Ephemeroptera
Guides
Chrysops cincticornis
Ring-clawed Deer Fly
Chrysops cincticornis is a deer fly in the family Tabanidae, first described by Walker in 1848. It is commonly known as the Ring-clawed Deer Fly. The species has been documented in Vermont and other parts of the United States, with 291 observations recorded on iNaturalist. Research on this species has focused on its oviposition behavior and fecundity, with laboratory studies showing females deposit eggs in gelatinous masses on mud substrates near water, averaging 156 eggs per female.
deer-flyTabanidaeDipteramedical-entomologyovipositionfecundityring-clawed-deer-flyVermontUnited-Statesmud-substrategelatinous-egg-massChrysopsinaeChrysopsiniWalker-1848iNaturalistlaboratory-rearingegg-mass156-eggsrange-42-312near-watermud-like-substrateegg-depositionreproductionbehavioral-studymedical-entomology-researchinsect-vectorsbiting-fliestabanid-flieshorse-fliesdeer-fliesChrysopsNorth-AmericaNew-Englandobservation-recordssynonym-status-in-Catalogue-of-Lifeaccepted-status-in-GBIFarthropodinsectflyBrachyceraTabanomorphaHexapodaPterygotaAnimaliaArthropodaInsectacincticornisChrysops-cincticornis-Walker-1848Chrysops-(Chrysops)-cincticornisdeerflyhorseflytabanidbiting-flyvectoroviposition-behaviorfecundity-studyJournal-of-Medical-Entomology198210.1093/jmedent/19.5.597gelatinous-secretionmudwaterlaboratory-conditionsmean-fecundityegg-productionreproductive-biologyentomologyinsect-behaviorinsect-reproductiondipterantrue-flytwo-winged-flynematoceranCyclorrhaphaAschizaSchizophoraAcalyptrataeCalyptrataeOestroideaMuscoideaHippoboscoideaGlossinidaeCalliphoridaeSarcophagidaeMuscidaeFanniidaeAnthomyiidaeScathophagidaeOestridaeTachinidaeSiphonapteraPhthirapteraHemipteraColeopteraLepidopteraHymenopteraNeuropteraMegalopteraRaphidiopteraTrichopteraStrepsipteraMecopteraDipluraProturaCollembolaZygentomaArchaeognathaEphemeropteraOdonataPlecopteraGrylloblattodeaMantophasmatodeaPhasmatodeaOrthopteraDermapteraEmbiopteraZorapteraIsopteraBlattodeaMantodeaPhyllodocidaNotopteraWalker1848speciestaxongelatinoushabitatdistributionGBIFCatalogue-of-LifeNCBIlaboratory-studybehaviorlife-cyclesubstratemud-likemeanrange42-312femaleobservationrecordspecimencollectionmuseumresearchstudyarticleabstractDOIbiologyecologyhorse-flyacceptedsynonymtaxonomyclassificationUS291-observationslaboratory291-iNaturalist-observationsGBIF-distribution-recordsaccepted-species-statussynonym-in-Catalogue-of-Life156-eggs-mean-fecundityrange-42-312-eggs1982-Journal-of-Medical-Entomology-publicationDOI-10.1093/jmedent/19.5.597entomology-researchdipteran-biologyCinygma dimicki
Cinygma dimicki is a species of flat-headed mayfly in the family Heptageniidae, described by James Halliday McDunnough in 1934. It belongs to a genus of North American mayflies characterized by distinctive head morphology adapted for clinging to substrates in flowing water. The species is known from the Nearctic region, though specific ecological details remain poorly documented in published literature.
Cinygma integrum
Cinygma integrum is a North American mayfly species in the family Heptageniidae. It is one of three Cinygma species on the continent. The life history has been studied in Oregon, where nymphs occupy submerged wood habitats year-round and adults emerge from mid-May to mid-July. The nymph is the only described member of its genus in North America.
Cinygmula
Cinygmula is a genus of flatheaded mayflies (Heptageniidae) comprising at least 30 described species. The genus is characterized by distinctive morphological features in some species, including pointed claws and a distinct frontal fold on the imago. Species occur in high-altitude alpine habitats across central Asia and the eastern Himalaya. The genus has been studied for its potential use as a bioindicator of aquatic contamination.
Cinygmula reticulata
Cinygmula reticulata is a species of mayfly in the family Heptageniidae, first described by McDunnough in 1934. It is a member of the Nearctic fauna, occurring in North America. Like other members of the genus Cinygmula, it is associated with running water habitats where the aquatic nymphs develop. The species is represented by limited observation records, with only four observations documented on iNaturalist.
