The smallest of the biting muscids, approximately 4.0mm long. Eggs are laid on fresh faeces, these hatch quickly and can mature in 4 days The pupal period is 6-8 days, they emerge and seek cattle.
Adults remain on host, females only leave to lay eggs on faeces.
Often occur in large numbers, when not feeding they rest around the horn region. Large numbers cause skin irritation and wounds by them may attract myasis producing flies. Intermediate host of Stephanofilaria stilesi a parasite of cattle in North America Control use to be by use of pour-ons, backrubbers and face powder bags. These applicators are placed so animals cannot avoid coming into contact with it, such as at a gate through which animals pass Click here for image of self-applicator Control of Horn fly using ear tags has been extremely successful. The use of Organophosphates and piperonyl butoxide as a synergist could be alternated with pyrethroid my help slow resistance.