''Calliphora livida'' is a member of the family

Calliphoridae The Calliphoridae (commonly known as blow flies, blow-flies, carrion flies, bluebottles, greenbottles, or cluster flies) are a family of insects in the order Diptera, with almost 1,900 known species. The maggot larvae, often used as fishing b ...

, the blow flies. This large family includes the genus ''

Calliphora ''Calliphora'' is a genus of blow flies, also known as bottle flies, found in most parts of the world, with the highest diversity in Australia. The most widespread species in North America area '' Calliphora livida'', '' C. vicina'', and '' C. v ...

'', the "blue bottle flies". This genus is important in the field of

forensic entomology Forensic entomology is the scientific study of the colonization of a dead body by arthropods. This includes the study of insect types commonly associated with cadavers, their respective life cycles, their ecological presences in a given environme ...

because of its value in

post-mortem interval The post-mortem interval (PMI) is the time that has elapsed since an individual's death. When the time of death is not known, the interval may be estimated, and so an approximate time of death established. Postmortem interval estimations can ra ...

estimation.

Taxonomy

''Calliphora livida'', known as the slow-flying and loud-buzzing blue bottle fly, was first discovered by

Jean-Baptiste Robineau-Desvoidy André Jean Baptiste Robineau-Desvoidy (1 January 1799 in Saint-Sauveur-en-Puisaye – 25 June 1857 in Paris) was a French physician and entomologist specialising in the study of Diptera (flies) and to some extent of the Coleoptera (beetles). ...

who originally thought ''C. livida'' was part of the species ''Calliphora viridescens''. Robineau-Desvoidy described ''C. viridescens'' in 1830, but it was not until 1948 that ''C. livida'' was described as a separate species; in 1948, D. G. Hall introduced one of the first textbooks of

entomology Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arach ...

, where he described a number of new species including ''C. livida''. ''C. livida'' is also very similar to the species '' C. coloradensis'', which when suffering from

teneral Ecdysis is the moulting of the cuticle in many invertebrates of the clade Ecdysozoa. Since the cuticle of these animals typically forms a largely inelastic exoskeleton, it is shed during growth and a new, larger covering is formed. The remnant ...

has similar genal dilation.

Description

Life cycle and reproduction

Blue bottle flies have a life cycle of approximately 15–36 days. The ''

'' species also have an optimal growth temperature from .Brundage, Adrienne. Forensic Entomology Instructor Araceli Palacios. 23 March 2009.

Developmental Stages

The egg is the first stage in the life cycle of a fly. The female extends structures called telescoping segments on her abdomen to lay eggs. ''C. livida'' eggs are identified as being less than in length, without pronounced flanges or longitudinal ridges, and with the arms of the flanges straight or slightly diverging. The egg stage is followed by the larval stage. Calliphorid flies have three

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. Th ...

instars An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or ass ...

lasting 421 days in all. Larvae in the genus ''Calliphora'' can be characterized by being round in cross section, slightly raised posterior spiracles which are surrounded by 10 or more tubercles, complete peritremes, and an accessory oral sclerite. '' C. vicina'', a close relative to ''C. livida'', has larval growth estimated to be at . The minimum developmental temperature is approximately and 4700 accumulated degree hours (ADH) are required for development from the moment the egg hatches to

pupa A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...

tion. When larvae have completed all three instars or become disturbed, they enter the pupal stage. Calliphorid flies disperse an average of before

pupation A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in the ...

and remain in the pupal stage for 3–20 (or more) days. The morphology of the puparia of ''C. livida'' is described as 25 globules occurring on the first abdominal segment on the bubble membrane.

Adult

Adult ''C. livida'' have a blue metallic sheen dulled by micromentum, or dense, tiny hairs. ''C. livida'' can be easily confused with ''C. coloradensis''; ''C. livida'' is distinguished by a black genal dilation (the cheek area of the fly) as opposed to a red genal dilation as found on ''C. coloradensis''. This characteristic is good to use for identification in fully sclerotized specimens but can be misleading in

flies, which are common in ''C. coloradensis''. Blue bottle flies are around in length, making them appear robust. ''C. livida'' has three postsutural intra-alar

seta In biology, setae (singular seta ; from the Latin word for "bristle") are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Annelid setae are stiff bristles present on the body. T ...

e, a characteristic shared with ''C. coloradensis'' and some ''C. latifrons''.