Cinygmula subaequalis
flatheaded mayfly
Cinygmula subaequalis is a flatheaded mayfly species in the family Heptageniidae. It is distributed across northern North America, including Alaska, northern Canada, and the eastern United States. The species belongs to a genus characterized by distinctive head morphology. Limited observational data suggests it is rarely encountered.
Diphetor
Diphetor is a genus of small mayflies in the family Baetidae, established by Waltz and McCafferty in 1987. These insects belong to the order Ephemeroptera, characterized by their short adult lifespan and aquatic nymphal stages. The genus is part of the diverse Baetidae family, one of the largest families of mayflies.
Diphetor hageni
Hagen's Small Minnow Mayfly
Diphetor hageni is a small mayfly species in the family Baetidae, commonly known as Hagen's Small Minnow Mayfly. It is native to the Nearctic region, primarily distributed across North America. The species is part of the diverse Baetidae family, which are among the most abundant and widespread mayflies in running waters.
Drunella
Blue-winged Olives, Spiny Crawler Mayflies
Drunella is a genus of spiny crawler mayflies in the family Ephemerellidae, comprising at least 20 described species. These mayflies are aquatic insects with nymphs that inhabit stream environments and are significant components of freshwater food webs. Adults are important to fly fishermen, who commonly refer to them as "Blue-winged Olives" and imitate them with artificial flies. Some species, such as Drunella grandis (the green drake), are particularly valued as trout food sources.
Drunella coloradensis
Small Western Green Drake
Drunella coloradensis is a species of spiny crawler mayfly in the family Ephemerellidae, commonly known to anglers as the Small Western Green Drake. The species is found in freshwater streams across western North America, with a range extending from Alaska and northern Canada through the western United States to northern Mexico and Central America. Nymphs are known to alter their behavior in response to short-term pH reductions, becoming more active under acidic conditions. The species is of particular importance to fly fishermen, who imitate its various life stages with artificial flies.
Drunella cornutella
spiny crawler mayfly
Drunella cornutella is a species of spiny crawler mayfly in the family Ephemerellidae, originally described by McDunnough in 1931 as Ephemerella cornutella. It is found in North America, with records from the Nearctic region including the northeastern United States. Like other members of the genus Drunella, it is an aquatic insect with immature stages living in freshwater habitats.
Drunella spinifera
Western Slate Olive
Drunella spinifera is a species of spiny crawler mayfly in the family Ephemerellidae. It is found in southwestern and northern Canada, the western United States, and Alaska. The common name "Western Slate Olive" reflects its regional distribution and likely coloration. Like other members of the genus Drunella, it belongs to a group of mayflies commonly targeted by fly fishermen, though specific angling references for this species are limited.
Drunella walkeri
Small Blue-winged Olive
Drunella walkeri is a species of spiny crawler mayfly in the family Ephemerellidae, commonly known as the Small Blue-winged Olive among anglers. It is found in North America and is one of the mayfly species frequently imitated by fly fishermen. The species was first described by Eaton in 1884.
Ecdyonurus
Ecdyonurus is a genus of mayflies in the family Heptageniidae, comprising approximately 66 described species distributed primarily across Europe and parts of North Africa and Asia. The genus is taxonomically well-studied, with multiple species described in recent decades from mountain regions including the Carpathians, Crimean Peninsula, and Aurès Mountains. Species within this genus are typically associated with running waters and have been subjects of ecological studies on larval growth and thermal biology.
Epeorus albertae
flatheaded mayfly
Epeorus albertae is a flatheaded mayfly in the family Heptageniidae, distributed across northern and western North America. Laboratory studies indicate that nymphal growth rate and activity are strongly temperature-dependent, with optimal growth occurring at 15°C compared to slower development at lower temperatures. Nymphs exhibit behavioral thermoregulation by seeking refugia at cold temperatures, suggesting adaptation to thermally variable stream environments.
Epeorus fragilis
flatheaded mayfly
Epeorus fragilis is a species of flatheaded mayfly in the family Heptageniidae, first described by Morgan in 1911. It is distributed across North America. As a member of the order Ephemeroptera, it undergoes aquatic larval development before emerging as a short-lived adult.
Epeorus longimanus
flatheaded mayfly
Epeorus longimanus is a flatheaded mayfly species in the family Heptageniidae. Nymphs inhabit stream riffles and show specific microhabitat preferences, being more abundant in areas with smaller sediment sizes, higher live periphyton biomass, and lower densities of invertebrate predators. The species is distributed across western North America from Alaska through the western United States to southwestern and northern Canada.
