The Common Housefly and the Lesser Housefly are the most widespread household flies. The adult is 7-8mm long, grey in colour with black stripes on the back, with a single pair of veined membraneous wings. The large compound eyes take up most of the head and are wider apart in the female than the male of the species. The smaller Lesser Housefly, rejoicing in the scientific name Fannia canicularis, is the one that cruises around light fittings, abruptly changing direction in mid-flight.