Cecidomyiidae is a family of

flies Flies are insects of the Order (biology), order Diptera, the name being derived from the Ancient Greek, Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwin ...

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

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

tissue, creating abnormal plant growths called

gall Galls (from the Latin , 'oak-apple') or ''cecidia'' (from the Greek , anything gushing out) are a kind of swelling growth on the external tissues of plants. Plant galls are abnormal outgrowths of plant tissues, similar to benign tumors or war ...

s. 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 Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Diptera 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 advance ...

, and have long antennae. Some Cecidomyiids are also known for the strange phenomenon of

paedogenesis Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological, or somatic, development of an organism, typically an animal. Neoteny in modern humans is more signif ...

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 A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

and 830

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

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

DNA metabarcoding Metabarcoding is the DNA barcoding, barcoding of DNA/RNA (or Environmental DNA, eDNA/Environmental DNA, eRNA) in a manner that allows for the simultaneous identification of many taxa within the same sample. The main difference between barcodin ...

study published in 2016 estimated the fauna of

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

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 similar metabarcoding study performed in Costa Rica also found Cecidomyiidae to be the most diverse family of flies, supporting this assertion. A third metabarcoding study in 2023 concluded that Cecidomyiidae are the single most diverse family collected from malaise traps all around the world and are a dominant component of insect diversity, comprising about 20% of all species collected. 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 Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

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

Ocelli A simple eye or ocellus (sometimes called a pigment pit) is a form of eye or an optical arrangement which has a single lens without the sort of elaborate retina that occurs in most vertebrates. These eyes are called "simple" to distinguish the ...

are present only in the Lestremiinae. The wings are usually clear, rarely patterned. The wing bears

microtrichia Insect morphology is the study and description of the morphology (biology), physical form of insects. The terminology used to describe insects is similar to that used for other arthropods due to their shared evolutionary history. Three physical f ...

, often as scales, and some species have macrotrichia. The number of longitudinal veins is reduced. Only

veins Veins () are blood vessels in the circulatory system of humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are those of the pulmonary and fetal c ...

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. Gall midge larvae, and many adults, are orange or yellow in color due to

carotenoid Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, cana ...

s. Cecidomyiidae are among the very few animals which can synthesize carotenoids, but its unknown to what degree ''de novo'' biosynthesis of carotenoids accounts for their characteristic color as opposed to dietary sequestration or endosymbionts. The genes responsible for carotenoid synthesis likely originate from

horizontal gene transfer Horizontal gene transfer (HGT) or lateral gene transfer (LGT) is the movement of genetic material between organisms other than by the ("vertical") transmission of DNA from parent to offspring (reproduction). HGT is an important factor in the e ...

from a fungal donor. 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 (''Mayetiola destructor''), or barley midge, 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 in ...

, a wheat pest, as the galls cause severe damage. Other important pests of this family are the wheat blossom midge '' Sitodiplosis mosellana'', 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 ''Orseolia oryzivora'', also called the African rice gall midge, is a species of small fly in the family Cecidomyiidae. It is a major insect pest of rice Rice is a cereal grain and in its Domestication, domesticated form is the staple ...

'') attack grain crops such as

pearl millet Pearl millet (''Cenchrus americanus'', commonly known as the synonym ''Pennisetum glaucum'') is the most widely grown type of millet. It has been grown in Africa and the Indian subcontinent since prehistoric times. The center of diversity, and ...

Mali Mali, officially the Republic of Mali, is a landlocked country in West Africa. It is the List of African countries by area, eighth-largest country in Africa, with an area of over . The country is bordered to the north by Algeria, to the east b ...

and other countries of the

Sahel The Sahel region (; ), or Sahelian acacia savanna, is a Biogeography, biogeographical region in Africa. It is the Ecotone, transition zone between the more humid Sudanian savannas to its south and the drier Sahara to the north. The Sahel has a ...

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 (''Vicia lens'' or ''Lens culinaris'') is an annual plant, annual legume grown for its Lens (geometry), lens-shaped edible seeds or ''pulses'', also called ''lentils''. It is about tall, and the seeds grow in Legume, pods, usually w ...

flower midge (''

Contarinia lentis ''Contarinia'' is a genus of midges, small flies in the family Cecidomyiidae. There are over 300 described species in the genus. Description As cecidomyiids, adult ''Contarinia'' are flies with hairy wings and long antennae. Males have antenn ...

''), the

lucerne Lucerne ( ) or Luzern ()Other languages: ; ; ; . is a city in central Switzerland, in the Languages of Switzerland, German-speaking portion of the country. Lucerne is the capital of the canton of Lucerne and part of the Lucerne (district), di ...

flower midge ('' C. medicaginis''), and the

alfalfa Alfalfa () (''Medicago sativa''), also called lucerne, is a perennial plant, perennial flowering plant in the legume family Fabaceae. It is cultivated as an important forage crop in many countries around the world. It is used for grazing, hay, ...

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 ''Dasineura brassicae'', the brassica pod midge, is a rapeseed Rapeseed (''Brassica napus'' subsp. ''napus''), also known as rape and oilseed rape and canola, is a bright-yellow flowering member of the family Brassicaceae (mustard or cabbag ...

