Muscina
Encyclopedia
Muscina is a genus of flies that belongs to the family Muscidae
, currently consisting of 27 species. They are worldwide in distribution and are frequently found in livestock facilities and outside restrooms. The most common species are M. stabulans (the most widely studied species), M. levida, and M. prolapsa. Muscina flies commonly breed in manure and defecate on food, which has been linked to the spread of some disease and illnesses. The occurrence of Muscina larvae on dead bodies has led to their regular use in forensic investigations, as they may be used to estimate the time of death. Research have shown the prevalence of certain species of Muscina flies as vectors of diseases such as poliomyelitis
.
, sponging or sucking mouthparts, and a pale tip on the scutellum. The species M. stabulans and M. assimilis are larger than the housefly
, and have moderately curved fourth veins with the latter also having a black palpi. The species M. assimilis has legs that are entirely black. M. pascuorum flies have a red palpi, a strongly curved fourth vein that ends in or before the wing tip, and are generally larger than M. assimilis.
region, and a pale spot above the thorax
. These flies average 8 millimeters (0.3 inches) in length. The abdomen
of the false stable fly is either entirely black, or black with red sides. Its head ranges in color from a dark-grey to a whitish hue. Circular spiracular plates can be found separated by about one plate’s width in the posterior area.
The M. stabulans species were found in a study determining synanthropy (ecologically associated with humans) with the adult Muscidae
species collected in urban, rural and natural environments in Valdivia
, Chile
. According to the study, M. stabulans are mostly found in rural and natural neighborhoods, and rarely inhabit cities. The distribution of Muscina species tends to be spread throughout the United States. For the most part, Muscina stabulan is active year round, but fly activity tends to peak in the summer months, when the number of generation cycles also peak.
The habitat of the M. stabulans is similar to that of the house fly, Musca domestica. M. stabulans have been spotted in animal housing, such as poultry houses, as well as in the mucosal linings of mammalian intestines. M. stabulan can be found on carrions in the decomposition stages, but they exhibit a strong preference for the later stages of decomposition
. They are able to reach a buried body in shallow ground through several inches of dirt.
Diptera
. Flies in the Dipteran order undergo what is known as holometabolous transformation, a type of metabolic transformation in which an insect
starts out as an egg, undergoes larval stages, and then pupates before reaching full adulthood. The adult insect
is referred to as an imago
.
until all of the eggs are produced and then lays the eggs through an ovipositor
located on the hind end of the abdomen
.
These eggs are very small in size. Female adult flies usually choose decaying matter as sites to lay the eggs. These nutrient-rich areas are ideal for the growth and development of the hatching larva
e. In contrast to adult flies, the larvae do not have a definite head. Instead, there are two grasping hooks that they use to cut and tear food. The larvae of Muscina have 11 segments. At the posterior end of the larvae are a set of spiracles. The spiracles of Muscina have spiracular slits that are not straight and exhibit some form of curvature. Larvae use the spiracles to breathe. The spiracles have a number of slits that can be used to determine what instar
, or larval stage, the larvae is in; for example, one slit means first instar, two slits means second instar, and three slits means third instar. It has been shown that the environmental temperature has a strong influence on larval development: increasing temperature directly influences the amount of time that the larva
e need to complete development.
, which aids in protection of the vital organs of the fly. M. assimilis is a species in this genus
that does not form a cocoon. The duration of the pupal stage also varies depending on the temperature of the surrounding environment.
.
