Megaloptera
Guides
Chauliodes
Spring and Summer Fishflies
Chauliodes is a genus of fishflies in the family Corydalidae, commonly known as spring and summer fishflies. The genus contains approximately five described species distributed in North America, including the well-known spring fishfly (C. rastricornis) and summer fishfly (C. pectinicornis). Adults are nocturnal and frequently attracted to lights. The genus is distinguished from other fishflies by specific antennal and wing characteristics.
Chauliodes pectinicornis
Summer Fishfly
Chauliodes pectinicornis, commonly known as the Summer Fishfly, is a species of fishfly in the family Corydalidae native to eastern North America. First described by Carl Linnaeus in 1763, this species has a notably wide distribution across eastern Canada and the United States. A distinctive ecological feature is its commensal relationship with Plecopteracoluthus downesi larvae, which complete their entire life cycle including pupation on the fishfly's mesothorax.
Chauliodes rastricornis
Spring Fishfly
Chauliodes rastricornis, commonly known as the spring fishfly, is a species of fishfly in the family Corydalidae. It is one of the most frequently observed fishflies in North America, with over 13,000 records on iNaturalist. Adults are active in spring, distinguishing them from summer-active relatives. The species belongs to the order Megaloptera, an ancient lineage of aquatic insects.
Chauliodinae
Fishflies
Fishflies (subfamily Chauliodinae) are large, winged insects in the megalopteran family Corydalidae. Adults are distinguished from their close relatives, dobsonflies, by their relatively unremarkable mandibles and feathery antennae in males. Larvae are aquatic predators that inhabit clean, flowing streams, where they prey on other aquatic insects and small vertebrates. The subfamily contains approximately 15 genera and nearly 110 species distributed across North America, South America, Africa, Australia, and Asia.
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-biologyCorydalidae
Dobsonflies and Fishflies
Corydalidae is a family of large megalopteran insects commonly known as dobsonflies and fishflies. Adults typically exceed 25 mm in body length and possess long filamentous antennae—feathered in male fishflies—and four large, translucent, smoky-grey wings with the anterior pair slightly longer than the posterior. The family is divided into two subfamilies: Corydalinae (dobsonflies), whose males bear distinctive elongated mandibles used in combat, and Chauliodinae (fishflies), whose males have normal mandibles. Aquatic larvae, called hellgrammites, are predatory and possess strong sharp mandibles and abdominal branchial filaments for respiration. They develop over one to three years before leaving water to pupate in terrestrial chambers dug under stones or logs.
Corydalinae
Dobsonflies
Corydalinae is a subfamily of large megalopteran insects commonly known as dobsonflies. Adults are among the largest winged insects in their range, with males of some species possessing dramatically elongated mandibles used in intraspecific combat. Larvae, called hellgrammites, are aquatic predators inhabiting clean, fast-flowing streams. The subfamily contains nine genera distributed across the Americas, Asia, and South Africa, with notable Oriental genera including Neurhermes and Nevromus. Some Corydalinae species exhibit striking coloration patterns that likely represent Batesian mimicry of diurnal toxic moths.
Corydalus
dobsonflies, hellgrammites (larvae), go-devil, grampus
Corydalus is a genus of large flying insects in the family Corydalidae, commonly known as dobsonflies. The genus contains approximately 35 species endemic to North, Central, and South America. Adults are among the largest winged insects in their range, with wing lengths reaching up to 85 millimetres. The genus exhibits pronounced sexual dimorphism: males possess greatly elongated, sickle-shaped mandibles used in male-male combat and to grasp females during mating, while females have smaller but still formidable jaws capable of delivering a painful bite. The aquatic larvae, known as hellgrammites, are predatory and serve as important indicators of stream health.
Corydalus cornutus
Eastern Dobsonfly, Hellgrammite (larval form), Go-devil, Grampus
Corydalus cornutus, the eastern dobsonfly, is among the largest insects in eastern North America, with adults reaching 140 mm in length and wingspans up to 130 mm. The species exhibits pronounced sexual dimorphism: males possess elongated, sickle-shaped mandibles up to 40 mm long used in combat with rivals, while females have shorter, powerful mandibles capable of delivering a painful bite. The aquatic larval stage, known as hellgrammites, are apex invertebrate predators in fast-flowing streams, feeding on other aquatic insects for one to three years before emerging to pupate in terrestrial soil chambers. Adults are short-lived, non-predatory, and primarily nocturnal, attracted to lights near waterways.
Corydalus luteus
hellgrammite, dobsonfly
Corydalus luteus is a species of dobsonfly in the family Corydalidae, found across the Americas from the United States through Central America to South America. Adults are large, spectacular insects with prominent mandibles—greatly elongated in males, shorter but powerful in females. The larvae, known as hellgrammites, are aquatic predators inhabiting streams and rivers. The species is attracted to lights at night and is occasionally encountered by entomologists during field surveys.
Corydalus texanus
Western Dobsonfly
Corydalus texanus is a large megaloopteran insect commonly known as the Western Dobsonfly. Adults are among the largest winged insects in their range, with males distinguished by elongated sickle-shaped mandibles used in combat with rivals. Females possess shorter but powerful jaws capable of delivering a painful bite. The aquatic larval stage, known as hellgrammites, are predaceous and serve as important indicators of stream health. Adults are attracted to lights and may be observed near water bodies at night.
Dysmicohermes
Dysmicohermes is a genus of fishflies in the family Corydalidae, established by Munroe in 1953. The genus contains two described species: Dysmicohermes disjunctus and Dysmicohermes ingens. As members of Megaloptera, these insects represent a relatively small and ancient order of holometabolous insects. The genus is part of the diverse Corydalidae family, which includes some of the largest aquatic insects in North America.