'') on the

Cruciferae Brassicaceae () or (the older but equally valid) 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 a ...

; the

pear Pears are fruits produced and consumed around the world, growing on a tree and harvested in late summer into mid-autumn. The pear tree and shrub are a species of genus ''Pyrus'' , in the Family (biology), family Rosaceae, bearing the Pome, po ...

midge (''

Contarinia pyrivora ''Contarinia'' is a genus of midges, small flies in the family Cecidomyiidae. There are over 300 described species in the genus. Description As cecidomyiids, adult ''Contarinia'' are flies with hairy wings and long antennae. Males have antenn ...

'') and the

raspberry The raspberry is the edible fruit of several plant species in the genus ''Rubus'' of the Rosaceae, rose family, most of which are in the subgenus ''Rubus#Modern classification, Idaeobatus''. The name also applies to these plants themselves. Ras ...

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

Rhopalomyia solidaginis ''Rhopalomyia solidaginis'', the goldenrod bunch gall, is a species of gall midges, insects in the family Cecidomyiidae. The galls of this species have the following host species of goldenrods: ''Solidago altissima'', ''Solidago canadensis'', an ...

'') 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 genu ...

stalks, Porricondylini spp. on ''Citrus'', '' Lestremia'' 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 In South Africa, ''Dasineura rubiformis'' has been deployed against the invasive Australian ''

Acacia mearnsii ''Acacia mearnsii'', commonly known as black wattle, late black wattle or green wattle, is a species of flowering plant in the family Fabaceae and is Endemism, endemic to south-eastern Australia. It is usually an erect tree with smooth bark, Glo ...

''; it oviposits eggs into the flowers which develop into galls, thus reducing seed production.Impson, F. A. C., Kleinjan, C. A., Hoffmann, J. H., & Post, J. A. (2008). ''Dasineura rubiformis'' (Diptera: Cecidomyiidae), a new biological control agent for ''Acacia mearnsii'' in South Africa. South African Journal of Science, 104(7-8), 247-249. Parasitoids hosted by Cecidomyiidae include

Braconidae The Braconidae are a family of parasitoid wasps. After the closely related Ichneumonidae, braconids make up the second-largest family in the order Hymenoptera, with about 17,000 recognized species and many thousands more undescribed. One analysis ...

(Opiinae, Euphorinae),

Eurytomidae The Eurytomidae are a family within the superfamily Chalcidoidea. Unlike most chalcidoids, the larvae of many are phytophagous (feeding in stems, seeds, or galls), while others are more typical parasitoids, though even then the hosts are usuall ...

Eulophidae The Eulophidae is a large family of hymenopteran insects, with over 4,300 described species in some 300 genera. The family includes the genus '' Elasmus'', which used to be treated as a separate family, "Elasmidae", and is now treated as a subfa ...

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 The Pteromalidae are a large family of wasps, the majority being parasitoids of other insects. They are found throughout the world in virtually all habitats, and many are important as biological control agents. The oldest known fossil is known fr ...

Eupelmidae Eupelmidae is a family of parasitic wasps in the superfamily Chalcidoidea. The larvae of the majority are primary parasitoids, commonly on beetle larvae, though many other hosts are attacked, including spiders. Details of the life history varies ...

Trichogrammatidae The Trichogrammatidae are a family of small endoparasitoid wasps in the superfamily Chalcidoidea that include some of the smallest of all insects, with most species having adults less than 1 mm in length, with species of '' Megaphragma'' ...

, and

Aphelinidae The Aphelinidae are a moderate-sized family of tiny parasitic wasps, with about 1100 described species in some 28 genera. These minute insects are challenging to study, as they deteriorate rapidly after death unless extreme care is taken (e.g., ...

. 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 in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

y, and some are reported as

parasitic Parasitism is a close relationship between species, where one organism, the parasite, lives (at least some of the time) on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The ent ...

. The most common prey are

aphids Aphids are small sap-sucking insects in the Taxonomic rank, family Aphididae. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white Eriosomatinae, woolly ...

and

spider mites Spider mites are members of the family Tetranychidae, which includes about 1,200 species. They are part of the subclass Acari (mites). Spider mites generally live on the undersides of leaves of plants, where they may spin protective silk webs, a ...

, followed by

scale insect Scale insects are small insects of the Order (biology), order Hemiptera, suborder Sternorrhyncha. Of dramatically variable appearance and extreme sexual dimorphism, they comprise the infraorder Coccomorpha which is considered a more convenient g ...

s, then other small prey such as

whiteflies Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The A ...

and

thrips Thrips (Order (biology) , order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Entomologists have species description , described approximately 7,700 species. They fly on ...

, 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 ''Aphidoletes aphidimyza'', commonly referred to as the aphid midge, is a midge whose larvae feed on over 80 aphid species, including the green peach aphid. Description The adults are small (less than long), black, delicate flies (similar ...

'', is an important component of biological control programs for greenhouse crops and is widely sold in the United States.

References

External links

Diptera.info images

at delta-intkey.com {{Authority control Cecidomyiidae, 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