Some insects have been shown to be potential carriers of pathogenic agents that can cause diseases. Mosquitoes and ticks as well as certain species of Muscina flies have been revealed to be possible vectors. M. stabulans, along with almost two dozen other species of flies have been named the “disease-causing flies.” Species of flies such as M. stabulans can spread bacterial and viral
pathogens via transfer from its feet or mouthparts
. Adult female flies tend to lay eggs in decaying material such as food or dead organisms and fresh fecal material. The fecal material houses a vast number of pathogenic bacteria, viruses, protozoan and other disease-causing agents. Most of the bacteria and viruses are not introduced from the fecal material to the fly when in the egg or larva
e form; rather, the transfer occurs in the transition of a young fly to adulthood. Fecal particles attach to the fly’s outer body as it emerges from the larvae. Transfer of bacteria occurs when the fly takes off and lands on an open wound or food material. Physical contact flakes the pathogen
off the fly's body and causes contamination
. The spread of a pathogen
by means of a fly’s outer body, such as its feet, to the host, is referred to as mechanical transmission. It is possible to determine the identify pathogen
carried by identifying the species of fly. In these instances, food sanitation
is an important preventive measure to ensure food safety
. Moreover, a study of flies including M. stabulans and M. assimilis has shown that fly incidence peaked about 4–5 months before the occurrence of a poliomyelitis
epidemic. This time period matches the time it takes for the infective agent to incubate in a human plus the extra time necessary for the fly to acquire and incubate the virus in its body.
, and are commonly found on corpses, urine, and feces. Muscina flies are useful in determining post-mortem intervals. The presence of Muscina larva
e in diapers and on genitalia can indicate a timeline for the period of neglect in infant or elderly death cases. From the second instar
phase onwards, M. stabulans are predacious upon other larvae, and will eat other forensically important arthropods. Presence of the false stable fly larva
e on buried bodies enables investigators to estimate the time of death. The antennae
of the false stable fly can detect buried bodies. In these cases, the fly lays its eggs on top of the soil, and the hatching larvae will then burrow and invade the corpse. The false stable fly will also lay its eggs in blood
, even in the absence of a body. The presence of eggs in blood allows entomologists to estimate the time of injury, which helps investigators and crime scene investigators. Muscina stabulans are found on corpses in autumn and winter. In one experiment, M. stabulans larvae were found on a rabbit corpse two days after death. M. stabulans are present in the fresh stage, but are predominantly found in the adipocere
-like stage, characterized by the hydrolysis
of the carcass’ fatty tissue. In this phase, the carcass loses its shape and is a mass of hair, fat, skin, and cartilage
. The skin eventually becomes rigid, protecting the larva
e on the carcass and the insects living underneath the carcass.
is the feeding on live humans and vertebrate
s by dipterous
fly larvae.
was reported with a rare case of intestinal myiasis. Symptoms included abdominal discomfort, bloated abdomen, and intestinal hurrying after meals. His stool
sample was watery and contained sparse fecal matter, but it was littered with maggot
s. A repeat sample two hours later also displayed positive signs of maggots. The maggots were washed in 0.9% normal saline
solution and in distilled water and were subsequently preserved in 10% formalin before being submitted to the Vector Control Research Center (VCRC), Pondicherry, for definite species identification. Upon arrival, the maggots were rinsed again with distilled water and dropped into a solution of 10% sodium hydroxide for six hours. The last segment on the maggot was transected, and by using a Zeiss binocular dissection microscope, the spiracular plate was removed and placed in Hoyer’s medium. By attaching a camera to a MOTIC BA 300 digital compound microscope, pictures were taken of the whole larva and the spiracular plate. The maggots were approximately 6–7 mm length-wise and 1–1.5 mm in width and appeared a dullish-white in color. Their carcasses were coated with a tough integument consisting of multiple bands of minute, grayish-brown spines. Closer examination with a microscope revealed a total of 11 separate segments. Each segment, except for the anal segment, had a belt of small, well-developed spines going towards the posterior margins. The anterior and posterior regions were similarly narrow while the middle appeared broad. Two hooks were found on the pseudo-cephalic segment of the maggot
which enabled them to attach to the mucosal lining of the intestine. The appearance of spiracular slits on the solid plate on the peritreme of the posterior spiracle
narrowed the results down to the genus Muscina. The curve in the spiracular slit at the middle verified that the species was M. stabulans.