Epeorus pleuralis
Quill Gordon
Epeorus pleuralis, commonly known as the Quill Gordon, is a flatheaded mayfly in the family Heptageniidae. It is native to North America and is recognized as an important species in aquatic entomology and fly fishing. The species is known for its relatively early emergence in the spring, making it a significant hatch for anglers in eastern North American streams.
Epeorus punctatus
Epeorus punctatus is a species of flat-headed mayfly in the family Heptageniidae. The species was originally described by McDunnough in 1925 under the genus Iron before being transferred to Epeorus. It is known from North America within the Nearctic region. Like other members of the genus, it likely inhabits flowing water environments where the nymphs cling to submerged substrates.
Ephemera guttulata
Eastern Green Drake, Shad Fly, Coffinfly
Ephemera guttulata, commonly known as the eastern green drake, is a burrowing mayfly species native to eastern North America. It is one of the largest mayfly species in the region and is highly significant to fly fishing, where its emergence events are eagerly anticipated. The species has a fully aquatic larval stage, followed by a winged subimago (dun) stage and a short-lived sexually mature adult (imago) stage. Its conservation status is G5 (secure) according to NatureServe.
Ephemera simulans
Brown Drake
Ephemera simulans is a burrowing mayfly species in the family Ephemeridae, commonly known as the Brown Drake. It is widely distributed across North America, particularly common in the Rocky Mountains, Midwest, and Great Lakes region. The species is economically significant in recreational fly fishing, where both nymph and adult stages are imitated with artificial flies. Nymphs inhabit sand and silt substrates of lakes and streams, emerging as adults primarily at night from mid-June to mid-July.
Ephemera varia
Yellow Drake
Ephemera varia, commonly known as the Yellow Drake, is a species of burrower mayfly in the family Ephemeridae. It is native to North America, with documented presence in the northeastern United States including Vermont. Like other members of its genus, it is associated with aquatic environments and has a brief adult lifespan. The species is represented by 59 observations on iNaturalist, indicating it is documented but not extensively studied.
Ephemerella aurivillii
spiny crawler mayfly
Ephemerella aurivillii is a spiny crawler mayfly in the family Ephemerellidae with a strict one-year life cycle. The species occurs across northern regions of the Northern Hemisphere, including Europe, northern Asia, and North America. Research in Norway demonstrated that its distribution and growth rates are strongly temperature-dependent, with populations expanding following hydropower-induced warming of previously cold streams.
Ephemerella dorothea infrequens
Pale Morning Dun
Ephemerella dorothea infrequens is a subspecies of mayfly in the family Ephemerellidae, commonly known as the Pale Morning Dun. It is an aquatic insect whose nymphal stage inhabits freshwater environments. The species is recognized as an important food source for trout and is frequently imitated by fly fishers using artificial flies. It was described by McDunnough in 1924 and is accepted as a valid subspecies within the Ephemerella dorothea complex.
Ephemerella excrucians
Pale Morning Dun
Ephemerella excrucians, commonly known as the pale morning dun, is a species of spiny crawler mayfly in the family Ephemerellidae. It is distributed across all of Canada and the continental United States. The species is of particular interest to fly fishers due to its importance as a trout food source and its frequent use as a model for artificial flies.
Ephemerella invaria
Sulphur Dun
Ephemerella invaria, commonly known as the sulphur dun, is a species of spiny crawler mayfly in the family Ephemerellidae. It occurs in headwater streams across eastern North America, from southeastern and northern Canada through the eastern United States. The species has been studied for population genetic impacts associated with deforestation of its stream habitats. As a member of the Ephemerellidae, it belongs to a group of mayflies characterized by distinctive spiny or tuberculate body features.
Ephemerella subvaria
red quill, Dark Hendrickson
Ephemerella subvaria is a spiny crawler mayfly in the family Ephemerellidae. The species was described by McDunnough in 1931. It is widely distributed in the eastern United States with limited occurrence in the upper Midwest. A 2019 record from Ohio represents the first state documentation, with specimens reared from nymphs collected in March to adult emergence in late April.
Ephemerella tibialis
Little Western Dark Hendrickson
Ephemerella tibialis is a species of spiny crawler mayfly described by McDunnough in 1924. It belongs to the family Ephemerellidae, a group known for their distinctive spiny or tuberculate body ornamentation. The species is found in North America and is recognized among anglers by the common name Little Western Dark Hendrickson, indicating its importance as a model organism for fly-fishing.
