Cecidomyiidae is a family of

flies Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced m ...

known as gall midges or gall gnats. As the name implies, the

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. ...

e of most gall midges feed within

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclu ...

tissue, creating abnormal plant growths called galls. Cecidomyiidae are very fragile small insects usually only in length; many are less than long. They are characterised by hairy wings, unusual in the order Diptera, and have long antennae. Some Cecidomyiids are also known for the strange phenomenon of paedogenesis in which the larval stage reproduces without maturing first. In some species, the daughter larvae consume the mother, while in others, reproduction occurs later on in the egg or pupa. More than 6,650

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

and 830 genera are described worldwide, though this is certainly an underestimate of the actual diversity of this family. A

DNA barcoding DNA barcoding is a method of species identification using a short section of DNA from a specific gene or genes. The premise of DNA barcoding is that by comparison with a reference library of such DNA sections (also called " sequences"), an indi ...

study published in 2016 estimated the fauna of

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

alone to be in excess of 16,000 species, hinting at a staggering global count of over 1 million cecidomyiid species that have yet to be described, which would make it the most speciose single family in the entire animal kingdom. A second study performed in Costa Rica also found Cecidomyiidae to be the most diverse family of flies, supporting this assertion. WillistonCecidomyiidae

Description

Cecidomyiidae are minute to small (0.5–3.0 mm), rarely larger (up to 8 mm, wing length 15 mm) flies with a delicate appearance. Except for a few genera with reduced wings, the eyes are

holoptic Holoptic refers to one of the ways in which the arthropod eye develops, particularly the eyes of various species of insects. Unlike dichoptic and cycloptic eyes, holoptic eyes meet along the median dorsal line of the head, in many species near ...

. The mouthparts are reduced. Cecidomyiid antennae are notably long, with 12–14 segments, (sometimes fewer and up to 40 in some genera). The antennal segments either consist of a basal thickening and petiole or they are binodal, with a proximal node, an intermediate petiole and a distal node. Basal, medial, and apical whorls of hairs occur on the antennal segments. In some species, whorls of loop-shaped sensory filaments are also found, the basal or medial one sometimes being reduced. Some gall flies have only one (basal) whorl of hairs on the antennal segments, and the sensoria (transparent sensory appendages) differ in size and shape. The filaments are thread-like in the

Porricondylinae Porricondylinae is a subfamily of gall midges and wood midges in the family Cecidomyiidae. Genera List of genera, after Gagné & Jaschhof (2014):R. J. Gagné and M. Jaschhof. 201. ''A Catalog of the Cecidomyiidae (Diptera) of the World. 3rd ...

and in all the Cecidomyiinae and take the form of long loops in the supertribe Cecidomyiidi).

Ocelli A simple eye (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-l ...

are present only in the

Lestremiinae Lestremiinae is a subfamily of Cecidomyiidae Cecidomyiidae is a family of flies known as gall midges or gall gnats. As the name implies, the larvae of most gall midges feed within plant tissue, creating abnormal plant growths called galls. ...

. The wings are usually clear, rarely patterned. The wing bears microtrichia, often as scales, and some species have macrotrichia. The number of longitudinal veins is reduced. Only veins R1, R4+5, M3+4 and Cu1 are well developed in most species. The medial veins M1 and M2 are developed only in primitive groups, and the costa usually has a break just beyond vein R5. The legs are long and slender, without apical bristles. File:Catochini wing veins.svg , Catochini wing veins File:Cecidomyiinae wing veins.svg , Cecidomyiinae wing veins File:Lasiopterini wing veins.svg , Lasiopterini wing veins File:Lestremiini wing veins.svg , Lestremiini wing veins File:Micromyini and Peromyiini wing veins.svg , Micromyini and Peromyiini wing veins File:Porricondylinae (most) wing veins.svg , Porricondylinae (most) wing veins File:Winnertziini wing veins.svg , Winnertziini wing veins The genitalia of males consist of gonocoxites, gonostyles, aedeagus, and tergites 9 and 10. Lower (in the evolutionary sense) gall flies often have sclerotized parameres and a more or less transparent plate (the tegmen) located above theaedeagus-the tegmen. In higher gall flies, the parameres and tegmen are not developed. In these, instead, close to the aedeagus, is a triangular basal outgrowth of the gonocoxites called the gonosterna. Supporting structures called apodema are located near the base of the genitalia in males; these are often equipped with two outgrowths. The ovipositor is short, lamelliform, or long, mobile, and in some species, acicular. The larva is peripneustic. The head is tiny, cone-shaped, and has two posterolateral extensions. The mouthparts are reduced, with minute styliform mandibles. The relatively prominent antennae are two-segmented. Integumental setae or papillae are important in taxonomy since they are constant in number within groups. The prothorax has sclerotized sternal spatula (most). The anus is terminal in the Lestremiinae and paedogenetic in the Porricondylinae and ventral in other groups. The pupa is exarate (in a few species it is enclosed within the last instar larval integument). The anterior spiracle and anterior angle of antennal bases is prominent (most). Asphondylia solidaginis pupa gall

As a pest or biological control

Many species are economically significant, especially the

Hessian fly The Hessian fly or barley midge, ''Mayetiola destructor'', is a species of fly that is a significant pest of cereal crops including wheat, barley and rye. Though a native of Asia, upon its discovery it was believed to have been transported into N ...