Muscina flies are rarely seen on the skin of living mammals, but there has been one reported case where a Muscina species alone caused cutaneous myiasis in a human. A nine-year-old girl from Minnesota
was reported with a lump on her wrist that was reddened and elevated, but showed no signs of any external openings or contains any pus inside. A vaseline bandage was applied after some blood was extracted, and the lump was soaked in hot water several times. Twelve hours later, a worm was found in the cut after removing the bandage. Several other small lesions were noticeable around the proximity of the cut, but they receded at about this time. The girl recovered after applying a hot pack to the lesion. The larvae were confirmed by M. T. James of the State College of Washington
and C. W. Sabrosky and W. W. Wirth of the United States National Museum to be a Muscina fly, most likely M. assimilis.
, Southern Africa
, and the British Isles
. M. pabulorum along with other dipteran flies have been identified in cases in southwestern Scotland
.
. M. stabulans show up during the adipocere
-like stage of decomposition whereby the carcass
loses its natural shape due to hydrolysis of the fatty tissue. Moreover, M. stabulans appearance on bodies in large numbers during the autumn and winter months is useful in narrowing down time of death.
Muscidae
Muscidae are a family of flies found in the superfamily Muscoidea. The apical segment of the antennae of Muscidae are plumose, and the basal portion is smooth....
, currently consisting of 27 species. They are worldwide in distribution and are frequently found in livestock facilities and outside restrooms. The most common species are M. stabulans (the most widely studied species), M. levida, and M. prolapsa. Muscina flies commonly breed in manure and defecate on food, which has been linked to the spread of some disease and illnesses. The occurrence of Muscina larvae on dead bodies has led to their regular use in forensic investigations, as they may be used to estimate the time of death. Research have shown the prevalence of certain species of Muscina flies as vectors of diseases such as poliomyelitis
Poliomyelitis
Poliomyelitis, often called polio or infantile paralysis, is an acute viral infectious disease spread from person to person, primarily via the fecal-oral route...
.
Characteristics
Muscina species are characterized by a retractable proboscisProboscis
A proboscis is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In simpler terms, a proboscis is the straw-like mouth found in several varieties of species.-Etymology:...
, sponging or sucking mouthparts, and a pale tip on the scutellum. The species M. stabulans and M. assimilis are larger than the housefly
Housefly
The housefly , Musca domestica, is a fly of the suborder Cyclorrhapha...
, and have moderately curved fourth veins with the latter also having a black palpi. The species M. assimilis has legs that are entirely black. M. pascuorum flies have a red palpi, a strongly curved fourth vein that ends in or before the wing tip, and are generally larger than M. assimilis.
Muscina stabulans
The species M. stabulans, more commonly known as the false stable fly, has partially reddish-brown legs, four characteristic dark stripes along the thoraxThorax
The thorax is a division of an animal's body that lies between the head and the abdomen.-In tetrapods:...
region, and a pale spot above the thorax
Thorax
The thorax is a division of an animal's body that lies between the head and the abdomen.-In tetrapods:...
. These flies average 8 millimeters (0.3 inches) in length. The abdomen
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
of the false stable fly is either entirely black, or black with red sides. Its head ranges in color from a dark-grey to a whitish hue. Circular spiracular plates can be found separated by about one plate’s width in the posterior area.
The M. stabulans species were found in a study determining synanthropy (ecologically associated with humans) with the adult Muscidae
Muscidae
Muscidae are a family of flies found in the superfamily Muscoidea. The apical segment of the antennae of Muscidae are plumose, and the basal portion is smooth....
species collected in urban, rural and natural environments in Valdivia
Valdivia, Chile
Valdivia is a city and commune in southern Chile administered by the Municipality of Valdivia. The city is named after its founder Pedro de Valdivia and is located at the confluence of the Calle-Calle, Valdivia and Cau-Cau Rivers, approximately east of the coastal towns of Corral and Niebla...
, Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
. According to the study, M. stabulans are mostly found in rural and natural neighborhoods, and rarely inhabit cities. The distribution of Muscina species tends to be spread throughout the United States. For the most part, Muscina stabulan is active year round, but fly activity tends to peak in the summer months, when the number of generation cycles also peak.
