Hoverfly
Encyclopedia
Hoverflies, sometimes called flower flies or syrphid flies, make up the insect family
Syrphidae. As their common name
suggests, they are often seen hovering or nectaring at flower
s; the adults of many species
feed mainly on nectar and pollen
, while the larva
e (maggot
s) eat a wide range of foods. In some species, the larvae are saprotrophs, eating decaying plant and animal matter in the soil or in ponds and streams. In other species, the larvae are insectivore
s and prey on aphid
s, thrips, and other plant-sucking insects.
Aphids alone cause tens of millions of dollars of damage to crops worldwide every year; because of this, aphidophagous hoverflies are being recognized as important natural enemies
of pests, and potential agents for use in biological control. Some adult syrphid flies are important pollinator
s.
About 6,000 species in 200 genera
have been described. Hoverflies are common throughout the world and can be found on all continents except Antarctica. Hoverflies are harmless to most other animals despite their mimicry
of more dangerous wasp
s and bee
s, which serves to ward off predators.
, are small, elongate and slender, while others, like members of Criorhina
are large, hairy, and yellow and black. As members of Diptera
, all hoverflies have a single functional pair of wings (the hindwings are reduced to balancing organs). They are brightly colored, with spots, stripes, and bands of yellow or brown covering their bodies. Due to this coloring, they are often mistaken for wasps or bee
s; they exhibit Batesian mimicry
. Despite this, hoverflies are harmless.
With a few exceptions (e.g.), hoverflies are distinguished from other flies by a spurious vein, located parallel to the fourth longitudinal wing vein. Their bodies are densely covered by bristles, and adults feed mainly on nectar and pollen. They also hover around flowers, lending to their common name.
Unlike adults, the maggot
s of hoverflies feed on a variety of foods; some are saprotrophs, eating decaying plant or animal matter, while others are insectivores, eating aphids, thrips, and other plant-sucking insects. This is beneficial to gardens, as aphids destroy crops, and hoverfly maggots are often used in biological control. Certain species, such as Lampetia equestris or Eumerus tuberculatus, are responsible for pollination
.
An example of a well-known hoverfly maggot is the Rat-tailed maggot
, of the drone fly, Eristalis tenax. It has a breathing siphon at its rear end, giving it its name. The species lives in stagnant water, such as sewage and lagoons. The maggots also have a commercial use, and are sometimes sold for ice fishing
.
Hoverfly larvae are also known to cause Myiasis
among humans. This occurs when the maggots eat feces
, causing discomfort, pain, or itch
ing.
family found in most biome
s excluding deserts and the tundra
at extremely high latitudes, in Antarctica. Certain species are more common in certain areas than others; for example, the American hoverfly, Eupeodes americanus, is common in the Nearctic ecozone
, and the Common hoverfly, Melangyna viridiceps, is common in the Australasia ecozone
. There are about 6,000 species and 200 genera in the family.
Larvae of hoverflies are often found in stagnant water. Adults are often found near plants, their principal food source being nectar and pollen. Some species are found in more unusual locations; for example, members of the genus Volucella
can be found in bumblebee nests, while members of Microdon
are myrmecophiles, found in ant or termite nests. Others can be found in decomposing vegetation.
s and the leafhopper
s which spread some diseases like curly top
. Therefore they are seen in biocontrol as a natural means of reducing the levels of pests.
Gardeners, therefore, will sometimes use companion plants to attract hoverflies. Those reputed to do so include alyssum
, Iberis umbellata
, statice, buckwheat
, chamomile
, parsley
, and yarrow
.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Syrphidae. As their common name
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
suggests, they are often seen hovering or nectaring at flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s; the adults of many species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
feed mainly on nectar and pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
, while 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 (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) eat a wide range of foods. In some species, the larvae are saprotrophs, eating decaying plant and animal matter in the soil or in ponds and streams. In other species, the larvae are insectivore
Insectivore
An insectivore is a type of carnivore with a diet that consists chiefly of insects and similar small creatures. An alternate term is entomophage, which also refers to the human practice of eating insects....
s and prey on aphid
Aphid
Aphids, also known as plant lice and in Britain and the Commonwealth as greenflies, blackflies or whiteflies, are small sap sucking insects, and members of the superfamily Aphidoidea. Aphids are among the most destructive insect pests on cultivated plants in temperate regions...
s, thrips, and other plant-sucking insects.
Aphids alone cause tens of millions of dollars of damage to crops worldwide every year; because of this, aphidophagous hoverflies are being recognized as important natural enemies
Predation
In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...
of pests, and potential agents for use in biological control. Some adult syrphid flies are important pollinator
Pollinator
A pollinator is the biotic agent that moves pollen from the male anthers of a flower to the female stigma of a flower to accomplish fertilization or syngamy of the female gamete in the ovule of the flower by the male gamete from the pollen grain...
s.
