Chloropidae
Guides
Malloewia abdominalis
Malloewia abdominalis is a species of frit fly in the family Chloropidae, a group of small flies commonly known as grass flies or frit flies. The species was described by Becker in 1912. Chloropidae are generally associated with grasses and sedges, with larvae typically feeding on stems or roots.
Meromyza
grass flies, frit flies
Meromyza is a genus of grass flies (Diptera: Chloropidae) distributed across the Palaearctic, Nearctic, and parts of Asia including China and Mongolia. Species within this genus are primarily associated with grasses (Poaceae), with many developing on wild grass species and several recognized as pests of cereal crops including wheat, barley, and oats. The genus exhibits varying degrees of host plant specialization, from oligophagous species with broad grass host ranges to monophagous specialists. Larvae are stem-borers that feed internally on host plant tissues, with some species causing economically significant damage to small grains.
Meromyza americana
Wheat Stem Maggot
Meromyza americana, commonly known as the Wheat Stem Maggot, is a chloropid fly species whose larvae are significant pests of small grain cereals. The species completes a second generation in spring, with adults emerging to lay eggs on barley, oats, rye, wheat, and other grass hosts. Larval feeding occurs within stems, causing characteristic whitehead symptoms in infested tillers. Despite its pest status, infestations rarely exceed 1% of tillers, making insecticide treatments generally unnecessary.
Microcercis insularis
Microcercis insularis is a species of frit fly in the family Chloropidae, first described by Malloch in 1914. It belongs to the subfamily Oscinellinae and tribe Oscinellini. As with other members of Chloropidae, this species is likely associated with grassland or agricultural habitats, though specific ecological details remain poorly documented. The genus Microcercis is part of a diverse group of small flies commonly known as frit flies or grass flies.
Microcercis johanni
Microcercis johanni is a species of frit fly in the family Chloropidae, described by Foster in 2024. The genus Microcercis belongs to the tribe Oscinellini, a group of small dipterans commonly associated with grasses and sedges. As a recently described species, detailed biological information remains limited. The species epithet honors an individual named Johann.
Monochaetoscinella
Monochaetoscinella is a genus of small flies in the family Chloropidae, established by Duda in 1930. As a member of the subfamily Oscinellinae, it belongs to a group of grass flies that are generally poorly studied. The genus is distinguished by specific chaetotaxy (bristle arrangement) features, particularly the reduction in dorsocentral bristles. Species-level taxonomy and biology remain largely undocumented in accessible literature.
Neodiplotoxa
Neodiplotoxa is a genus of small flies in the family Chloropidae, established by Malloch in 1914. The genus contains four described species distributed in the Americas: N. pulchripes, N. nigricans, N. mexicana, and N. albiseta. Chloropidae, commonly known as grass flies or frit flies, are generally associated with grasses and sedges. Species-level biology of Neodiplotoxa remains poorly documented.
Neodiplotoxa nigricans
Neodiplotoxa nigricans is a species of frit fly in the family Chloropidae, described by Loew in 1872. It belongs to the subfamily Chloropinae and tribe Diplotoxini. Members of this genus are small flies typically associated with grassland and wetland habitats. The specific epithet 'nigricans' refers to the dark or blackish coloration characteristic of this species.
Olcella
frit flies
Olcella is a genus of small frit flies in the family Chloropidae, subfamily Oscinellinae. The genus contains approximately 11 described species with highest diversity in South America, particularly Argentina. Several Nearctic species have been documented engaging in kleptoparasitism, feeding on prey fluids from insects captured by predators such as spiders, assassin bugs, and mantids. Species in this genus possess a long geniculate (elbowed) proboscis that facilitates feeding on exposed fluids without disturbing the predator.
Olcella parva
chloropid fly, frit fly
Olcella parva is a species of frit fly in the family Chloropidae, first described by Adams in 1904 under the basionym Siphonella parva. It belongs to the New World genus Olcella, which exhibits high diversity in South America. The species has been documented engaging in kleptoparasitic behavior, attracted to chemical cues from damaged or preyed-upon insects.
Olcella trigramma
Olcella trigramma is a small fly in the family Chloropidae, known primarily from South America. The genus Olcella is a New World group with high diversity in South America, and this species has been documented as a kleptoparasite, feeding on fluids from prey captured by predatory insects such as assassin bugs and spiders. Like other members of its genus, it possesses a long geniculate proboscis that facilitates feeding on exposed fluids without directly competing with the predator. The species is attracted to chemical cues, particularly defensive compounds released by heteropteran prey such as stink bugs.
Opetiophora
Opetiophora is a genus of small flies in the family Chloropidae (frit flies or grass flies), established by Loew in 1872. Members of this genus belong to the subfamily Oscinellinae, a diverse group within Chloropidae. The genus is poorly documented in scientific literature, with minimal species-level descriptions and few verified observations. Like other chloropids, these flies are likely associated with grassland or wetland habitats where their larvae develop in plant tissues or decaying organic matter.
Opetiophora straminea
Opetiophora straminea is a species of frit fly in the family Chloropidae, described by Hermann Loew in 1872. It belongs to a small genus of grass flies whose biology remains poorly documented. Records indicate it occurs in the Nearctic region.
Oscinella
frit flies
Oscinella is a genus of small flies in the family Chloropidae, commonly known as frit flies. The genus contains multiple species, several of which are significant agricultural pests of cereal crops and pasture grasses. The most economically important species is O. frit, which attacks oats, wheat, and other cereals. Species within the genus exhibit distinct flight behaviors and host plant preferences, with some being migratory and others sedentary.
Oscinellinae
grass flies
Oscinellinae is a subfamily of frit flies (family Chloropidae) comprising at least 40 genera and approximately 180 described species. Members are commonly known as grass flies and are associated primarily with monocotyledonous plants, with some species acting as secondary invaders of other plants. The subfamily has been documented engaging in kleptoparasitic behavior, feeding on fluids from prey captured by predatory insects. Species are distributed across multiple continents with documented records from Russia, Argentina, and other regions.
Oscinisoma
Oscinisoma is a genus of frit flies in the family Chloropidae, first described by Lioy in 1864. The genus comprises approximately eight described species. These small flies belong to the tribe Oscinisomatini within the subfamily Oscinellinae. Very little is known about the biology and ecology of this poorly studied genus.
Oscinisoma alienum
Oscinisoma alienum is a species of frit fly in the family Chloropidae, originally described as Elachiptera aliena by Becker in 1912. The species is placed in the tribe Oscinisomatini within the subfamily Oscinellinae. It belongs to a genus of small flies commonly known as grass flies or frit flies.
Parectecephala eucera
Parectecephala eucera is a species of frit fly in the family Chloropidae, originally described by Loew in 1863 under the genus Chlorops. It belongs to a genus of small flies commonly associated with grasses and sedges. The species has been recorded in very few observations, with only three documented occurrences in iNaturalist as of the available data.
Parectecephala maculiceps
Parectecephala maculiceps is a species of frit fly in the family Chloropidae, described by Becker in 1912. The genus Parectecephala comprises small flies associated with grassland and wetland habitats. This species is poorly documented, with only two observations recorded on iNaturalist. Like other chloropids, it likely has a close ecological association with grasses or sedges.
Pseudogaurax
Pseudogaurax is a genus of small flies in the family Chloropidae (frit flies), established by Malloch in 1915. The genus contains approximately 70 described species distributed across all biogeographic regions, with particular diversity in the Neotropics. Larvae are specialized predators and parasitoids of arthropod eggs, with well-documented associations with spider egg sacs, dobsonfly egg masses, mantid oothecae, and—uniquely among Chloropidae—ants. The genus includes the first known ant-parasitizing species in its family, Pseudogaurax paratolmos, discovered in Panama in 2016.
Pseudogaurax signatus
frit fly
Pseudogaurax signatus is a species of frit fly in the family Chloropidae, first described by Loew in 1876. The species has been documented as a parasite of spider egg sacs, specifically those of the black and yellow garden spider Argiope aurantia. This parasitic relationship was recorded in a 1993 study by Lockley and Young, which identified P. signatus as one of the chief parasites emerging from A. aurantia egg sacs alongside the ichneumon wasp Tromatopia rufopectus. The species belongs to a genus that includes other parasitoid members, with the congeneric species Pseudogaurax paratolmos being the first chloropid fly discovered to parasitize ants.
Pseudopachychaeta
grass flies
Pseudopachychaeta is a genus of grass flies in the family Chloropidae, established by Strobl in 1902. The genus contains at least one described species, P. approximatonervis. It is classified within the tribe Diplotoxini, subfamily Chloropinae. Records indicate presence in northern Europe including Denmark, Norway, and Sweden.
Rhopalopterum
frit flies
Rhopalopterum is a genus of small frit flies in the family Chloropidae, established by Duda in 1929. The genus contains approximately 10 described species distributed primarily in the Holarctic region. Species within this genus are morphologically similar to other chloropids, with most described during the late 19th and early 20th centuries. The genus is taxonomically placed within the subfamily Oscinellinae and tribe Oscinisomatini.