, a wheat pest, as the galls cause severe damage. Other important pests of this family are the wheat blossom midge ''

Sitodiplosis mosellana ''Sitodiplosis mosellana'', the wheat midge or orange wheat blossom midge, is a species of fly in the family Cecidomyiidae. It is found in the Holarctic, where it is a significant pest of wheat, triticale and rye.Fauna Europaea References Ext ...

'', the Asian rice gall midge (''Orseolia oryzae'') and the African rice gall midge ''O. oryzivora''. The millet grain midge ('' Geromyia penniseti''), sorghum midge ('' Contarinia sorghicola''), and African rice gall midge ('' Orseolia oryzivora'') attack grain crops such as pearl millet in

Mali Mali (; ), officially the Republic of Mali,, , ff, 𞤈𞤫𞤲𞥆𞤣𞤢𞥄𞤲𞤣𞤭 𞤃𞤢𞥄𞤤𞤭, Renndaandi Maali, italics=no, ar, جمهورية مالي, Jumhūriyyāt Mālī is a landlocked country in West Africa. Mal ...

and other countries of the Sahel in West Africa. Other pests are the coffee flower midge (''Dasyneura coffeae''), Soybean pod gall midge, (''Asphondylia yushimai'') pine needle gall midge (''Thecodiplosis japonensis''), the

lentil The lentil (''Lens culinaris'' or ''Lens esculenta'') is an edible legume. It is an annual plant known for its lens-shaped seeds. It is about tall, and the seeds grow in pods, usually with two seeds in each. As a food crop, the largest pro ...

flower midge ('' Contarinia lentis''), the lucerne flower midge ('' C. medicaginis''), and the alfalfa sprout midge ('' Dasineura ignorata'') on the Leguminosae; the black locust tree gall midge (''Obolodiplosis robiniae''), the swede midge ('' Contarinia nasturtii''), and the brassica pod midge ('' Dasineura brassicae'') on the

Cruciferae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The leav ...

; the

pear Pears are fruits produced and consumed around the world, growing on a tree and harvested in the Northern Hemisphere in late summer into October. The pear tree and shrub are a species of genus ''Pyrus'' , in the family Rosaceae, bearing the po ...

midge ('' Contarinia pyrivora'') and the raspberry cane midge ('' Resseliella theobaldi'') on fruit crops; '' Horidiplosis ficifolii'' on ornamental figs, and the rosette gall midge ('' Rhopalomyia solidaginis'') on

goldenrod Goldenrod is a common name for many species of flowering plants in the sunflower family, Asteraceae, commonly in reference to the genus '' Solidago''. Several genera, such as '' Euthamia'', were formerly included in a broader concept of the gen ...

stalks, Porricondylini spp. on ''Citrus'', ''

Lestremia ''Lestremia'' is a genus of midges in the family Cecidomyiidae. There are 18 described species in this genus. It was established by French entomologist Pierre-Justin-Marie Macquart Pierre-Justin-Marie Macquart (8 April 1778 – 25 November ...

'' spp. on sweet potato, yam, ginger, garlic, onions, taro tubers, and potato, '' Lestodiplosis'' spp., '' Acaroletes'' spp., and ''Aphidoletes'' spp. on oranges, and '' Arthrocnodax'' spp. on limes.Dennis S Hill 1987 ''Agricultural Insect Pests of tropics and their control'' Cambridge. University Press , New York Parasitoids hosted by Cecidomyiidae include Braconidae (Opiinae, Euphorinae), Eurytomidae, Eulophidae,

Torymidae Torymidae is a family of wasps in the superfamily Chalcidoidea. Most species in this family are small with attractive metallic coloration, and females generally have long ovipositors. Many are parasitoids on gall-forming insects, and some are phy ...

, Pteromalidae,

Eupelmidae Eupelmidae is a family of parasitic wasps in the superfamily Chalcidoidea. The group is apparently polyphyletic, though the different subfamilies may each be monophyletic, and may be elevated to family status in the near future. As presently defi ...

, Trichogrammatidae, and Aphelinidae. All contain species which are actual or potential biological agents. A large number of gall midge species are natural enemies of other crop pests. Their larvae are

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

y, and some are reported as

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson ha ...

. The most common prey are

aphids Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A t ...

and spider mites, followed by scale insects, then other small prey such as whiteflies and

thrips Thrips (order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are ...

, which eat the eggs of other insects or mites. As the

e are incapable of moving considerable distances, a substantial population of prey must be present before the adults lay eggs, and the Cecidiomyiidae are most frequently seen during pest outbreaks. One species, '' Aphidoletes aphidimyza'', is an important component of

biological control Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also i ...

programs for greenhouse crops and is widely sold in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

. In South Africa, ''Dasineura rubiformis'' has been deployed against invasive Australian '' Acacia'' species.

References

External links

Diptera.info images

at delta-intkey.com {{Taxonbar, from=Q768519 Nematocera families Gall-inducing insects Taxa named by Edward Newman Articles containing video clips Taxa described in 1835

Description

As a pest or biological control

References

Further reading

Economic

Taxonomy

External links