Chalcosyrphus satanica

Chalcosyrphus (Xylotomima) satanica, the devil's leafwalker, is a rare species of syrphid fly collected in California. Hoverflies can appear nearly motionless while in flight. The adults, also  known as flower flies for they are commonly found around and on flowers from which they get both energy-giving nectar and protein rich pollen.

Distribution
United States.