Ephemerella verruca
Ephemerella verruca is a species of mayfly in the family Ephemerellidae, described by Allen and Edmunds in 1965. It belongs to the order Ephemeroptera, a group of aquatic insects commonly known as mayflies. The species is recorded from the Nearctic region, specifically North America. Like other members of its genus, it has an aquatic larval stage and terrestrial adult stage.
Ephemerellidae
Spiny Crawler Mayflies
Ephemerellidae, commonly known as spiny crawler mayflies, is a family of mayflies (Ephemeroptera) comprising approximately 90 species across 8-14 genera. The family is distributed throughout North America and the UK, with additional records from Europe and Asia. Nymphs inhabit lotic-erosional environments including flowing streams of all sizes, lake shores, and beaches with wave action. They are primarily collector-gatherers and serve as important indicators of water quality due to their sensitivity to pollution.
Ephemeridae
Burrowing Mayflies
Ephemeridae is a family of large mayflies comprising approximately 150 described species distributed worldwide except Australia and Oceania. Adults range up to 35 mm in length and possess either two or three elongated caudal filaments. Many species exhibit distinctively patterned wings. The family is commonly known as "burrowing mayflies" due to the fossorial adaptations of their nymphs, which inhabit silty or sandy substrates in freshwater systems. Nymphs possess specialized morphological features including spur-like projections on foretibiae, dorsally positioned plumose and lanceolate abdominal gills, and mandibular tusks that facilitate burrowing behavior.
Ephoron leukon
white fly
Ephoron leukon, commonly known as the white fly, is a species of pale burrower mayfly in the family Polymitarcyidae. Nymphs are burrowing and inhabit tubular burrows associated with stones in river rapids, particularly in fine silt deposits. The species undergoes dramatic morphological changes during early nymphal development, including specialized mouthpart modifications for filter feeding and progressive elaboration of abdominal gills.
Eurylophella bicolor
bicolor spiny crawler mayfly
Eurylophella bicolor is a species of spiny crawler mayfly in the family Ephemerellidae, originally described as Ephemerella bicolor by Clemens in 1913. The species is distributed across the Nearctic region, particularly in North America. Like other members of the genus Eurylophella, it is associated with freshwater aquatic habitats during its nymphal stages.
Eurylophella funeralis
Eurylophella funeralis is a mayfly species in the family Ephemerellidae, described by McDunnough in 1925. Originally placed in the genus Ephemerella, it was later transferred to Eurylophella. The species is known from the Nearctic region, with records from North America including Vermont. As a member of the order Ephemeroptera, it has an aquatic larval stage and terrestrial adult stage, though specific ecological details for this species remain limited in available literature.
Eurylophella lodi
Eurylophella lodi is a species of spiny crawler mayfly in the family Ephemerellidae, described by Mayo in 1952. It belongs to a genus of mayflies found in North America. The species is known from limited observations, with only two documented occurrences in iNaturalist. Like other members of Ephemerellidae, it is likely associated with freshwater aquatic habitats during its immature stages.
Eurylophella prudentalis
spiny crawler mayfly
Eurylophella prudentalis is a species of spiny crawler mayfly in the family Ephemerellidae, first described by James Halliday McDunnough in 1931. As a member of the genus Eurylophella, it belongs to a group of mayflies commonly known as spiny crawlers, characterized by their distinctive body armature. The species is known from North America, with documented occurrences in the northeastern United States including Vermont. Like other Ephemerellidae, it completes its aquatic larval development in freshwater habitats before emerging as a short-lived adult.
Fallceon quilleri
Fallceon quilleri is a small minnow mayfly in the family Baetidae, described by Dodds in 1923. It is known from a relatively small number of observations (15 records on iNaturalist). The species has a broad transcontinental distribution spanning temperate and tropical regions of the Americas.
Heptagenia
flatheaded mayflies
Heptagenia is a genus of flatheaded mayflies in the family Heptageniidae, containing at least 20 described species. Nymphs are primarily benthic inhabitants of lotic systems, where they construct burrows in sandy or gravelly substrates and employ filter-feeding mechanisms. Adults are distinguished from the related genus Raptoheptagenia by the absence of anastomosed crossveins in the stigmatic area of the forewing and by having foretarsi shorter than the tibiae. The genus has been documented across North America, Europe, and Asia, including the Western Himalaya.