The habitat of the M. stabulans is similar to that of the house fly, Musca domestica. M. stabulans have been spotted in animal housing, such as poultry houses, as well as in the mucosal linings of mammalian intestines. M. stabulan can be found on carrions in the decomposition stages, but they exhibit a strong preference for the later stages of decomposition
Decomposition
Decomposition is the process by which organic material is broken down into simpler forms of matter. The process is essential for recycling the finite matter that occupies physical space in the biome. Bodies of living organisms begin to decompose shortly after death...
. They are able to reach a buried body in shallow ground through several inches of dirt.
Life cycle
Muscina species undergo the same transformations throughout the life cycle as similar species and families in the orderOrder (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Diptera
Diptera
Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
. Flies in the Dipteran order undergo what is known as holometabolous transformation, a type of metabolic transformation in which an insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
starts out as an egg, undergoes larval stages, and then pupates before reaching full adulthood. The adult insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
is referred to as an imago
Imago
In biology, the imago is the last stage of development of an insect, after the last ecdysis of an incomplete metamorphosis, or after emergence from the pupa where the metamorphosis is complete...
.
Eggs and larvae
Flies are completely wingless at the beginning of development. In normal fly production there can be as many as 250 eggs laid by a mature female. The adult female keeps the eggs inside the abdomenAbdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
until all of the eggs are produced and then lays the eggs through an ovipositor
Ovipositor
The ovipositor is an organ used by some animals for oviposition, i.e., the laying of eggs. It consists of a maximum of three pairs of appendages formed to transmit the egg, to prepare a place for it, and to place it properly...
located on the hind end of the abdomen
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
.
Larva
A larva 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...
e. In contrast to adult flies, the larvae do not have a definite head. Instead, there are two grasping hooks that they use to cut and tear food. The larvae of Muscina have 11 segments. At the posterior end of the larvae are a set of spiracles. The spiracles of Muscina have spiracular slits that are not straight and exhibit some form of curvature. Larvae use the spiracles to breathe. The spiracles have a number of slits that can be used to determine what instar
Instar
An instar is a developmental stage of arthropods, such as insects, between each molt , until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or assume a new form. Differences between instars can often be seen in altered body proportions, colors, patterns, or...
, or larval stage, the larvae is in; for example, one slit means first instar, two slits means second instar, and three slits means third instar. It has been shown that the environmental temperature has a strong influence on larval development: increasing temperature directly influences the amount of time that the larva
Larva
A larva 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...
e need to complete development.
Pupae
After the larval phase, the Muscina larvae pass through a pupal stage. In this stage, there are many transformations that occur, such as the formation of legs, head, and wings. Simultaneously, a protective layer builds up and forms a cocoonPupa
A pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...
, which aids in protection of the vital organs of the fly. M. assimilis is a species in this genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
that does not form a cocoon. The duration of the pupal stage also varies depending on the temperature of the surrounding environment.
Adults
After sufficient time for pupal development has elapsed, the fly will be able to break out of its hard pupa shell, and the fly’s wings begin to spread. Although completely formed in the pupa stage, the adult’s wings do not reach its full size until outside the pupa covering. Through the use of blood vessels inside the wings, the fly is able to expand to full width and length and complete its life cycleBiological life cycle
A life cycle is a period involving all different generations of a species succeeding each other through means of reproduction, whether through asexual reproduction or sexual reproduction...
.
Medical importance
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
pathogens via transfer from its feet or mouthparts
Insect mouthparts
Insects exhibit a range of mouthparts, adapted to particular modes of feeding. The earliest insects had chewing mouthparts...
. Adult female flies tend to lay eggs in decaying material such as food or dead organisms and fresh fecal material. The fecal material houses a vast number of pathogenic bacteria, viruses, protozoan and other disease-causing agents. Most of the bacteria and viruses are not introduced from the fecal material to the fly when in the egg or larva
Larva
A larva 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...
e form; rather, the transfer occurs in the transition of a young fly to adulthood. Fecal particles attach to the fly’s outer body as it emerges from the larvae. Transfer of bacteria occurs when the fly takes off and lands on an open wound or food material. Physical contact flakes the pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
off the fly's body and causes contamination
Contamination
Contamination is the presence of a minor and unwanted constituent in material, physical body, natural environment, at a workplace, etc.-Specifics:"Contamination" also has more specific meanings in science:...
