Root-Maggot Fly
Anthomyia ?
This insect is about 4mm in length. It appears to be a platypezid. Observed in a small-scale garden at Eldoret, Kenya, January 2012.
Most Anthomyiids are associated with moist, decopmposing vegetation. Many others are able to feed on the roots of living plants. Most are drab gray in color, but others like this one are boldly marked black and white.