Aquatic-insects
Guides
Diplectrona
diplectronan caddisflies
Diplectrona is a genus of net-spinning caddisflies in the family Hydropsychidae, containing over 100 described species distributed across multiple continents. The genus exhibits considerable morphological diversity in both larvae and adults, with larvae inhabiting various lotic freshwater habitats. Recent studies have revealed cryptic diversity within currently recognized species, particularly in North America, suggesting the genus requires taxonomic revision. Species occur in Asia, Europe, North America, and other regions, with new country records continuing to be documented.
Diplocladius
Diplocladius is a genus of non-biting midges in the bloodworm family Chironomidae. It belongs to the subfamily Orthocladiinae, a diverse group of chironomid midges commonly found in aquatic and semi-aquatic environments. The genus was established by Kieffer in 1908 and contains four recognized species. These midges are part of the benthic macroinvertebrate communities of freshwater systems.
Diploperlini
springflies
Diploperlini is a tribe of springflies (Plecoptera) in the family Perlodidae, established by Stark & Szczytko in 1984. The tribe comprises approximately 13 genera and more than 30 described species. Members of this tribe are aquatic insects in the nymphal stage and terrestrial as adults.
Dixa
Dixa is a genus of non-biting midges in the family Dixidae, established by Johann Wilhelm Meigen in 1818. The genus has cosmopolitan distribution, with species recorded across Europe, North America, and other regions. Species-level taxonomy within Dixa has been subject to recent revision, with several new species described from North America and taxonomic confusion resolved for historically problematic names such as D. modesta. Larvae develop in aquatic environments, particularly lotic (flowing water) habitats.
Djalmabatista
Djalmabatista is a genus of non-biting midges (Chironomidae) established by Fittkau in 1968. The genus belongs to the subfamily Tanypodinae and tribe Procladiini. Approximately 14 species have been described. These midges are aquatic in their larval stages and are part of the diverse chironomid fauna found in freshwater habitats.
Donaciinae
Aquatic Leaf Beetles, Reed Beetles
Donaciinae is a subfamily of leaf beetles (Chrysomelidae) comprising approximately 100 species across six genera, including Donacia, Macroplea, and Plateumaris. Members are strongly associated with aquatic and semi-aquatic habitats, with larvae developing underwater attached to plant roots. The subfamily is characterized by distinctive morphological adaptations and an obligate symbiosis with bacteria that produce the silk-like material used to construct waterproof pupal cocoons. Donaciinae are primarily distributed in the Northern Hemisphere with extensions into Africa, Madagascar, and Australasia.
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.
Dytiscinae
predaceous diving beetles
Dytiscinae is a subfamily of predaceous diving beetles (family Dytiscidae) containing at least 20 genera and approximately 380 described species. Members are medium to large diving beetles found in aquatic habitats across most continents. The subfamily includes well-known genera such as Dytiscus, Cybister, Acilius, and Hydaticus. Species are predatory in both adult and larval stages, with larvae often called 'water tigers' for their voracious feeding habits.
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.
Elliptera
Elliptera is a genus of crane flies in the family Limoniidae, established by Schiner in 1863. The genus comprises ten described species distributed across the Holarctic region, including North America, Europe, and East Asia. Immature stages have been described for only a few species, with larvae inhabiting aquatic, hygropetric environments on wet rocks in mountainous areas.
Endochironomus
Endochironomus is a genus of non-biting midges in the bloodworm family Chironomidae. The genus was established by Kieffer in 1918 and contains at least six described species distributed across Europe and North America. Members belong to the subfamily Chironominae and tribe Chironomini. As with other chironomid midges, adults do not feed and lack functional mouthparts.
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.
Ephemeroptera
mayflies, Canadian soldiers, shadflies, fishflies, up-winged flies
Mayflies (Ephemeroptera) represent the oldest known winged insects, with fossil evidence dating to approximately 350 million years ago in the lower Carboniferous. The order contains over 3,000 described species across more than 400 genera and 42 families worldwide. Adults are characterized by short lifespans—typically hours to days—and a unique subimaginal stage where the winged but sexually immature subimago undergoes a final molt to become a reproductive imago. Larvae are exclusively aquatic and serve as important indicators of water quality in freshwater ecosystems.
