Stable flies, Face flies and House flies

Family Muscidae

Identification

Small to rather large flies, often resembling house flies. Second antennal segment cleft; vein Cu₁ + 1A not reaching margin of wing; lower calypterae nearly always longer than upper one; prosternum sclerotized.

Includes the genera Stomoxys, Lyperosia and Haematobia in which both sexes feed on mammalian blood. Also many other genera which do not feed on blood such as Musca, although some feed on body secretions. The larvae of most species are saprophagous, whilst some are carnivorous.

Stomoxys calcitrans (Stable fly)

Identification & Distribution:

Body length 4-7 mm; mouthparts extended forwards as a long piercing proboscis; palps less than one third the length of the proboscis; gray in colour with four black stripes on the thorax; characteristic pattern of dark spots on the second and third abdominal segments - one marked median spot and two lateral round spots. Distributed worldwide having been introduced to North America in the 1700s.

Biology & Disease Transmission: Important biting insect pests of livestock especially cattle and horses, but will feed on a wide range of vertebrate hosts including man, birds and reptiles. Main harm is through disturbance of feeding, but may also be a disease vector especially of mastitis in dairy cattle herds.

These are two female Stomoxys calcitrans, the first sunbasking near cattle and the second having inadvertently flown into a house in Dorset. Note the long piercing proboscis and the pattern of dark spots on the abdomen. Stable flies are important pests of cattle and numbers present in an area are commonly monitored with sticky panels.

This shows the catch - here a mixture of tsetse flies (Glossina austeni) and Stomoxys - being removed from a sticky panel used to sample biting flies in Bodhai in the Garissa district of Kenya. Beresford & Sutcliffe (2008) working on a dairy farm in Canada have demonstrated the critical importance of the height of the sticky trap above the vegetation in determining catch size.

Musca autumnalis (Face fly)

Identification & Distribution:

Both sexes have red eyes, a grey thorax with four black stripes and wings tinted orange towards the base. Abdomen more rounded than Musca domestica. Male has black abdomen with bright orange patch on each side; female is has a grey and black checkerboard of patches. Distributed through most of Europe, central Asia through to north India and China and parts of North Africa; introduced to North America in the 1940s.

Biology & Disease Transmission:

Very common around cattle and horses. Larvae develop in cow pats; adults feed on secretions from eyes and nose of cattle and horses and occasionally on blood exuding from horse fly bites. As well as disturbance to feeding (especially to horses), face flies can transmit the eyeworm Thelazia rhodesi to cattle and horses, and the bacterium Moraxella bovis, which causes infectious bovine keratoconjunctivitis ('pink eye') in cattle. Also implicated as a vector of the bacterium Corynebacterium pyogenes which causes mastitis.

The first image shows a male and the second a female. Both were sun basking on a fence in a group of about ten flies. Such aggregations are not uncommon with this species and presumably facilitate mating.

The images show faceflies and other muscids feeding on secretions from the eyes and nose of cattle. Various methods of insecticidal control have been used, but they are all only partially effective (Thomas & Jesperson, 1994).

Musca domestica (House fly)

Identification & Distribution:

Both sexes have red eyes, a grey thorax with four narrow black stripes, a sharp upward bend in the fourth longitudinal wing vein, and a pointed elongate abdomen (relative to Musca autumnaria). Male has a yellowish abdomen with dark dark midline and some irregular dark markings on the sides; female has a grey and black checkerboard of patches. Distributed worldwide.

Biology & Disease Transmission: Usually found in close association with humans or human activities. Feeds and oviposits on decomposing and rotting organic matter and settles on humans, their food and utensils. A common pest of pig and poultry farms as well as horse stables and cattle barns. Has the potential to distribute hundreds of different pathogenic organisms and known to transmit many of them including Salmonella, Shigella and Campylobacter. Most commonly linked to outbreaks of diarrhoea and shigellosis, but also other diseases such as typhoid fever and anthrax. Houseflies also carry the eggs and cysts of many intestinal worms, including Ascaris spp., hookworms and tapeworms.

This image shows a male house fly sitting on the work surface in a kitchen. The main method of fly control is good sanitation, but insecticides and traps may also be useful.

Identifications & Acknowledgements Whilst we try to ensure that identifications are correct, we do not warranty their accuracy. We have mostly made identifications from our photos of living specimens. Any errors in identification or information are ours alone, and we would be very grateful for any corrections. Most of the taxonomic information on families is summarized from Richards & Davies (1977). Muscid identification was done using characters given by d'Assis-Fonseca (1968)

References  d'Assis-Fonseca, E.C.M. (1968). Diptera Cyclorrapha Calyptrata: Muscidae. Handbooks for the Identification of British Insects. 10. Royal Entomological Society of London, London.  Beresford, D.V. & utcliffe, J.F. (2008). Stable fly (Stomoxys calcitrans: Diptera, Muscidae) trap response to changes in effective trap height caused by growing vegetation. Journal of Vector Ecology 33 (1),40-45. Full Text  Richards, O.W. & Davies, R.G. (1977). Imms' General Textbook of Entomology. 10th Edn. Chapman & Hall, London.  Thomas, G. & Jesperson, J.B. (1994). Non-biting Muscidae and control methods. Revue scientifique et technique (International Office of Epizootics) 13 (4), 1159-1173. Full Text

Last updated 3 January 2013