Calliphoridae

"Blowfly" redirects here. For the rapper, see Blowfly (artist).

Blow-fly
Blowfly
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Diptera
Suborder:	Brachycera
Infraorder:	Muscomorpha
Subsection:	Calyptratae
Superfamily:	Oestroidea
Family:	Calliphoridae
Subfamilies
Calliphorinae Chrysomyinae Luciliinae Polleniinae Melanomyinae

Blow-flies (also frequently spelled blow flies or blowflies) are members of the family Calliphoridae of flies (Diptera). Flies in this family are often metallic in appearance and between 10 to 12mm in length.

Some members of this family are known as bluebottles, clusterflies or greenbottles. The name blow-fly comes from an older English term for meat that had eggs laid on it, which was said to be fly blown. The first association of the term “blow” with flies was used by Shakespeare in his plays Loves Labour Lost, The Tempest, and Antony and Cleopatra.

Blow-flies are usually the first insects to come in contact with carrion because they have the ability to smell death from up to ten miles away. Upon reaching the carrion, females deposit eggs onto the body. Forensic entomologists have begun to use the information to determine a person’s time of death at crime scenes.

Description

Characteristics

Calliphoridae adults are known for being shiny with metallic coloring, often with blue, green, or black bodies. Antennae are 3-segmented, aristate. The arista are plumose the entire length, and the second antennal segment is distinctly grooved. Members of Calliphoridae have vein Rs 2-branched, frontal suture present, and well developed calypters.

The characteristics and arrangement of hairs are used to tell the difference between members of this family. All blow-flies have bristles located on the meron. Having two notopleural bristles and a hindmost posthumeral bristle located lateral to pre-sutural bristle are characteristics to look for when identifying this family.

The thorax has the continuous dorsal suture across the middle, along with well defined posterior calli. The post-scutellum is absent or weakly developed. The costa is unbroken and the sub-costa is apparent on the insect.

For a pictorial atlas explaining these terms go to [1]

1. Key to the Calyptrate families
2. Useful site for diagnostic features. (In French
3. Japanese Calliphoridae

Development

The Australian Sheep Blowfly, Lucilia cuprina

Close-up of the head of a blow-fly

A Chrysomya albiceps fly

Most species of blowflies studied thus far are anautogenous; a female requires a substantial amount of protein to develop mature eggs within her ovaries (about 800 µg per pair of ovaries in Phormia regina). The current theory is that females visit carrion both for protein and egg laying, but this remains to be proven. Blow-fly eggs,usually yellowish or white in color, are approximately 1.5 mm x 0.4 mm, and, when laid, look like rice balls. While the female blow-fly typically lays 150-200 eggs per batch, she is usually iteroparous, laying around 2,000 eggs during the course of her life. The sex ratio of blowfly eggs is usually 50:50, but one interesting exception is currently documented in the literature. Females from two species of the genus Chrysomya (C. rufifaces and C. albiceps) are either arrhenogenic (laying only male offspring) or thelygenic (laying only female offspring).

Hatching from an egg to the first larval stage takes about 8 hours to one day. Larvae have three stages of development (called instars); each stage is separated by a molting event.The instars are separable by examining the posterior spiracles, or openings to the breathing system [2]. The larvae use proteolytic enzymes in their excreta (as well as mechanical grinding by mouth hooks) to break down proteins on the livestock or corpse they are feeding on. Blowflies are poikilothermic, which is to say that the rate at which they grow and develop is highly dependent on temperature and species. Under room temperature (about 30 degrees celsius) the black blowfly Phormia regina can go from egg to pupa in 150-266 hours (6 to 11 days). When the third stage is complete the pupa will leave the corpse and burrow into the ground, emerging as an adult 7 to 14 days later.

Food Sources

Adult blow-flies are occasional pollinators, being attracted to flowers with a strong odor resembling rotting meat, such as the American pawpaw or Dead Horse Arum. There is little doubt that these flies utilize nectar as a source of carbohydrates to fuel flight, but just how and when this happens is unknown. One study has been done to prove that the visual stimulus a blow-fly receives from its compound eyes is what is responsible for causing its legs to retract from their flight position and allow it to land on any surface.

Larvae of most species are scavengers of carrion and dung and most likely constitute the majority of the maggots found in such material, although it is not uncommon for them to be found in close associate with other dipterous larvae from the families Sarcophagidae, Muscidae, and many other acalyptrate muscoid flies.

Diversity

Worldwide, there are 1100 species of blowflies, with 228 species in the Neotropics, but very numerous species in Africa and Southern Europe. The most common area to find Calliphoridae species are in the countries of India, Japan, Central America, and Southern United States.

The typical habitat for blow-flies are temperate to tropical areas that provide a layer of loose, damp soil and litter where larvae may thrive and pupate.

Economic Importance

Myiasis

Blowflies have caught the interest of researchers in a variety of fields, although the large body of literature on calliphorids has been concentrated on solving the problem of myiasis in livestock. It is estimated that the sheep blowfly Lucilia cuprina causes the Australian sheep industry over $170 million a year in losses. While much of the biology of these flies has been studied in the laboratory, the natural life history of the blowflies remains a largely untapped body of research.

Screwworms

The Primary Screwworm (Cochliomyia hominivorax) once a major pest in southern United States, has been eradicated through massive release of sterilized males. See Sterile insect technique.

Maggot Therapy

MDT or Maggot Debridement Therapy is the medical use of selected, tested and disinfected fly larvae, including blow-fly maggots, for cleaning non-healing wounds. Lucilia sericata (Phaenicia sericata), or the common green bottle fly, is the preferred species of maggot used for maggot-debridement also, called Maggot therapy. Medicinal maggots do three things: clean out wounds by eating away the dead, infected tissue, kill off the bacteria, and stimulate wound healing. One problem with this type of therapy is that some species of flies eat healty tissue, as well. This type of therapy can be used to treat pressure ulcers, diabetic foot wounds, venous stasis ulcers and post surgical wounds.

