''Hydrotaea'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of insects in the housefly family,

Muscidae Muscidae are a family of flies found in the superfamily Muscoidea. Muscidae, some of which are commonly known as house flies or stable flies due to their synanthropy, are worldwide in distribution and contain almost 4,000 described species i ...

. They occur in most regions of the world but are more populous in warmer climates. They are often found on

feces Feces (also known as faeces American and British English spelling differences#ae and oe, or fæces; : faex) 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 ...

in summer months, and are therefore generally found in close proximity to

livestock Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The t ...

. Among the 130 known species in this genus, one of the most commonly recognized is the dump fly. Along with many other genera in the family, ''Hydrotaea'' is of

forensic Forensic science combines principles of law and science to investigate criminal activity. Through crime scene investigations and laboratory analysis, forensic scientists are able to link suspects to evidence. An example is determining the time and ...

importance in both the economic and public health scene. Flies in general are considered by many authorities to be the most important insects involved in

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

and

veterinary medicine Veterinary medicine is the branch of medicine that deals with the prevention, management, medical diagnosis, diagnosis, and treatment of disease, disorder, and injury in non-human animals. The scope of veterinary medicine is wide, covering all a ...

. Certain ''Hydrotaea'' species have been proven to carry and transmit certain diseases to warm blooded animals, including humans. Researchers continue to monitor these vectors of disease as they have been connected with the spread of

mastitis Mastitis is inflammation of the breast or udder, usually associated with breastfeeding. Symptoms typically include local pain and redness. There is often an associated fever and general soreness. Onset is typically fairly rapid and usually occ ...

Species

Description

Larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e of this genus are often dimorphic obligate

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they ar ...

s. The second and third

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

s are predators, and the first is also carnivorous in some species. Some species have

cannibalistic Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is also well documente ...

final instars. The smallest larvae are under 6 mm and the largest are up to 16 mm. The abdomen has ventral welts and large spiracles with sinuate slits. Adults commonly feed on the

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is com ...

mammal A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...

s. They are able to reopen wounds that are almost completely healed. Mouthpart

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

in the genus ranges from sponging mouthparts to mouths with rasping teeth. Many species have enlarged prestomal teeth. The metathoracic spiracle is covered in long, thick

seta In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae, ...

e. The average male ''Hydrotaea'' is 6.5–8.5 mm and the average female is 5.75–7.5 mm. They are very light brown to bluish black with large, red eyes and plumose antennae.

Habitat

Flies in this genus are found in the warmer parts of

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating Direction (geometry), direction or geography. Etymology T ...

and

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

, and

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

. They are most commonly found in

urban Urban means "related to a city". In that sense, the term may refer to: * Urban area, geographical area distinct from rural areas * Urban culture, the culture of towns and cities Urban may also refer to: General * Urban (name), a list of people ...

settings. They are attracted to

fermentation Fermentation is a type of anaerobic metabolism which harnesses the redox potential of the reactants to make adenosine triphosphate (ATP) and organic end products. Organic molecules, such as glucose or other sugars, are catabolized and reduce ...

and are often found in

vegetation Vegetation is an assemblage of plants and the ground cover they provide. It is a general term, without specific reference to particular Taxon, taxa, life forms, structure, Spatial ecology, spatial extent, or any other specific Botany, botanic ...

, and decomposing carcasses, mainly those dead longer than ten days.

Life cycle

The life cycle of ''Hydrotaea rostrata'' has been studied in the field of

forensic entomology Forensic entomology is a branch of applied entomology that uses insects and other arthropods as a basis for legal evidence. Insects may be found on cadavers or elsewhere around crime scenes in the interest of forensic science. Forensic entom ...

. Mature flies seek out decay, preferably in material that has been dead for an extended amount of time. Masses of

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, hoverflies, and blowflies, rather than larvae of the Nematocera, such as mosquitoes and cr ...

s, which are often characteristic of other species of flies, are not typical of ''H. rostrata''. The larvae of this species progress through three stages, or

s, which are then followed by the formation of a

pupa A pupa (; : 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 life cycle, the stages th ...

