A male Eristalis pertinax (Diptera: Syrphidae). This species is distinguished from the other similar Eristalis tenax and Eristalis similis by its orange front tarsi. A male because its eyes meet on top of its head.
For a top view of another male of this species see here.
Photos taken in Whiteknights Park, Reading University grounds, Reading, on 2010-07-30.