. The spread of a pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
by means of a fly’s outer body, such as its feet, to the host, is referred to as mechanical transmission. It is possible to determine the identify pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
carried by identifying the species of fly. In these instances, food sanitation
Sanitation
Sanitation is the hygienic means of promoting health through prevention of human contact with the hazards of wastes. Hazards can be either physical, microbiological, biological or chemical agents of disease. Wastes that can cause health problems are human and animal feces, solid wastes, domestic...
is an important preventive measure to ensure food safety
Food safety
Food safety is a scientific discipline describing handling, preparation, and storage of food in ways that prevent foodborne illness. This includes a number of routines that should be followed to avoid potentially severe health hazards....
. Moreover, a study of flies including M. stabulans and M. assimilis has shown that fly incidence peaked about 4–5 months before the occurrence of a poliomyelitis
Poliomyelitis
Poliomyelitis, often called polio or infantile paralysis, is an acute viral infectious disease spread from person to person, primarily via the fecal-oral route...
epidemic. This time period matches the time it takes for the infective agent to incubate in a human plus the extra time necessary for the fly to acquire and incubate the virus in its body.
Forensic importance
M. stabulans and M. assimilis belong to the ecological group of the filth fly. Muscina flies are attracted to decaying organic matterOrganic matter
Organic matter is matter that has come from a once-living organism; is capable of decay, or the product of decay; or is composed of organic compounds...
, and are commonly found on corpses, urine, and feces. Muscina flies are useful in determining post-mortem intervals. The presence of Muscina larva
Larva
A larva 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...
e in diapers and on genitalia can indicate a timeline for the period of neglect in infant or elderly death cases. From the second instar
Instar
An instar is a developmental stage of arthropods, such as insects, between each molt , until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or assume a new form. Differences between instars can often be seen in altered body proportions, colors, patterns, or...
phase onwards, M. stabulans are predacious upon other larvae, and will eat other forensically important arthropods. Presence of the false stable fly larva
Larva
A larva 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...
e on buried bodies enables investigators to estimate the time of death. The antennae
Antenna (biology)
Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....
of the false stable fly can detect buried bodies. In these cases, the fly lays its eggs on top of the soil, and the hatching larvae will then burrow and invade the corpse. The false stable fly will also lay its eggs in blood
Blood
Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....
, even in the absence of a body. The presence of eggs in blood allows entomologists to estimate the time of injury, which helps investigators and crime scene investigators. Muscina stabulans are found on corpses in autumn and winter. In one experiment, M. stabulans larvae were found on a rabbit corpse two days after death. M. stabulans are present in the fresh stage, but are predominantly found in the adipocere
Adipocere
Adipocere , also known as corpse, grave or mortuary wax, is a wax-like organic substance formed by the anaerobic bacterial hydrolysis of fat in tissue, such as body fat in corpses...
-like stage, characterized by the hydrolysis
Hydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
of the carcass’ fatty tissue. In this phase, the carcass loses its shape and is a mass of hair, fat, skin, and cartilage
Cartilage
Cartilage is a flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs...
. The skin eventually becomes rigid, protecting the larva
Larva
A larva 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...
e on the carcass and the insects living underneath the carcass.
Myiasis
MyiasisMyiasis
Myiasis is a general term for infection by parasitic fly larvae feeding on the host's necrotic or living tissue. Colloquialisms for myiasis include flystrike, blowfly strike, and fly-blown. In Greek, "myia" means fly....
is the feeding on live humans and vertebrate
Vertebrate
Vertebrates are animals that are members of the subphylum Vertebrata . Vertebrates are the largest group of chordates, with currently about 58,000 species described. Vertebrates include the jawless fishes, bony fishes, sharks and rays, amphibians, reptiles, mammals, and birds...
s by dipterous
Diptera
Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
fly larvae.
