palearctic.

Description
External images
For terms see Morphology of Diptera
Wing length 4·5-5·5 mm. Face with triangular white marks. Legs yellow. Wing vein r-m brown. Pterostigm bicolorous: pale with dark area at base. Maibach et al. (1994) figure the male terminalia. 
See references for determination.

Distribution
Palearctic North Norway to Belgium. Ireland East through North Europe and Central Europe. North Italy. European Russia to the Russian Far East, Siberia and Mongolia.

Biology
Habitat: Quercus forest (beside springs, flushes and brooks). Alnus and Salix habitats carr, fen and margins of raised bogs. Flowers visited include Anemone nemorosa, Bellis, Caltha, Cardamine, Malus sylvestris, Menyanthes, Prunus spinosa, Ranunculus, Salix,

The flight period is mid April  to mid May.The larva is associated with springs and wet flushes.

References

Diptera of Europe
Brachyopini
Insects described in 1822
Taxa named by Johann Wilhelm Meigen