To view actual cases where maggot therapy is used go to:

http://www.ucihs.uci.edu/som/pathology/sherman/cases.htm

Disease

Adults may vector pathogens of diseases such as dysentery.

Forensic Importance

Since development is highly predictable if the ambient temperature is known, blow-flies are considered a valuable tool in forensic science. Traditional estimations of time since death (namely rigor mortis and algor mortis) are generally unreliable after 72 hours and often entomologists are the only officials capable of generating an accurate approximate time interval. The specialized discipline related to this practice is known as forensic entomology [3]

Calliphora vicina and Cynomya mortuorum are important flies of forensic entomology.

Calliphora augur

Other forensically important Calliphoridae are Phormia regina, Calliphora vomitoria, Calliphora livida, Lucilia cuprina, Lucilia sericata, Lucilia illustris, Chrysomya rufifacies, Chrysomya megacephala, and Cochliomyia macellaria. One interesting myth states that species from Lucilia can sense death and show up right before it even occurs.

Pest control

In order to reduce the number of blowflies entering the home, a number of procedures can be adopted; these include: Improving sanitation, using sprays and poisons.

Improved sanitation

Improving the sanitary levels within, and outside the home will go a long way to destroying the habitat in which the blowflies thrive.

In order to reach this goal certain rules of thumb should be followed. Firstly, ensure that all scraps of food – especially fruit, vegetables and meat – are discarded properly. It’s preferable to place these scraps into a sturdy dustbin or trash can with a tight fitting lid; by storing those in this way the vessels are less likely to be knocked over by scavenging animals, thus not exposing the contents to the elements and even more, the blowflies.

Secondly, it must be noted that the bins should be situated as far away from the premises as possible. This will limit the chance of other pests entering your home - once they realize they can’t get at the contents of the said bins.

Additionally, cleaning methods should be put into play when combating this particular kind of pest. Not only must care be taken in ensuring the inside of the bins are regularly cleaned but more importantly their outsides and the immediate area surrounding too.

Identification

• Fritz Konrad Ernst Zumpt Calliphorinae, in Lindner, E. Fliegen Palaearkt. Reg. 64i, 140 p. (1956)
• Fan, C.T. Key to the common synanthropic flies of China. Peking [= Beijing]. xv + 330 p. In Chinese but really excellent illustrations. (1965).
• Kano, R. and Shinonaga, S. Calliphoridae (Insecta: Diptera) (Fauna Japonica) , Tokyo Biogeographical Society of Japan, Tokyo.( 1968). In English.
• Lehrer, A.Z., Diptera. Familia Calliphoridae. In: Fauna R.S.R., Insecta, vol. XI,(12), Edit. R.S.R., Bucuresti, 1972, 245 p. In Romanian.
• Rognes, K. Blowflies (Diptera: Calliphoridae) of Fennoscandia and Denmark. Fauna Entomologica Scandinavica, Volume 24.
• E. J. Brill/Scandinavian Science Press Ltd. Leiden.(1991).

Genera and Species

According to Keys to the Genera and Species of Blow Flies (Diptera: Calliphoridae) of America North of Mexico by Terry Whitworth

 · Bellardia

Bellardia bayeri

Bellardia vulgaris

 · Calliphora – Blue bottle flies, Bluebottles

Calliphora alaskensis

Calliphora aldrichia

Calliphora coloradensis

Calliphora genarum

Calliphora grahami

Calliphora latifrons

Calliphora livida

Calliphora loewi

Calliphora montana

Calliphora stelviana

Calliphora vicina

Calliphora terraenovae

Calliphora vomitoria

 · Cyanus

Cyanus elongate

 · Cynomya

Cynomya cadaverina

Cynomya mortuorum

 · Chloroprocta

Chloroprocta idioidea

 · Chrysomya – Old World screw-worms

Chrysomya megacephala

Chrysomya rufifacies

 · Cochliomyia – New World screw-worms

Cochliomyia aldrichi

Cochilomyia hominivorax

Cochilomyia macellaria

Cochilomyia minima

 · Compsomyiops

Compsomyiops callipes

 · Phormia

Phormia regina - Black blow-fly

 · Protocalliphora

Protocalliphora beameri

Protocalliphora bennetti

Protocalliphora bicolor

Protocalliphora hirundo

Protocalliphora interrupta

Protocalliphora metallic

Protocalliphora parorum

Protocalliphora bennetti

Protocalliphora rugosa

Protocalliphora sapphire

Protocalliphora sialia

Protocalliphora occidentalis

 · Protophormia

Protophormia atriceps

Protophormia terraenovae

 · Trypocalliphora

Trypocalliphora braueri

 · Lucilia – Greenbottles

Lucilia cluvia

Lucilia coeruleiviridis

Lucilia cuprina

Lucilia elongata

Lucilia eximia

Lucilia illustris

Lucilia magnicornis

Lucilia mexicana

Lucilia sericata

Lucilia silvarun

Lucilia thatuna

 · Melondexia

Species still to be determined

 · Pollenia – Cluster flies

Pollenia angustigena

Pollenia griseotomentosa

Pollenia labialis

Pollenia pediculata

Pollenia rudis

Pollenia vagabunda

 · Angioneura

Five species

 · Opsodexia

Four species

External links

• Calliphoridae Taxonomy Central
  • Family description and images
• Template:PDFlink
• Image Gallery
• OPH Good Housekeeping - Pest Control