Neohermes
Gray Fishflies
Neohermes is a genus of fishflies in the family Corydalidae containing approximately five described species. Species in this genus are aquatic insects associated with freshwater habitats, particularly intermittent streams. The genus is known for including long-lived aquatic species with specialized burrowing behaviors.
Neohermes angusticollis
narrow-collared fishfly
Neohermes angusticollis is a fishfly species in the family Corydalidae, order Megaloptera. It occurs in North America. As with other fishflies, adults are typically nocturnal and are attracted to lights. The genus Neohermes is distinguished from related genera by features of the male genitalia and wing venation.
Neohermes californicus
California fishfly
Neohermes californicus is a species of fishfly in the family Corydalidae, first described by Walker in 1853 as Chauliodes californicus. It belongs to the order Megaloptera, a small group of primitive holometabolous insects that includes fishflies, dobsonflies, and alderflies. The species is found in North America, particularly in western regions including California. Fishflies in this genus are associated with aquatic habitats during their larval stages. Adults are typically nocturnal and attracted to lights.
Neohermes concolor
fishfly
Neohermes concolor is a species of fishfly in the family Corydalidae, order Megaloptera. It is found in North America, with distribution records from the United States including Vermont. The species was originally described by K. Davis in 1903 under the basionym Chauliodes concolor before being transferred to the genus Neohermes. Fishflies in this family are characterized by their elongated bodies, large membranous wings, and aquatic larval stages.
Neohermes filicornis
Fishfly
Neohermes filicornis is a long-lived aquatic fishfly (Megaloptera: Corydalidae) inhabiting intermittent streams across North America. The species exhibits burrowing behavior and is adapted to temporary water systems with periodic drying. Adults are terrestrial while larvae are aquatic predators with extended larval development periods.
Neohermes inexpectatus
Neohermes inexpectatus is a species of dobsonfly in the family Corydalidae, described in 2016 from China. As a member of the genus Neohermes, it belongs to a group of relatively small dobsonflies with reduced adult mouthparts. The species was described by Liu and Winterton based on morphological characters distinguishing it from congeners. Like other megalopterans, it likely has an aquatic larval stage and terrestrial adult stage.
Nigronia
Dark Fishflies
Nigronia is a genus of megalopteran insects commonly known as dark fishflies. The genus contains two species, Nigronia serricornis and Nigronia fasciata, distinguished primarily by wing pattern. Adults are medium-sized insects measuring 20-30 millimeters in length. The genus belongs to the family Corydalidae, which includes dobsonflies and fishflies.
Nigronia fasciata
Banded Dark Fishfly
Nigronia fasciata is a species of dark fishfly in the family Corydalidae, order Megaloptera. Adults measure 22–28 mm in body length. The species occurs in the eastern United States and is not present in Canada. Like other fishflies, it has aquatic larval stages and terrestrial adults.
Orohermes crepusculus
Orohermes crepusculus is a species of fishfly in the family Corydalidae, originally described as Dysmicohermes crepusculus by Chandler in 1954. It is one of several species in the genus Orohermes, which comprises small to medium-sized megalopterans found in western North America. The species epithet "crepusculus" refers to twilight, possibly alluding to crepuscular activity patterns. Adults are weak fliers and are often attracted to lights.
Protochauliodes aridus
Protochauliodes aridus is a species of fishfly in the family Corydalidae, described by Maddux in 1954. It is one of approximately 20 species in the genus Protochauliodes, which are distributed primarily in North America. The specific epithet 'aridus' suggests an association with arid or dry environments, though this has not been explicitly documented. As with other fishflies, adults are likely nocturnal and attracted to lights.
Protochauliodes minimus
small fishfly
Protochauliodes minimus is a small fishfly species in the family Corydalidae, order Megaloptera. The species was described by K. Davis in 1903 and is native to North America. Like other fishflies, it belongs to an ancient lineage of holometabolous insects with aquatic larval stages. The specific epithet "minimus" suggests it is among the smaller members of its genus.
Protosialis glabella
Protosialis glabella is a species of alderfly in the family Sialidae, order Megaloptera. The genus Protosialis represents one of several genera within Sialidae, a family of aquatic insects whose larvae are predatory and develop in freshwater habitats. Adults are typically nocturnal and short-lived, with reduced mouthparts and a primary focus on reproduction. The species was described by Ross in 1937. Megalopterans as a group are considered primitive holometabolous insects, retaining many ancestral characteristics.
Sialis iola
Sialis iola is a species of alderfly described by Ross in 1937. As a member of the family Sialidae, it belongs to the order Megaloptera, a small group of aquatic insects closely related to dobsonflies and fishflies. The species is known to occur in North America, though specific details about its biology and ecology remain poorly documented. Like other alderflies, its larvae are presumed to be aquatic predators in freshwater habitats.
Sialis itasca
Sialis itasca is a species of alderfly in the family Sialidae, described by Ross in 1937. As a member of the order Megaloptera, it belongs to a small group of primitive holometabolous insects. The species is known from North America, with minimal observational records available. Like other alderflies, adults are associated with riparian habitats near the aquatic environments where their larvae develop.
Sialis mohri
alderfly
Sialis mohri is a species of alderfly in the family Sialidae, described by Ross in 1937. It is found in North America. Like other alderflies, it belongs to the order Megaloptera, a small group of aquatic insects whose larvae are predatory and develop in freshwater habitats. The species name honors Dr. Charles Mohr, an entomologist who collected the type specimens.
Sialis nevadensis
Sialis nevadensis is a species of alderfly in the family Sialidae, order Megaloptera. It was described by K. Davis in 1903 and is native to North America. The genus Sialis comprises aquatic insects whose larvae are predatory and develop in freshwater environments. Adults are typically found near streams and rivers during their brief aerial phase.