Heptagenia adaequata
Heptagenia adaequata is a species of flatheaded mayfly in the family Heptageniidae. Described by James Halliday McDunnough in 1924, it is a Nearctic species found in North America. Like other members of its genus, it is associated with running water habitats. The species is represented by relatively few observations in biodiversity databases.
Heptagenia flavescens
flatheaded mayfly
Heptagenia flavescens is a species of flatheaded mayfly in the family Heptageniidae. The species has been documented in North America and Central America, with records indicating a southwestern range extension. As with other members of Heptageniidae, it possesses the characteristic flattened head morphology associated with this group of mayflies.
Heptagenia marginalis
Margined Flat-headed Mayfly
Heptagenia marginalis is a species of flatheaded mayfly in the family Heptageniidae, first described by Banks in 1910. It belongs to a family characterized by dorsoventrally flattened body forms adapted to clinging in fast-flowing water. The species is known from North America, though detailed biological information remains limited in available literature.
Heptagenia pulla
dusky flat-headed mayfly
Heptagenia pulla is a species of flat-headed mayfly in the family Heptageniidae, commonly known as the dusky flat-headed mayfly. The species was described by Clemens in 1913 and is native to the Nearctic region. Like other members of its genus, it is associated with flowing freshwater habitats. The specific epithet "pulla" refers to the dusky or dark coloration characteristic of this species.
Heptagenia solitaria
solitary flat-headed mayfly
Heptagenia solitaria is a species of flatheaded mayfly in the family Heptageniidae, first described by McDunnough in 1924. The species is distributed across southwestern and northern Canada and the western United States. As a member of the Heptageniidae, it belongs to a family of mayflies commonly known as flatheaded mayflies due to their distinctive head morphology.
Heptageniidae
Stream Mayflies, Flat-headed Mayflies
Heptageniidae is a family of mayflies comprising over 500 described species, commonly known as stream mayflies or flat-headed mayflies. Members are generally small with three long tails, clear wings with prominent venation, and males possess large compound eyes that are not divided into upper and lower parts. The family is primarily distributed across the Holarctic, Oriental, and Afrotropical regions, with additional presence in Central American tropics and extreme northern South America. Nymphs are flattened in shape, typically dark in coloration, and inhabit fast-flowing streams where they exhibit diverse feeding strategies including herbivory, scavenging, and predation.
Heptagenioidea
Heptagenioidea is a superfamily of mayflies (Ephemeroptera) distributed across most global regions except the Arctic and Antarctic. The superfamily likely originated in the Jurassic period, coinciding with a shift from still-water to flowing-water breeding habitats. This ecological transition drove rapid radiation and morphological adaptations, including modifications to mouthparts and forelegs for passive feeding in current. Heptageniidae represents the most widely distributed family within this group.
Heterocloeon
small minnow mayflies
Heterocloeon is a genus of small minnow mayflies in the family Baetidae, containing approximately nine described species. These mayflies are part of the diverse Baetidae family, which is one of the largest families of mayflies. The genus was established by McDunnough in 1925. Species within this genus have been studied in relation to environmental modifications, particularly the effects of reservoir impoundment on their life history.
Heterocloeon curiosum
curious small minnow mayfly
Heterocloeon curiosum is a small minnow mayfly in the family Baetidae, native to North America. It has been studied in Virginia river systems, where it demonstrates bivoltine life history with two summer generations. Reservoir construction with surface release can significantly alter its emergence timing, larval density, and fecundity through thermal regime changes.
Heterocloeon petersi
small minnow mayfly
Heterocloeon petersi is a small minnow mayfly species in the family Baetidae, first described by Müller-Liebenau in 1974. It is recorded from the southeastern United States. As a member of Baetidae, it belongs to one of the most diverse families of mayflies, though specific biological details for this species remain limited in published literature.
Homoeoneuria
brushleg mayflies
Homoeoneuria is a genus of brushleg mayflies in the family Oligoneuriidae, established by Eaton in 1881. The genus contains at least five described species, with confirmed records in North America (including the type species H. salviniae) and South America (Brazil, Peru, Argentina, and Colombia). A new species, H. (H.) watu, was described from Southeastern Brazil based on distinctive adult and nymphal morphological characters. The genus is poorly documented in northern South America, with recent confirmations extending its known range.
Homoeoneuria alleni
Homoeoneuria alleni is a species of mayfly (Ephemeroptera) in the family Oligoneuriidae, described by Pescador & Peters in 1980. The genus Homoeoneuria is part of the heptagenioid lineage of mayflies. This species is known from the Nearctic region, with records from North America and Middle America.