Distribution and diet

''C. livida'' is widespread over North America. These flies prefer shady locations, and tend to be found in significantly lower temperatures from . Calliphorid flies are attracted to

carrion Carrion () is the decaying flesh of dead animals, including human flesh. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures ...

and

excrement Feces ( or faeces), known colloquially and in slang as poo and poop, are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relati ...

. ''C. livida'' has been shown to arrive on carrion after a delay of about 24 hours.

Importance

Forensic science

''Calliphora livida'' holds great importance to

, which is the crossover between

arthropod Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arth ...

science and the

judicial system The judiciary (also known as the judicial system, judicature, judicial branch, judiciative branch, and court or judiciary system) is the system of courts that adjudicates legal disputes/disagreements and interprets, defends, and applies the law ...

. More importantly, ''C. livida'' plays a major role in the branch of medicocriminal forensic entomology, the use of

evidence to aid in solving usually violent crimes.

Flies Flies are insects of the Order (biology), order Diptera, the name being derived from the Ancient Greek, Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwing ...

and their

e can be used as

evidence Evidence for a proposition is what supports this proposition. It is usually understood as an indication that the supported proposition is true. What role evidence plays and how it is conceived varies from field to field. In epistemology, eviden ...

in such cases and with proper evaluation a

(PMI) can be given. A post-mortem interval, or time of death, is the main way flies and larvae contribute to these cases. Flies and fly larvae are beneficial because they undergo a certain life cycle that follows particular stages within a given time, depending on the environment. Due to this knowledge, entomologists can gather specimens and evaluate, based on the life cycle and knowledge of colonization, approximately how long an individual has been dead. The family

is one of the most important in forensic use due to their strong attraction to flesh. They are usually the first to arrive and colonize a body. ''C. livida'' along with ''

Phormia regina ''Phormia regina'', the black blow fly, belongs to the blow fly family Calliphoridae and was first described by Johann Wilhelm Meigen. The black blow fly's wings are specialized with a sharp bend. These flies are also have well-developed caly ...

Calliphora vomitoria ''Calliphora vomitoria'', known as the blue bottle fly, orange-bearded blue bottle, or bottlebee is a species of blow fly, a species in the family Calliphoridae. ''Calliphora vomitoria'' is the type species of the genus ''Calliphora''. It is c ...

, Calliphora livida, Lucilia cuprina,

Lucilia sericata The common green bottle fly (''Lucilia sericata'') is a blowfly found in most areas of the world and is the most well-known of the numerous green bottle fly species. Its body is in length – slightly larger than a house fly – and has brilli ...

, Lucilia illustris,

Chrysomya rufifacies ''Chrysomya rufifacies'' is a species belonging to the blow fly family, Calliphoridae, and is most significant in the field of forensic entomology due to its use in establishing or altering ''post mortem ''intervals. The common name for the spe ...

Chrysomya megacephala ''Chrysomya megacephala'', more commonly known as the oriental latrine fly or oriental blue fly, is a member of the family Calliphoridae (blowflies). It is a warm-weather fly with a greenish-blue metallic box-like body. The fly infests corpses s ...

Cochliomyia macellaria ''Cochliomyia macellaria'', also known as the secondary screwworm, is a species of blow fly in the family Calliphoridae. These screwworms are referred to as "secondary" because they typically infest wounds after invasion by primary myiasis-ca ...

, and

Protophormia terraenovae ''Protophormia terraenovae'' is commonly called northern blowfly, blue-bottle fly or blue-assed fly (blue-arsed fly in British English). It is distinguished by its deep blue coloration and large size and is an important species throughout the N ...

Calliphora vicina ''Calliphora vicina'' is a member of the family Calliphoridae, which includes blow flies and bottle flies. These flies are important in the field of forensic entomology, being used to estimate the time of a person's death when a corpse is foun ...

and Cynomya mortuorum'' are common species of blow flies often used to estimate a time of death.Brundage, Adrienne (13–15 February 2008). "Calliphoridae". Texas A&M University, College Station.

