Description:
Syrphus ribesii (in Dutch: Bessenbandzweefvlieg) is very similar in appearance to Syrphus vitripennis (in Dutch: Kleine Bandzweefvlieg) and Syrphus torvus (in Dutch: Bosbandzweefvlieg).
These 3 hoverflies are almost impossible to distinguish from a photo.
The female Syrphus ribesii can be distinguished by Syrphus vitripennis by having entirely yellow femorae (thighs) whereas Syrphus vitripennis has almost entirely black thighs, and from Syrphus torvus by having no hairs present in their eyes.
The male Syrphus ribesii also has bare eyes, unlike Syrphus torvus, but is extremely similar to Syrphus vitripennis, differing only in having some black hairs present on the hind femur (thigh) and in having the second basal cell of the wing entirely covered by small hairs (microtrichia).
1st photo: A female. In my yard, Hilversum, The Netherlands, 3 September 2012
2nd, 3rd & 4th photo: A female. Houten, The Netherlands, 18 August 2011