. The adult fly emerges from the pupa. The developmental process from egg to adult takes between 518.4 and 1555.6 hours, according to one study in Australia. Development is more rapid in warmer temperatures of . In cooler temperatures of , development may take up to 64.5 days. The larvae of another species, the black dump fly (''H. aenescens''), inhabit fecal material and consume other larvae, including those of '' Musca domestica'', the housefly. The black dump fly is commercially available for use in housefly control. It is also useful in forensics, as it may inhabit

corpses A cadaver, often known as a corpse, is a dead human body. Cadavers are used by medical students, physicians and other scientists to study anatomy, identify disease sites, determine causes of death, and provide tissue to repair a defect in a liv ...

. Some larvae are able to seek shelter underground in cold conditions.

Associated pathogens

Research has incriminated ''Hydrotaea irritans'' as a vector of summer

, a

bovine Bovines (subfamily Bovinae) comprise a diverse group of 10 genera of medium to large-sized ungulates, including Bos, cattle, bison, African buffalo, Bubalus, water buffalos, and the four-horned and spiral-horned antelopes. The members of this gro ...

infection that can be caused by multiple suspected

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

. The research allowed flies inoculated with select bacteria from a sample representing summer mastitis to come in contact with the

udder An udder is an organ formed of two or four mammary glands on the females of dairy animals and ruminants such as cattle, goats, and sheep. An udder is equivalent to the breast in primates, elephantine pachyderms and other mammals. The udder is ...

s of

cattle Cattle (''Bos taurus'') are large, domesticated, bovid ungulates widely kept as livestock. They are prominent modern members of the subfamily Bovinae and the most widespread species of the genus '' Bos''. Mature female cattle are calle ...

. The bacteria appeared in some of the cows and on the bodies of just over a third of the doctored flies. The evidence indicates that ''H. irritans'' transmits the bacterial species ''

Staphylococcus aureus ''Staphylococcus aureus'' is a Gram-positive spherically shaped bacterium, a member of the Bacillota, and is a usual member of the microbiota of the body, frequently found in the upper respiratory tract and on the skin. It is often posi ...

'', ''

Streptococcus dysgalactiae ''Streptococcus dysgalactiae'' is a gram positive, beta-haemolytic, coccal bacterium belonging to the family ''Streptococcaceae''. It is capable of infecting both humans and animals, but is most frequently encountered as a commensal of the alim ...

'', '' Streptococcus uberis'', ''

Streptococcus agalactiae ''Streptococcus agalactiae'' (also known as group B streptococcus or GBS) is a gram-positive coccus (round bacterium) with a tendency to form chains (as reflected by the genus name ''Streptococcus''). It is a beta-hemolytic, catalase-negative, an ...

'', '' Arcanobacterium pyogenes'', '' Peptostreptococcus indolicus'', and '' Fusobacterium necrophorum''. ''H. irritans'' attacks many other warm-blooded animals, including humans. ''H. aenescens'' also carries bacteria, particularly ''Salmonella'' serovar Infantis.

Forensic importance

''Hydrotaea'' species have been helpful in forensic cases worldwide by indicating

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 ...

(PMI). These flies typically inhabit a carcass 4 to 5 months after the start of

decomposition Decomposition is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is ess ...

. Their presence indicates that the corpse was not burned and that the earlier

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

phase has ended. ''Hydrotaea'' larvae may feed on each other and on other flies, such as blow-flies. ''Hydrotaea'' can be used to identify

drug A drug is any chemical substance other than a nutrient or an essential dietary ingredient, which, when administered to a living organism, produces a biological effect. Consumption of drugs can be via insufflation (medicine), inhalation, drug i ...

s and to determining whether a body was relocated. ''Hydrotaea spinigera'' can make up 70% of the muscid fly population on a corpse in forested habitat. ''Hydrotaea rostrata'' may arrive at a decomposing body on the second day of decay, and may stay up to 34 days or until the body is

skeleton A skeleton is the structural frame that supports the body of most animals. There are several types of skeletons, including the exoskeleton, which is a rigid outer shell that holds up an organism's shape; the endoskeleton, a rigid internal fra ...

ized.

References

{{Taxonbar, from=Q4194465 Muscidae genera Forensic entomology Diptera of North America Muscomorph flies of Europe Taxa named by Jean-Baptiste Robineau-Desvoidy Muscidae