About 6,000 species in 200 genera
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...
have been described. Hoverflies are common throughout the world and can be found on all continents except Antarctica. Hoverflies are harmless to most other animals despite their mimicry
Batesian mimicry
Batesian mimicry is a form of mimicry typified by a situation where a harmless species has evolved to imitate the warning signals of a harmful species directed at a common predator...
of more dangerous wasp
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...
s and bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s, which serves to ward off predators.
Description
The size of hoverflies varies, depending on the species. Some, like members of the genus BacchaBaccha (hoverfly)
Baccha is a genus of hoverflies in the subfamily Syrphinae. They are typically moderate sized with wasp-like markings. Their larvae are predatory, often on aphids.-Species:*Baccha apicalis *Baccha bequaerti Curran, 1929...
, are small, elongate and slender, while others, like members of Criorhina
Criorhina
Criorhina is a genus of hoverflies.-Species:*C. asilica *C. aurea Lovett, 1919*C. berberina *C. brevipila Loew, 1871*C. bubulcus *C. caudata Curran, 1925...
are large, hairy, and yellow and black. As members of 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...
, all hoverflies have a single functional pair of wings (the hindwings are reduced to balancing organs). They are brightly colored, with spots, stripes, and bands of yellow or brown covering their bodies. Due to this coloring, they are often mistaken for wasps or bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s; they exhibit Batesian mimicry
Batesian mimicry
Batesian mimicry is a form of mimicry typified by a situation where a harmless species has evolved to imitate the warning signals of a harmful species directed at a common predator...
. Despite this, hoverflies are harmless.
With a few exceptions (e.g.), hoverflies are distinguished from other flies by a spurious vein, located parallel to the fourth longitudinal wing vein. Their bodies are densely covered by bristles, and adults feed mainly on nectar and pollen. They also hover around flowers, lending to their common name.
Reproduction and life cycle
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 of hoverflies feed on a variety of foods; some are saprotrophs, eating decaying plant or animal matter, while others are insectivores, eating aphids, thrips, and other plant-sucking insects. This is beneficial to gardens, as aphids destroy crops, and hoverfly maggots are often used in biological control. Certain species, such as Lampetia equestris or Eumerus tuberculatus, are responsible for pollination
Pollination
Pollination is the process by which pollen is transferred in plants, thereby enabling fertilisation and sexual reproduction. Pollen grains transport the male gametes to where the female gamete are contained within the carpel; in gymnosperms the pollen is directly applied to the ovule itself...
.
An example of a well-known hoverfly maggot is the Rat-tailed maggot
Rat-tailed maggot
Rat-tailed maggots are the larvae of some species of hoverfly, commonly Eristalis tenax. A characteristic feature of rat-tailed maggots is a tube-like, three segmented, telescoping breathing siphon located at their posterior end. This acts like a snorkel, allowing the larva to breathe air while...
, of the drone fly, Eristalis tenax. It has a breathing siphon at its rear end, giving it its name. The species lives in stagnant water, such as sewage and lagoons. The maggots also have a commercial use, and are sometimes sold for ice fishing
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 anglers may sit on the stool in the open on a frozen lake, or in a heated cabin on the ice, some with bunks and amenities.-Locations:It is a popular pastime...
.
Hoverfly larvae are also known to cause Myiasis
Myiasis
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....
among humans. This occurs when the maggots eat feces
Feces
Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
, causing discomfort, pain, or itch
Itch
Itch is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to classify it as any one type of sensory experience. Modern science has shown that itch has many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response...
ing.
Distribution and habitat
Hoverflies are a cosmopolitanCosmopolitan distribution
In biogeography, a taxon is said to have a cosmopolitan distribution if its range extends across all or most of the world in appropriate habitats. For instance, the killer whale has a cosmopolitan distribution, extending over most of the world's oceans. Other examples include humans, the lichen...
family found in most biome
Biome
Biomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...
s excluding deserts and the tundra
Tundra
In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...
at extremely high latitudes, in Antarctica. Certain species are more common in certain areas than others; for example, the American hoverfly, Eupeodes americanus, is common in the Nearctic ecozone
Ecozone
An ecozone is the broadest biogeographic division of the Earth's land surface, based on distributional patterns of terrestrial organisms.Ecozones delineate large areas of the Earth's surface within which organisms have been evolving in relative isolation over long periods of time, separated from...
, and the Common hoverfly, Melangyna viridiceps, is common in the Australasia ecozone
Australasia ecozone
The Australasian zone is an ecological region that is coincident, but not synonymous , with the geographic region of Australasia...
. There are about 6,000 species and 200 genera in the family.
Larvae of hoverflies are often found in stagnant water. Adults are often found near plants, their principal food source being nectar and pollen. Some species are found in more unusual locations; for example, members of the genus Volucella
Volucella
Volucella is a genus of large, broad-bodied, dramatic hover-flies. They have distinctive plumose aristas and the face is extended downward. They are strongly migratory and males are often territorial. Adults feed on nectar of flowers and are often seen sunning on leaves...
can be found in bumblebee nests, while members of Microdon
Microdon
Hover flies of the genus Microdon are unusual among the Diptera. Like other members of the subfamily, they are myrmecophiles, meaning they inhabit the nests of ants...
are myrmecophiles, found in ant or termite nests. Others can be found in decomposing vegetation.