Human
There have been rare instances of myiasis linked to M. stabulans. A twenty year-old male from a rural part of IndiaIndia
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
was reported with a rare case of intestinal myiasis. Symptoms included abdominal discomfort, bloated abdomen, and intestinal hurrying after meals. His stool
Feces
Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
sample was watery and contained sparse fecal matter, but it was littered with maggot
Maggot
In everyday speech the word maggot means the larva of a fly ; it is applied in particular to the larvae of Brachyceran flies, such as houseflies, cheese flies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and Crane flies...
s. A repeat sample two hours later also displayed positive signs of maggots. The maggots were washed in 0.9% normal saline
Saline (medicine)
In medicine, saline is a general term referring to a sterile solution of sodium chloride in water but is only sterile when it is to be placed intravenously, otherwise, a saline solution is a salt water solution...
solution and in distilled water and were subsequently preserved in 10% formalin before being submitted to the Vector Control Research Center (VCRC), Pondicherry, for definite species identification. Upon arrival, the maggots were rinsed again with distilled water and dropped into a solution of 10% sodium hydroxide for six hours. The last segment on the maggot was transected, and by using a Zeiss binocular dissection microscope, the spiracular plate was removed and placed in Hoyer’s medium. By attaching a camera to a MOTIC BA 300 digital compound microscope, pictures were taken of the whole larva and the spiracular plate. The maggots were approximately 6–7 mm length-wise and 1–1.5 mm in width and appeared a dullish-white in color. Their carcasses were coated with a tough integument consisting of multiple bands of minute, grayish-brown spines. Closer examination with a microscope revealed a total of 11 separate segments. Each segment, except for the anal segment, had a belt of small, well-developed spines going towards the posterior margins. The anterior and posterior regions were similarly narrow while the middle appeared broad. Two hooks were found on the pseudo-cephalic segment of the maggot
Maggot
In everyday speech the word maggot means the larva of a fly ; it is applied in particular to the larvae of Brachyceran flies, such as houseflies, cheese flies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and Crane flies...
which enabled them to attach to the mucosal lining of the intestine. The appearance of spiracular slits on the solid plate on the peritreme of the posterior spiracle
Spiracle
Spiracles are openings on the surface of some animals that usually lead to respiratory systems.-Vertebrates:The spiracle is a small hole behind each eye that opens to the mouth in some fishes. In the primitive jawless fish the first gill opening immediately behind the mouth is essentially similar...
narrowed the results down to the genus Muscina. The curve in the spiracular slit at the middle verified that the species was M. stabulans.
Muscina flies are rarely seen on the skin of living mammals, but there has been one reported case where a Muscina species alone caused cutaneous myiasis in a human. A nine-year-old girl from Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...
was reported with a lump on her wrist that was reddened and elevated, but showed no signs of any external openings or contains any pus inside. A vaseline bandage was applied after some blood was extracted, and the lump was soaked in hot water several times. Twelve hours later, a worm was found in the cut after removing the bandage. Several other small lesions were noticeable around the proximity of the cut, but they receded at about this time. The girl recovered after applying a hot pack to the lesion. The larvae were confirmed by M. T. James of the State College of Washington
Washington State University
Washington State University is a public research university based in Pullman, Washington, in the Palouse region of the Pacific Northwest. Founded in 1890, WSU is the state's original and largest land-grant university...
and C. W. Sabrosky and W. W. Wirth of the United States National Museum to be a Muscina fly, most likely M. assimilis.
Sheep
In certain parts of the world where sheep production is important, ovine myiasis by certain dipteran species is a major concern. Areas where ruminant myiasis are problematic are AustraliaAustralia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, Southern Africa
Southern Africa
Southern Africa is the southernmost region of the African continent, variably defined by geography or geopolitics. Within the region are numerous territories, including the Republic of South Africa ; nowadays, the simpler term South Africa is generally reserved for the country in English.-UN...
