Rat-tailed maggots are the

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 certain species of

hoverflies Hoverflies, also called flower flies or syrphids, make up the insect family (biology), family Syrphidae. As their common name suggests, they are often seen Hover (behaviour), hovering or nectaring at flowers; the adults of many species feed main ...

belonging to the

tribes The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

Eristalini and Sericomyiini. A characteristic feature of rat-tailed

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 is a tube-like, telescoping breathing siphon located at their posterior end. This acts like a snorkel, allowing the larva to breathe air while submerged. The siphon is usually about as long as the maggot's body ( when mature), but can be extended up to about . This organ gives the larva its common name. The most commonly encountered rat-tailed maggot is the larva of the drone fly, ''

Eristalis tenax ''Eristalis tenax'', the common drone fly, is a common, migratory, Cosmopolitan species, cosmopolitan species of hover fly. It is the most widely distributed syrphid species in the world, and is known from all regions except the Antarctic. It has ...

''. It lives in stagnant,

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

-deprived water, with a high organic content. It is fairly tolerant of

pollution Pollution is the introduction of contaminants into the natural environment that cause harm. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the component ...

and can live in

sewage Sewage (or domestic sewage, domestic wastewater, municipal wastewater) is a type of wastewater that is produced by a community of people. It is typically transported through a sewerage, sewer system. Sewage consists of wastewater discharged fro ...

lagoons and

cesspool Cesspit, cesspool and soak pit in some contexts are terms with various meanings: they are used to describe either an underground holding tank (sealed at the bottom) or a soak pit (not sealed at the bottom). A cesspit can be used for the tempo ...

Commercial use

These larvae, commonly called "mousies", are cultured and sold as fish bait. They are especially popular in

ice fishing Ice fishing is the practice of catching fish with lines and fish hooks or spears through an opening in the ice on a frozen body of water. Ice fishers may fish in the open or in heated enclosures, some with bunks and amenities. Shelters L ...

Infection

Occasionally, cases have been documented of human intestinal

myiasis Myiasis ( ), also known as flystrike or fly strike, is the parasitic infestation of the body of a live animal by fly larvae (maggots) that grow inside the host while feeding on its Biological tissue, tissue. Although flies are most commonly attr ...

caused by the rat-tailed maggot. Symptoms can range from none (

asymptomatic Asymptomatic (or clinically silent) is an adjective categorising the medical conditions (i.e., injuries or diseases) that patients carry but without experiencing their symptoms, despite an explicit diagnosis (e.g., a positive medical test). P ...

) to abdominal pain,

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 d ...

and

vomiting Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pre ...

, or

pruritus ani Pruritus ani is the irritation of the skin at the exit of the rectum, known as the anus, causing the desire to scratch. The intensity of anal itching increases from moisture, pressure, and rubbing caused by clothing and sitting. At worst, anal it ...

Infection An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...

can be caused by ingestion of contaminated food or water, but doubts have been expressed that accidentally ingested fly larvae could survive in the

gastrointestinal tract The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the Digestion, digestive system that leads from the mouth to the anus. The tract is the largest of the body's systems, after the cardiovascula ...

Zumpt Zumpt is a surname. Notable people with the surname include: * Karl Gottlob Zumpt (1792–1894), German classical scholar * August Wilhelm Zumpt (1815–1887), German classical scholar, nephew of Karl * Fritz Konrad Ernst Zumpt Fritz Konrad Er ...

proposed an alternative called "rectal myiasis". Flies, attracted to

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 ...

, may deposit their eggs or larvae near or into the

anus In mammals, invertebrates and most fish, the anus (: anuses or ani; from Latin, 'ring' or 'circle') is the external body orifice at the ''exit'' end of the digestive tract (bowel), i.e. the opposite end from the mouth. Its function is to facil ...

, and the larvae then penetrate further into the rectum. They can survive feeding on feces at this site, as long as the breathing tube reaches towards the anus.

Gallery

References

External links

{{Commons category, Rat-tailed maggots
Rat-tailed maggot
on the UF / IFAS Featured Creatures Web site Hoverflies Aquatic insects Insect common names