Ephydrinae
shore flies
Ephydrinae is a subfamily of shore flies within the family Ephydridae, first described by Zetterstedt in 1837. The subfamily contains four recognized tribes: Ephydrini, Scatellini, Parydrini, and Dagini. Members are commonly found in association with aquatic or semi-aquatic habitats. The group includes genera such as Ephydra, Scatella, and Parydra.
Eucorethra
phantom midges
Eucorethra is a monotypic genus of phantom midges in the family Chaoboridae, containing the single species Eucorethra underwoodi. This genus belongs to a family of non-biting midges known for their distinctive aquatic larvae. The genus was established by Underwood in 1903.
Euparyphus
Euparyphus is a genus of soldier flies (Diptera: Stratiomyidae) in the tribe Oxycerini. Species in this genus are associated with madicolous habitats—thin water films on rock surfaces—in eastern North America. The genus contains approximately 30 described species distributed across the Americas, with adults and immature stages described for several North American species.
Feuerborniella opposita
Feuerborniella opposita is a species of moth fly in the family Psychodidae, first described by Nathan Banks in 1901. The genus Feuerborniella comprises small, delicate flies commonly associated with moist or aquatic environments. As a member of Psychodidae, it belongs to a diverse family of nematoceran Diptera with larvae typically found in wet habitats. The species is documented from a limited number of observations, suggesting it may be uncommon or underrecorded.
Gastrops
shore flies
Gastrops is a genus of shore flies in the family Ephydridae, established by Williston in 1897. The genus contains approximately eight described species distributed across the Neotropical and Nearctic regions. Members of this genus are associated with aquatic or semi-aquatic habitats typical of ephydrid flies.
Gerridae
water striders, water bugs, pond skaters, water skippers, Jesus bugs, water skeeters, water scooters, water gliders, water skimmers, puddle flies
Gerridae are a family of true bugs (Hemiptera: Heteroptera) renowned for their ability to walk on water. They possess hydrofuge hairpiles covering the body and specialized leg structures that exploit water surface tension. Most species inhabit freshwater, though the genus Halobates is exceptional as the only truly oceanic insect, living on open ocean surfaces. Over 1,700 species have been described, with body lengths ranging from 2–36 mm. They are predatory, feeding on surface-trapped invertebrates.
Goeridae
Armour-ballast Caddisflies
Goeridae is a family of caddisflies (Trichoptera) comprising approximately 12 genera and at least 160 described species. Larvae are primarily lotic, inhabiting streams and rivers, with some species occupying madicolous habitats such as wet cliff faces. The family is distinguished by larval case construction incorporating ballast stones for weight and stability. Adults exhibit highly modified male genitalia and maxillary palps in some species. Goeridae has a Holarctic distribution with records from North America, Europe, and Asia.
Greniera
Greniera is a genus of black flies in the family Simuliidae, established by Doby and David in 1959. The genus belongs to the tribe Prosimuliini and includes at least two described species: Greniera abdita and Greniera abditoides. Species are known from Europe and North America.
Guttipelopia
Guttipelopia is a genus of non-biting midges in the subfamily Tanypodinae, family Chironomidae. The genus is distinguished by distinctive wing pigmentation patterns featuring darkened areas (guttae) on the wing membrane. Taxonomic review has clarified species boundaries, confirming the conspecificity of Nearctic G. multipunctata and Palaearctic G. guttipennis, with G. currani synonymized under the latter. The genus contains three recognized species: G. guttipennis, G. currani, and G. rosenbergi.
Gymnochthebius
minute moss beetles
Gymnochthebius is a genus of minute moss beetles in the family Hydraenidae, containing more than 60 described species. The genus is particularly diverse in Australia and Papua New Guinea, where 36 species have been documented. These small water beetles inhabit marginal zones of aquatic habitats and show microhabitat specialization correlated with morphological adaptations.
Gymnomyzinae
shore flies
Gymnomyzinae is a subfamily of shore flies within the family Ephydridae. The subfamily comprises approximately seven genera and nine described species. Members are classified into five tribes: Discocerinini, Gastropini, Gymnomyzini, Hecamedini, and Lipochaetini, plus the unplaced tribe Ochtherini. The genus Ochthera, with approximately 37 described species, is the most species-rich and well-known group within this subfamily.
Habrophlebiodes
Habrophlebiodes is a genus of mayflies in the family Leptophlebiidae, established by Ulmer in 1920. The genus contains species distributed across Asia and the Americas, with at least four Asian species documented. Asian species include three endemics to China (H. gilliesi, H. tenella, H. zijinensis) plus H. prominens. The genus is divided into two distinct clades with morphological differences separating Asian and American species.
Helopicus
springflies
Helopicus is a genus of springflies (order Plecoptera) in the family Perlodidae, established by Ricker in 1952. The genus contains at least four described species distributed across eastern North America and parts of Asia. Species in this genus are part of the stonefly group Systellognatha, characterized by their predatory or omnivorous feeding habits as nymphs.
Hemerodromiini
Hemerodromiini is a tribe of dance flies (family Empididae) within the subfamily Empidinae. Members of this tribe are small to medium-sized predatory flies characterized by their distinctive leg structure and behavior. The tribe is distinguished from related groups by morphological adaptations associated with their characteristic hunting strategy. Hemerodromiini species are found across various habitats, particularly in association with running water and moist environments.
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.
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.
Heteroplectron
Heteroplectron is a genus of caddisflies in the family Calamoceratidae, established by McLachlan in 1871. The genus contains at least three described species: Heteroplectron americanum (eastern North America), Heteroplectron californicum (western North America), and Heteroplectron yamaguchii (East Asia). As members of the Calamoceratidae, species in this genus construct distinctive larval cases.
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.
Homoplectra
homoplectran caddisflies
Homoplectra is a genus of netspinning caddisflies in the family Hydropsychidae, established by Ross in 1938. The genus comprises approximately 11 described species distributed in North America and Japan. As members of Hydropsychidae, larvae construct fixed capture nets to filter food from flowing water. The genus includes the recently described species H. gracilis from Japanese headwater streams.
Hydrelliinae
Hydrelliinae is a subfamily of shore flies within the family Ephydridae, comprising approximately 10 genera and at least 130 described species. These small flies are primarily associated with aquatic and semi-aquatic environments. The subfamily is distinguished by ecological and morphological traits that separate it from other ephydrid groups. Members are found across multiple continents with varying habitat preferences.
Hydroporinae
Hydroporinae is a large subfamily of predaceous diving beetles (family Dytiscidae) containing at least 2,200 described species. Members are primarily aquatic, inhabiting diverse freshwater habitats from lentic pools to lotic streams across all continents except Antarctica. The subfamily exhibits remarkable diversity in body size, with some species among the smallest diving beetles known. Many species are habitat specialists, including stygobiont forms adapted to subterranean waters.
Hydroporini
Hydroporini is a tribe of predaceous diving beetles in the family Dytiscidae, containing at least 730 described species. Members are primarily aquatic, inhabiting freshwater environments including streams, rivers, and groundwater systems. The tribe exhibits a broad geographic distribution spanning Australia, New Guinea, Europe, and other regions, with notable diversity hotspots in south-western Australia.
Hydropsychidae
Net-spinning Caddisflies
Hydropsychidae, commonly known as net-spinning caddisflies, is a family of aquatic insects in the order Trichoptera. Larvae construct silk nets at the openings of their retreats to capture food particles from flowing water. The family is globally distributed in freshwater habitats and serves as important bioindicators of stream health. Larvae exhibit unique behaviors including territorial defense through stridulation and competitive interactions for retreat ownership.
Hydroptilidae
Microcaddisflies, Purse-case Caddisflies
Hydroptilidae is the largest family of caddisflies (Trichoptera), comprising over 2,600 species in 76 genera and six subfamilies. Adults are minute, rarely exceeding 5 mm in length, making them the smallest caddisflies. They are characterized by simple hypermetamorphosis in larvae: early instars (I–IV) are caseless and free-living, while the final instar (V) constructs a distinctive purse-shaped portable case and develops a greatly enlarged (physogastric) abdomen as the primary feeding and growing stage. The family has a worldwide distribution, with subfamilies showing distinct regional patterns. Adults are strongly attracted to ultraviolet lights and may congregate in large numbers.
Hyporhygma
Hyporhygma is a genus of non-biting midges (Chironomidae) described by Reiss in 1982. As a member of this large dipteran family, adults are characterized by reduced mouthparts and aquatic larval stages. The genus is part of the diverse chironomid fauna found in freshwater habitats worldwide.
Ilytheinae
shore flies
Ilytheinae is a subfamily of shore flies within the family Ephydridae (order Diptera). The subfamily comprises two tribes: Ilytheini and Hyadinini, containing approximately 12 genera including Donaceus, Ilythea, Hyadina, and Nostima. Members of this subfamily are associated with moist or aquatic habitats, consistent with the broader ecology of Ephydridae.
