This specimen appears to be a Tabinidae, commonly called a March fly. These species 'bite' people with a painful impact as they go in search of a blood meal. Similar body colouration to Calliphoridae, but the green eyes usually separates Tabinids from Calliphorids which usually have red eyes. Also, Calliphorids are carrion flies which have siphon-like mouthparts, and are noisy in flight. Tabinids are mostly quiet in flight, which is why the bite is usually the first indication of their presence.