Chauliodinae

Fishflies

Genus Guides

Chauliodes(Spring and Summer Fishflies)
Dysmicohermes
Neohermes(Gray Fishflies)
Nigronia(Dark Fishflies)
Orohermes
Protochauliodes

Fishflies ( Chauliodinae) are large, winged insects in the megalopteran Corydalidae. are distinguished from their close relatives, dobsonflies, by their relatively unremarkable and feathery in males. Larvae are aquatic that inhabit clean, flowing streams, where they prey on other aquatic insects and small vertebrates. The subfamily contains approximately 15 and nearly 110 distributed across North America, South America, Africa, Australia, and Asia.

Chauliodinae by (c) Don Loarie, some rights reserved (CC BY), uploaded by Don Loarie. Used under a CC-BY license.

Chauliodes rastricornis P1490863a by
xpda. Used under a CC BY-SA 4.0 license.

Chauliodes pectinicornis 293405486 by Pete Grannis. Used under a CC BY 4.0 license.

Pronunciation

How to pronounce Chauliodinae: //kaʊliːoʊˈdɪnaɪ//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from dobsonflies ( Corydalinae) by: (1) —fishflies lack the greatly enlarged, sickle-shaped mandibles characteristic of male dobsonflies; and (2) —male fishflies have conspicuously feathery (pectinate) antennae, while antennae are relatively simple. Distinguished from other large aquatic insects by the combination of large size, net-veined wings, and aquatic larval . Chauliodes pectinicornis, the 'summer fishfly,' is a well-known North American representative.

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Habitat

Larvae inhabit clean, flowing freshwater streams and rivers, typically in spaces among stones and vegetation. They require well-oxygenated water and are indicators of stream health, absent from polluted waters. are found on vegetation near water and are attracted to lights. occurs in terrestrial environments in moist, protected locations such as under stones, logs, or bark near stream banks.

Distribution

Widespread across multiple continents. New World include Dysmicohermes, Orohermes, Neohermes, Nothochauliodes, Protochauliodes, Archichauliodes, Chauliodes, and Nigronia (North and South America). Three genera are to the Afrotropical Realm (Madagascar and South Africa): Platychauliodes, Madachauliodes, and Taeniochauliodes. Archichauliodes and Protochauliodes occur in the Australian Realm. endemics include Anachauliodes, Ctenochauliodes, Neochauliodes, and Parachauliodes.

Seasonality

are active during late spring and summer. Chauliodes pectinicornis, the 'summer fishfly,' emerges in summer. Mass emergences of adults can occur, with adults living up to approximately seven days as largely non-feeding individuals.

Diet

Larvae are predatory, feeding on aquatic insects including mayflies, stoneflies, and , as well as small vertebrates such as minnows and tadpoles. Some larvae are , consuming aquatic plants in addition to animal material. lack functional mouthparts and do not feed.

Life Cycle

are laid on vegetation overhanging streams; upon hatching, larvae drop into the water. Larval development spans one to three years. When ready to pupate, larvae crawl out of water to construct pupal chambers in moist terrestrial cavities. emerge from pupae, live briefly (approximately seven days), mate, and die. The entire lifespan is several years, with most time spent as larvae.

Behavior

Larvae are active that roam stream bottoms. They can deliver a painful bite when handled. are attracted to light and may be found near illuminated buildings at night. Males use their feathery to detect female . Mass emergences can produce spectacular swarms near bodies of water.

Ecological Role

Larvae function as important in aquatic , regulating of other aquatic insects. They serve as key indicators of clean freshwater , with their presence signaling good water quality. Larvae are significant prey for fish and are used as by anglers. provide food for birds, amphibians, and other during events.

Human Relevance

Larvae (hellgrammites) are valued as excellent live for sport fishing, particularly for bass and trout. swarms can be a nuisance near lakes and rivers, coating surfaces and creating slippery conditions on roads. The Bay-Rama Festival in Michigan celebrates /fishfly emergences. Some have been studied cytogenetically, revealing unique mechanisms.

Similar Taxa

Corydalinae (dobsonflies)Distinguished by male dobsonflies' greatly enlarged, sickle-shaped used in combat; are not feathery. Both share large size and aquatic larvae.
Ephemeroptera (mayflies)Mayflies also have aquatic larvae and mass emergences, but have short, bristle-like , triangular forewings, and typically three long caudal filaments. Fishflies have net-veined wings and feathery or thread-like antennae.

Misconceptions

Regional colloquialism causes confusion: around Lake St. Clair, Michigan, burrowing mayflies (Hexagenia limbata) are locally called 'fishflies' due to their fishy odor, though these are unrelated ephemeropterans. True fishflies (Chauliodinae) are megalopterans, not mayflies.

More Details

Cytogenetics

Four North American have been karyotyped: Dysmicohermes disjunctus, D. ingens, and Orohermes crepusculus (western) have 2n=22 (10 autosomal pairs + XY); Nigronia serricornis (eastern) has n=10 in with a parachute-type sex bivalent (Xyp). This parachute mechanism is shared with Corydalinae and Coleoptera.

Fossil Record

Extinct include †Cretochaulus (Early Cretaceous, Russia), †Eochauliodes, and †Jurochauliodes (Middle/Late Jurassic, China), indicating ancient diversification of the .