Adults are medium-sized to small and usually have mainly dark body and leg colours.

Males congregate in characteristic dancing swarms beneath trees; females are more retiring in habit.

Larvae are characterised by their flattened bodies with striking lateral protuberances, and live as scavengers in various kinds of decaying organic matter.

The lesser housefly Fannia canicularis is a worldwide synanthropic species.

The Fanniidae were once a subfamily of Muscidae from which they may be distinguished by: References to identify the family include: