Horse-flies
Guides
Apatolestes
Apatolestes is a genus of horse flies in the family Tabanidae, subfamily Pangoniinae, established by Williston in 1885. The genus comprises approximately 14 recognized species distributed in North America, with some species exhibiting autogeny—the ability of females to produce an initial egg batch without a blood meal. At least one species, Apatolestes actites, has been documented as autogenous in coastal California habitats.
Atylotus
horse flies
Atylotus is a genus of horse flies in the family Tabanidae, containing approximately 15 described species. Species occur in western North America, Egypt, and parts of Europe and North America including Connecticut and Scandinavia. The genus has been subject to recent taxonomic revision, with species-level identification keys developed for regional faunas.
Catachlorops
*Catachlorops* is a genus of horse flies (family Tabanidae), established by Lutz in 1909. The GBIF backbone lists 67 named child species, alongside several placeholder entries, and records are concentrated in Central and South America. Evidence about biology is mostly species-specific: for example, two *Catachlorops* species were collected from horses in a study in Brazil’s Cerrado.
Dasybasis
Dasybasis is a genus of horse flies (Tabanidae), accepted by GBIF with authorship Macquart, 1847. Biological observations available for individual species should not be assumed to describe the whole genus. In D. pruinivitta, researchers described and illustrated the immature stages from a Central Chile wetland.
Dichelacera
Dichelacera is a Neotropical genus of horse flies (family Tabanidae), reported from Mexico south to Argentina. A 2019 species description recognized four subgenera, reflecting a genus with substantial taxonomic diversity. In a key to Neotropical horse flies, Dichelacera is distinguished by a basal facial callus about as wide as the frons and eyes that are banded or dark in life; the thorax is often transversely banded. Some species also appear in animal-health research, but species-level findings should not be generalized to the whole genus.
Elephantotus
Elephantotus is a genus of horse flies (family Tabanidae, tribe Diachlorini) described from Brazil’s Amazon coast. The original description established the genus around E. tracuateuensis and documented specimens from Pará and Maranhão; those records do not establish the genus’s full range. In that species, females are about 2 cm long and can be recognized by a reddish-brown body, bare eyes, and clear wings with brown basal cells. Its author proposed a possible association with coastal-bird nesting sites, but presented this as a hypothesis rather than a demonstrated relationship.
Fidena
Fidena is a horse-fly genus in tribe Scionini (family Tabanidae), described by Walker in 1850. GBIF recognizes about 120 taxonomic descendants, mostly species. Its recorded range is Neotropical: occurrence records are concentrated in Brazil and Costa Rica, with additional records across Central and South America. Published species accounts show striking differences in what is known about its members, from detailed female diagnoses to aquatic immature stages in bromeliads.
Leucotabanus
White Horse Flies
Leucotabanus is a genus of horse flies (family Tabanidae) established by Lutz in 1913. The genus comprises approximately 16 described species distributed primarily in the Neotropical region, with particular diversity in the Amazon basin. Members are commonly referred to as White Horse Flies. Species-level taxonomy has been revised in recent decades, with several species described by Fairchild in the mid-20th century and a new species, L. fairchildi, described in 2019.
Microtabanus
Microtabanus is a genus of horse flies in the family Tabanidae, established by Lutz in 1922. The genus contains at least one described species, M. pygmaeus. It belongs to the tribe Diachlorini within the subfamily Tabaninae. Very little is known about the biology or ecology of this poorly documented genus.
Montismyia
Montismyia is a genus of horse flies in the family Tabanidae. The genus was erected when Acellomyia lauta was transferred from Acellomyia on the basis of morphological differences and geographic distribution. GBIF currently lists one accepted species, Montismyia lauta.
Osca
Osca is a genus of horse flies in the family Tabanidae, tribe Scionini. GBIF lists 11 accepted species in the genus. Published evidence available here is species-specific rather than genus-wide, so biological details should not be generalized across Osca.
Pangoniinae
Long-tongue Horse Flies
Pangoniinae is a subfamily of horse-flies (family Tabanidae, order Diptera) comprising seven tribes and over 40 genera. Members are distinguished from other Tabanidae by the presence of ocelli and an antennal flagellum typically bearing eight rings. The subfamily includes some of the most primitive known Tabanidae, with most species being low-flying and non-bloodfeeding. Australian Pangoniinae show east coastal distribution with a secondary center in Western Australia.
Pangoniini
horse flies
Pangoniini is a tribe of horse flies (Tabanidae) within the subfamily Pangoniinae, containing some of the most morphologically primitive members of the family. Species exhibit diverse feeding strategies: some females are haematophagous (blood-feeding) while males and certain species are nectarophagous (nectar-feeding), as determined by mouthpart morphology. The tribe shows progressive evolutionary reduction in female mandibles and structural modifications of antennal and tibial characters. Australian members are predominantly low-flying insects that do not suck blood, contrasting with Chilean species that include both blood-feeding and non-blood-feeding forms.
Parosca
Parosca is a genus of horse flies (Diptera: Tabanidae), described by Enderlein in 1922; GBIF currently accepts the name and lists seven descendants. The available natural-history detail is narrower than the genus: a study describes the terrestrial larva of P. latipalpis from southern Chile. Its soil-dwelling record is a species-level example, not a known trait of every Parosca.
Phaeotabanus
Phaeotabanus is a genus of horse flies in the family Tabanidae. GBIF lists 13 accepted named species, with additional unresolved records. Occurrence records document the genus in Brazil, Peru, French Guiana, and Suriname. Field studies report host interactions for two named species, but those observations should not be generalized to every member of the genus.
Pseudoscione
Pseudoscione is a genus of horse flies (Diptera: Tabanidae), although taxonomic treatments have also placed it as a subgenus of Scaptia. Published treatments associate the group with Australia, New Guinea, New Zealand, and South America. Species-level recognition relies on taxonomic descriptions and keys rather than a single genus-wide visual character.
Scaptia
Bush flies
Scaptia is a genus of horse flies (Diptera: Tabanidae), with 55 species listed in the GBIF backbone. GBIF occurrence records are concentrated in Australia and Chile, with smaller numbers from several other countries. A described Australian species shows how varied the genus can be: Scaptia aurinigra is a small, dark fly with contrasting yellow-orange antennae.
Stonemyia
Stonemyia is a genus of horse flies in the family Tabanidae, established by Brennan in 1935. The genus contains approximately twelve described species distributed across North America, Europe, and Asia. Species within this genus are known to visit flowers for nectar feeding.
Tabaninae
horse flies
Tabaninae is a subfamily within the family Tabanidae, commonly known as horse flies. It comprises more than 3,000 described species distributed across multiple tribes including Diachlorini, Haematopotini, and Tabanini. The subfamily contains eight genera in Croatia alone, with Tabanus being the most diverse genus globally. Female horse flies are blood-feeders and significant pests of livestock, causing production losses through blood loss and nuisance biting. They also serve as mechanical vectors of animal and human pathogens including viruses, bacteria, protozoa, and helminths.
Tabanomorpha
Snipe Flies and Allies
Tabanomorpha is a brachyceran infraorder of Diptera comprising primarily two large families—Tabanidae (horse and deer flies) and Rhagionidae (snipe flies)—along with several smaller affiliated families including Athericidae, Vermileonidae, Austroleptidae, Oreoleptidae, Spaniidae, and Pelecorhynchidae. The group is notable as one of only two brachyceran lineages outside Hippoboscoidea containing blood-feeding (hematophagous) species, though they are not significant disease vectors. Phylogenetic relationships among constituent families remain unresolved.