Ioscytus
Ioscytus is a genus of shore bugs in the family Saldidae, established by Reuter in 1912. The genus contains seven described species distributed in North America. These insects are associated with moist shoreline habitats. Members of this genus are part of the leptopodomorphan lineage within the true bugs.
Isonychiidae
Brush-legged Mayflies
Isonychiidae is a monogeneric family of mayflies containing the single extant genus Isonychia Eaton, 1871, with approximately 37 species distributed across the Holarctic and Oriental regions. The family is characterized by distinctive brush-like or hairy legs in the adult stage, giving rise to the common name "brush-legged mayflies." Species inhabit flowing water habitats, with nymphs occurring on rocky substrates in streams and creeks. The family is among the earliest reported groups of Chinese Ephemeroptera and is relatively abundant at suitable sampling sites.
Krenosmittia
Krenosmittia is a genus of non-biting midges in the family Chironomidae, subfamily Orthocladiinae. The genus contains approximately 20 described species. Larvae have been documented inhabiting the hyporheic zone—the saturated interstitial spaces beneath and alongside stream beds—rather than typical surface sediments. Species occur across parts of Europe, Asia, and Russia.
Labrundinia
Labrundinia is a genus of non-biting midges in the family Chironomidae, subfamily Tanypodinae. The genus was established by Fittkau in 1962 and is predominantly tropical in distribution, though its type species Labrundinia longipalpis exhibits an anomalous Holarctic range. Species in this genus are aquatic in their immature stages and belong to the bloodworm group of chironomids.
Leptocerus
long-horned caddisflies
Leptocerus is a genus of long-horned caddisflies in the family Leptoceridae, comprising more than 140 described species. Larvae construct species-specific protective cases. The genus includes species of conservation concern, such as the critically endangered Leptocerus interruptus.
Leptopodomorpha
shore bugs, spiny shore bugs
Leptopodomorpha is an infraorder of true bugs (Hemiptera: Heteroptera) comprising over 380 species across four families. The group is commonly known as shore bugs or spiny shore bugs due to their association with riparian and intertidal habitats. The family Saldidae dominates the infraorder with approximately 350 species and is notable for jumping ability. The remaining families—Leptopodidae, Omaniidae, and Aepophilidae—are considerably smaller, with Leptopodidae containing about 30 species and the latter two families being highly reduced.
Liancalus hydrophilus
Liancalus hydrophilus is a species of long-legged fly in the family Dolichopodidae, described by Aldrich in 1893. It belongs to a genus whose members are associated with aquatic and semi-aquatic habitats. Like other dolichopodids, adults are predatory on small insects. The species epithet 'hydrophilus' (water-loving) reflects its affinity for moist environments. Very few observations of this species have been documented.
Liancalus limbatus
Liancalus limbatus is a species of long-legged fly in the family Dolichopodidae, described by Van Duzee in 1917. The genus Liancalus belongs to the subfamily Hydrophorinae, a group associated with aquatic and semi-aquatic habitats. Like other dolichopodids, members of this genus are predatory as adults. The specific epithet "limbatus" refers to a bordered or edged characteristic, though the precise morphological basis for this name is not documented in available sources.
Libellulidae
skimmers, perchers, chasers, darters, meadowhawks
Libellulidae is the largest family of dragonflies, comprising over 1000 species with nearly worldwide distribution. Members are commonly known as skimmers, perchers, chasers, or darters. The family is characterized by broad, often flattened abdomens and a tendency to perch frequently. Many species display bright colors or banded wings. The family name derives from Latin "libella," meaning a carpenter's level, referencing the insect's ability to remain level when hovering. Larvae have stout bodies with the labium developed into a mask over the lower face. The earliest fossil record dates to the Late Cretaceous (Turonian) of Kazakhstan.
Limnellia
Limnellia is a genus of shore flies in the family Ephydridae, established by Malloch in 1925. These small dipterans are associated with aquatic or semi-aquatic environments. The genus has been recorded from northern European countries including Denmark, Norway, and Sweden. As with other ephydrid flies, species in this genus likely develop in moist habitats with organic matter.
Limnephiloidea
Limnephiloidea is a superfamily of caddisflies (Trichoptera) established by Kolenati in 1848. It encompasses several families of case-making caddisflies, including the diverse family Limnephilidae. Members of this superfamily are predominantly found in freshwater aquatic habitats during their larval stages.