, and the British Isles
British Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...
. M. pabulorum along with other dipteran flies have been identified in cases in southwestern Scotland
Scotland
Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...
.
Ongoing research
Current research have delved into the role Muscina flies play in forensics. Muscina stabulans was found to be an important fly in the determination of post-mortem intervals (PMI) in the Rio Grande do Sul state in southern BrazilBrazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
. M. stabulans show up during the adipocere
Adipocere
Adipocere , also known as corpse, grave or mortuary wax, is a wax-like organic substance formed by the anaerobic bacterial hydrolysis of fat in tissue, such as body fat in corpses...
-like stage of decomposition whereby the carcass
Carrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...
loses its natural shape due to hydrolysis of the fatty tissue. Moreover, M. stabulans appearance on bodies in large numbers during the autumn and winter months is useful in narrowing down time of death.
Species
- Muscina angustifrons LoewHermann LoewFriedrich Hermann Loew was a German entomologist who specialised in the study of Diptera, an order of insects including flies, mosquitoes, gnats and midges...
, 1858 - Muscina arcuata Shinonaga, 1989
- Muscina aurantiaca Hough, 1899
- Muscina brunnea
- Muscina concolor
- Muscina dorsilinea Wulp, 1896
- Muscina flukei Snyder, 1956
- Muscina fulvacrura Snyder, 1956
- Muscina fungivora Robineau-DesvoidyJean-Baptiste Robineau-DesvoidyAndré Jean Baptiste Robineau-Desvoidy was a French physician and entomologist specialising in the study of Diptera and to some extent of the Coleoptera .-Achievements:...
, 1830 - Muscina grisea
- Muscina heterochaeta VilleneuveJoseph Th.Villeneuve de JantiJoseph Villeneuve de Janti Was a French entomologist who specialised inDiptera .He worked at the Pasteur Institute in Paris and at the Muséum national d'histoire naturelle in the same city.As well as naming many new taxa Villeneuve made many significant contributions to medical entomology.He...
, 1915 - Muscina japonica Shinonaga, 1974
- Muscina krivosheinae Lobanov, 1977
- Muscina latipennis
- Muscina levidaMuscina levidaMuscina levida is a fly from the family Muscidae....
HarrisMoses HarrisMoses Harris was an English entomologist and engraver.In the Natural System of Colours he examined the work of Isaac Newton and tried to reveal the multitude of colours which can be created from three basic ones...
, 1788 - Muscina longicornis
- Muscina minor Portschinsky, 1881
- Muscina pascuorum MeigenJohann Wilhelm MeigenJohann Wilhelm Meigen was a German entomologist famous for his pioneering work on Diptera.-Early years:Meigen was born in Solingen, the fifth of eight children of Johann Clemens Meigen and Sibylla Margaretha Bick. His parents, though not poor, were not wealthy either. The ran a small shop in...
, 1826 - Muscina principalis SchinerIgnaz Rudolph SchinerIgnaz Rudolf Schiner was an Austrian entomologist who specialised in Diptera.Schiner was born in Fronsburg , Horn in 1813 and died in Vienna on 6 July 1873. He was a ministerial secretary in ViennaHis most significant publications are...
, 1868 - Muscina prolapsaMuscina prolapsaMuscina prolapsa is a fly from the family Muscidae....
HarrisMoses HarrisMoses Harris was an English entomologist and engraver.In the Natural System of Colours he examined the work of Isaac Newton and tried to reveal the multitude of colours which can be created from three basic ones...
, 1780 - Muscina stabulansMuscina stabulansMuscina stabulans is a fly from the family Muscidae....
FallénCarl Fredrik FallénCarl Fredrik Fallén was a Swedish botanist and entomologist.Fallén taught at the Lund University. He wrote Diptera Sueciae .In 1817, Fallen discovered the Muscina stabulans species of flies....
, 1817 - Muscina sumatrensis Shinonaga & Kurahashi, 2002
- Muscina texana
- Muscina tripunctata Wulp, 1896
- Muscina varicolor