Rhopalopterum atriceps
Rhopalopterum atriceps is a species of frit fly in the family Chloropidae, described by Loew in 1863. The genus Rhopalopterum comprises small, often dark-colored flies associated with grasses and sedges. Like other chloropids, members of this genus are generally inconspicuous and poorly studied, with limited biological data available. The specific epithet 'atriceps' refers to the black head characteristic of this species.
Rhopalopterum carbonarium
Rhopalopterum carbonarium is a small fly species in the family Chloropidae (frit flies or grass flies), described by Hermann Loew in 1869. Members of this genus are known for their distinctive wing venation and reduced chaetotaxy. As with many Chloropidae, this species likely inhabits grassland and meadow environments, though specific ecological details remain poorly documented in the scientific literature.
Rhoptromeris
Rhoptromeris is a genus of small parasitoid wasps in the family Figitidae (subfamily Eucoilinae). Species in this genus develop as parasitoids of chloropid flies (Diptera: Chloropidae), with hosts typically inhabiting conifer cones or grass stems. The genus currently contains nine valid Holarctic species, including the type species R. heptoma, which is an important parasitoid of the frit fly Oscinella frit, a significant pest of cereal crops.
Speccafrons mallochi
Speccafrons mallochi is a species of grass fly in the family Chloropidae, first described by Sabrosky in 1938. The genus Speccafrons belongs to the tribe Siphonellini within the subfamily Oscinellinae. Like other members of Chloropidae, this species is a small true fly with reduced wing venation. The species epithet honors the dipterist John Russell Malloch.
Stenoscinis longipes
Stenoscinis longipes is a species of frit fly in the family Chloropidae, first described by Loew in 1863. The species belongs to the tribe Stenoscinini within the subfamily Oscinellinae. Very limited specific information is available about its biology and ecology.
Thaumatomyia
cereal flies, frit flies
Thaumatomyia is a genus of small flies in the family Chloropidae, commonly known as cereal flies or frit flies. The genus includes species with divergent larval ecologies: some are predatory on root aphids in agricultural soils, while others have been observed feeding on plant exudates. Several species are recognized as important biological control agents of root aphids in sugar beet and cereal crops in Middle Asia.
Thaumatomyia glabra
grass fly
Thaumatomyia glabra is a species of grass fly in the family Chloropidae, first described by Meigen in 1830. The species has been documented in Europe (Denmark, Norway, Sweden) and North America (Vermont, Hawaii). A notable behavioral trait is its attraction to methyl anthranilate, a compound found in plants such as Iris pallida.
Thaumatomyia pulla
grass fly
Thaumatomyia pulla is a species of grass fly in the family Chloropidae, first described by Adams in 1904. The genus Thaumatomyia is part of the tribe Mindini within the subfamily Chloropinae. Chloropidae, commonly known as grass flies or frit flies, are a family of small to minute flies often associated with grasses and cereal crops. This species is one of approximately 15 observations recorded in iNaturalist, suggesting it is either uncommon or underrecorded.
Thaumatomyia pullipes
Thaumatomyia pullipes is a species of frit fly in the family Chloropidae, described by Coquillett in 1898. The genus Thaumatomyia comprises small flies commonly associated with grasses and cereal crops, though specific ecological details for this species remain limited in published literature. It belongs to the tribe Mindini within the subfamily Chloropinae.
Thaumatomyia rubida
grass fly
Thaumatomyia rubida is a small grass fly in the family Chloropidae, first described by Coquillett in 1898. The species is known from California and is characterized by its yellow-orange coloration and diminutive size of 2-3 millimeters. As a member of the grass fly group, it belongs to a family commonly associated with grassland and agricultural habitats.
Tricimba brunnicollis
Tricimba brunnicollis is a species of frit fly in the family Chloropidae, first described by Becker in 1912. It belongs to the genus Tricimba, a group of small, often inconspicuous flies associated with grasses and sedges. The species is part of the subfamily Oscinellinae and tribe Tricimbini. Very few observations exist in public databases, suggesting it is either genuinely rare or under-recorded due to its small size and cryptic habits.
Tricimba lineella
frit fly
Tricimba lineella is a species of frit fly in the family Chloropidae, first described by Fallén in 1820. It is a small dipteran known from European populations. The species belongs to a genus of grass-associated flies, though specific ecological details remain poorly documented.