Relationship with people
Many species of hoverfly larvae prey upon pest insects, including aphidAphid
Aphids, also known as plant lice and in Britain and the Commonwealth as greenflies, blackflies or whiteflies, are small sap sucking insects, and members of the superfamily Aphidoidea. Aphids are among the most destructive insect pests on cultivated plants in temperate regions...
s and the leafhopper
Leafhopper
Leafhopper is a common name applied to any species from the family Cicadellidae. Leafhoppers, colloquially known as hoppers, are minute plant-feeding insects in the superfamily Membracoidea in the order Hemiptera...
s which spread some diseases like curly top
Curly top
Curly top is a disease, first noted in the United States in 1898, which strikes various types of plants, including tomato, chili pepper, eggplant, potatoes, and others, causing them to stop growing or producing fruit, often eventually dying...
. Therefore they are seen in biocontrol as a natural means of reducing the levels of pests.
Gardeners, therefore, will sometimes use companion plants to attract hoverflies. Those reputed to do so include alyssum
Alyssum
Alyssum is a genus of about 100–170 species of flowering plants in the family Brassicaceae, native to Europe, Asia, and northern Africa, with the highest species diversity in the Mediterranean region...
, Iberis umbellata
Iberis umbellata
Iberis umbellata, common name Candytuft or Globe Candytuft, is a herbaceous annual flowering plant of the genus Iberis and the family Brassicaceae.-Etymology:...
, statice, buckwheat
Buckwheat
Buckwheat refers to a variety of plants in the dicot family Polygonaceae: the Eurasian genus Fagopyrum, the North American genus Eriogonum, and the Northern Hemisphere genus Fallopia. Either of the latter two may be referred to as "wild buckwheat"...
, chamomile
Chamomile
Chamomile or camomile is a common name for several daisy-like plants of the family Asteraceae. These plants are best known for their ability to be made into an infusion which is commonly used to help with sleep and is often served with either honey or lemon. Because chamomile can cause uterine...
, parsley
Parsley
Parsley is a species of Petroselinum in the family Apiaceae, native to the central Mediterranean region , naturalized elsewhere in Europe, and widely cultivated as an herb, a spice and a vegetable.- Description :Garden parsley is a bright green hairless biennial herbaceous plant in temperate...
, and yarrow
Yarrow
Achillea millefolium or yarrow is a flowering plant in the family Asteraceae, native to the Northern Hemisphere. In New Mexico and southern Colorado, it is called plumajillo, or "little feather", for the shape of the leaves. In antiquity, yarrow was known as herbal militaris, for its use in...
.
Identification guides
- Stubbs, A.E. and Falk, S.J. (2002) British Hoverflies An Illustrated Identification Guide. Pub. 1983 with 469 pages, 12 col plates, b/w illus.British Entomological and Natural History Society [ISBN 1-899935-05-3]. 276 species are described with extensive keys to aid identification. 190 species are displayed on the colour plates. 2nd edition, pub. 2002, includes new British species and name changes. Also includes European species which are likely to be found in Britain. There are additional black & white plates illustrating the male genitalia of the difficult genera Cheilosia and Sphaerophoria.
- Vockeroth , J.R. A revision of the genera of the Syrphini (Diptera: Syrphidae) Memoirs of the Entomological Society of Canada, no. 62:1-176. Keys subfamilies, tribesTribe (biology)In biology, a tribe is a taxonomic rank between family and genus. It is sometimes subdivided into subtribes.Some examples include the tribes: Canini, Acalypheae, Hominini, Bombini, and Antidesmeae.-See also:* Biological classification* Rank...
and genera on a world basis and under regions. - van Veen, M.P. |(2004) "Hoverflies of Northwest Europe, Identification Keys to the Syrphidae". KNNV Publishing, Utrecht. [ISBN 9050111998]
See also
- Episyrphus balteatusEpisyrphus balteatusEpisyrphus balteatus, sometimes called the marmalade hoverfly , is a relatively small hoverfly of the Syrphidae family, widespread throughout all continents. Like most other hoverflies it mimics a much more dangerous insect, the solitary wasp, though it is a quite harmless species. The upper...
- marmalade fly (worldwide distribution) - List of hoverfly species of Great Britain
- List of New Zealand Flower Flies
- List of the Flower Flies of North America
External links
- Hoverfly - index to scholarly articles
- A web-site about Dutch hoverflies
- All About Hoverflies
- Hoverfly Recording Scheme - UK Dipterists Forum
- Syrphidae species in Europe, with photos, range maps and literature
- Large numbers of Syrphidae photos
- Northwest Europe Hoverflies - archived at The Wayback Machine
- Photographs of World Hoverflies from Japan, in English
- Diptera.info Picture Gallery