All yellow legs make this species relatively easy to identify.
Brief description of what you observed
Adult. Resting on flower. Garden. Photo taken.
(live oak/chaparral habitat).
ID by Martin Hauser @ BugGuide.
Syrphus is a genus of hoverflies. It can be distinguished from other genera of the tribe Syrphini because it is the only genus that has long hairs on the upper surface of the lower lobe of the calypter. (as well as hairs on the rear margin of the calypter as in most Syrphini)