Post-mortem interval

''Calliphora livida'' is important in estimating

because of its relatively early appearance on

. ''C. livida'' is normally active during the springtime, but can also be found during the colder months. However, the most important indication of the post-mortem interval is the appearance of

e. Eggs that have been laid on the

by the adult blow fly hatch within a 24- to 48-hour period. These larvae then have three

instar An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow o ...

s, or developmental stages, in which they grow and decompose the body. The three instars occur throughout a period of 4 to 15 days depending on the amount of calories that can be amassed by a

maggot A maggot is the larva of a fly (order Diptera); it is applied in particular to the larvae of Brachycera flies, such as houseflies, cheese flies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and crane flies. E ...

. The three instars can be differentiated by the amount of slits there are in the spiracle of the maggot. The next phase of development in ''C. livida'' is the pupa, which lasts from 3 to 13 days. The length of

can be determined by color changes in the

from light to dark. The development of ''C. livida'' is very useful in determining post-mortem interval estimations because it is possible to determine relatively precise estimations based on a specific instar. Temperature, heat generated by the maggot mass, the type of food source, contaminants and toxins, and obstructions that thwart the oviposition of adults are all factors that can affect the rate of development of larvae, thereby effecting the estimation.

Medical/economic

While

flies Flies are insects of the Order (biology), order Diptera, the name being derived from the Ancient Greek, Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwing ...

and

e can be beneficial to humans through the

, they can also do a lot of harm. Flies can act as a

vector Vector most often refers to: *Euclidean vector, a quantity with a magnitude and a direction *Vector (epidemiology), an agent that carries and transmits an infectious pathogen into another living organism Vector may also refer to: Mathematic ...

for carrying

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...

on or in their body and then can deposit these germs on or near humans. Members of the genus ''

'' have been found to spread a number of bacterial diseases including

poliomyelitis Poliomyelitis, commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 70% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe sym ...

and

dysentery Dysentery (UK pronunciation: , US: ), historically known as the bloody flux, is a type of gastroenteritis that results in bloody diarrhea. Other symptoms may include fever, abdominal pain, and a feeling of incomplete defecation. Complication ...

and can cause

myiasis Myiasis is the parasitic infestation of the body of a live animal by fly larvae (maggots) which grow inside the host while feeding on its tissue. Although flies are most commonly attracted to open wounds and urine- or feces-soaked fur, some s ...

. Myiasis is the feeding of larvae on

necrotic Necrosis () is a form of cell injury which results in the premature death of cells in living tissue by autolysis. Necrosis is caused by factors external to the cell or tissue, such as infection, or trauma which result in the unregulated dig ...

tissue of a living organism. ''C. livida'' has been reported to cause myiasis, but it is not common for this species. ''C. livida'' can, however, be a vector for bacterial diseases and cause human illnesses.

Control and management

In 1950, a study was conducted in Savannah, Georgia on use of insecticides to control fly breeding in garbage cans. According to the study, BHC, or

lindane Lindane, also known as ''gamma''-hexachlorocyclohexane (γ-HCH), gammaxene, Gammallin and benzene hexachloride (BHC), is an organochlorine chemical and an isomer of hexachlorocyclohexane that has been used both as an agricultural insecticide and ...

, showed the best results for controlling the breeding of ''Calliphora livida''. Other materials that were used in the testing were

dieldrin Dieldrin is an organochloride originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to f ...

and

chlordane Chlordane, or chlordan, is an organochlorine compound that was used as a pesticide. It is a white solid. In the United States, chlordane was used for termite-treatment of approximately 30 million homes until it was banned in 1988. Chlordane was ...

, where the latter was shown to be the least effective. When the study was conducted again in 1951, PDB (paradichlorobenzene) crystals were shown to be a more effective pesticide than BHC. All materials tested seemed to be more effective towards blow flies than house flies.

References

{{Taxonbar, from=Q5022716 Calliphoridae Diptera of North America Forensic entomology Insects described in 1948