Aquatic-insect
Guides
Abedus breviceps
water bug
Abedus breviceps is a giant water bug in the family Belostomatidae, characterized by exclusive paternal care behavior where males carry egg masses on their backs. Research using capture-recapture multistate modeling found no survival cost to males from brooding eggs, challenging assumptions about parental care trade-offs. The species inhabits aquatic environments in Middle and North America.
Abedus herberti
toe biter, ferocious water bug
Abedus herberti is a flightless giant water bug native to streams in the southwestern United States and northwestern Mexico. Adults measure 2–4 cm and are known for male parental care, where females attach eggs to the male's back and he carries them until hatching. The species is a sit-and-wait predator that captures prey with raptorial front legs and subdues it with venomous saliva. It has been documented in zoo displays and is consumed as food in some cultures, marketed as "Mexican caviar."
Abedus immaculatus
Abedus immaculatus is a species of giant water bug in the family Belostomatidae. It is the only Abedus species found in the eastern United States, with a range extending throughout Florida north into Georgia and west along the Gulf Coast to Mississippi. Adults measure 13–14 mm in length, making them the smallest species in the genus Abedus and the smallest belostomatid in the United States. The species is the sole member of the subgenus Microabedus. It is locally common in parts of the Everglades, where it occurs in shorter hydroperiod sites.
giant-water-bugaquatic-insectfreshwaterwetlandEvergladesendemiceastern-United-Statessmallest-belostomatid-USAmale-parental-careBelostomatidaeHemipteraMicroabedushydroperiodFloridaGeorgiaMississippiGulf-CoastThomas-Say1832Abedus-cantrallisynonymywater-bugtrue-bugNepomorphaHeteropteraInsectaArthropodaAnimaliaAblabesmyia annulata
Ablabesmyia annulata is a species of non-biting midge in the family Chironomidae, originally described by Thomas Say in 1823 as Tanypus annulata. The species occurs in the Nearctic region, with documented populations in Canadian freshwater lakes including Lake Winnipeg, Manitoba, and Marion Lake, British Columbia. Like other members of the genus, it has an aquatic larval stage with instar separation approximately following Dyar's rule. The immatures and males have been formally redescribed and illustrated in taxonomic literature.
Ablabesmyia cinctipes
Ablabesmyia cinctipes is a species of non-biting midge in the family Chironomidae, order Diptera. The species was described by Johannsen in 1946. Chironomidae is a large family of aquatic insects whose larvae inhabit diverse freshwater environments. Adults are generally short-lived and do not feed.
Ablabesmyia mallochi
Ablabesmyia mallochi is a non-biting midge species in the family Chironomidae. The immature stages and males were redescribed and illustrated in a 2011 revision of Canadian Ablabesmyia. It belongs to the subgenus Ablabesmyia (Ablabesmyia).
Acentrella turbida
Acentrella turbida is a small minnow mayfly in the family Baetidae, first described by McDunnough in 1924. It is one of the most widespread mayfly species in North America, occurring across the continent from Alaska and Canada through the continental United States to northern Mexico, with additional populations in Central America. The species was originally described under the genus Pseudocloeon before being transferred to Acentrella. It belongs to a diverse genus containing numerous small, delicate mayfly species often difficult to distinguish without close examination.
Acentria
watermilfoil moth, water veneer
Acentria is a monotypic moth genus in the family Crambidae containing a single species, Acentria ephemerella. The genus is notable for extreme sexual dimorphism in wing development and for having the only known fully aquatic adult female moths. Most females are flightless with rudimentary wings and spend their entire lives underwater, while males are fully winged and terrestrial. The species is native to Europe and has been introduced to North America.
Acerpenna macdunnoughi
small minnow mayfly
Acerpenna macdunnoughi is a species of small minnow mayfly in the family Baetidae. Originally described as Baetis macdunnoughi by Ide in 1937, it was later transferred to the genus Acerpenna. The species is found in North America.
Acroneuria abnormis
Common Stone
Acroneuria abnormis, commonly known as the common stone, is a species of stonefly in the family Perlidae. It is widely distributed across North America. The species is notable for its drumming behavior during mating, which produces species-specific vibrational signals used for identification and mate recognition.
Acroneuria arenosa
Eastern Stone
Acroneuria arenosa, commonly known as the eastern stone, is a species of common stonefly in the family Perlidae. It was first described by Pictet in 1841 under the basionym Perla arenosa. This species belongs to the order Plecoptera and is part of the diverse stonefly fauna of North America. Stoneflies in the genus Acroneuria are generally considered predatory and are indicators of good water quality.
Acroneuria carolinensis
Carolina Stone
Acroneuria carolinensis, commonly known as the Carolina stone, is a predatory stonefly in the family Perlidae. It has a univoltine life cycle with emergence from late May through mid-July. Nymphs undergo an ontogenetic habitat shift, moving from leaf packs in slow water as small instars to cobble substrates in riffles as they grow larger. Adults are short-lived, do not feed, and are attracted to lights. The species functions as a top invertebrate predator in stream ecosystems.
Acroneuria evoluta
Constricted Stone
Acroneuria evoluta, commonly known as the constricted stone, is a species of stonefly in the family Perlidae. The species was described by Klapálek in 1909. It is distributed across parts of the eastern and central United States.
Acroneuriinae
Acroneuriinae is a subfamily of stoneflies within the family Perlidae, comprising approximately 32 genera and 520 described species. Members are aquatic insects whose larvae inhabit freshwater environments. The subfamily has been the subject of recent mitogenomic research, including the first documented gene rearrangements in the order Plecoptera.
Adicrophleps
Adicrophleps is a monotypic genus of caddisflies in the family Brachycentridae, established by Flint in 1965. The genus contains a single described species, A. hitchcocki. Members are classified as "humpless casemaker" caddisflies, distinguishing them from the "humped" Brachycentrinae subfamily.
Agabetes
Agabetes is a small genus of diving beetles (family Dytiscidae) in the subfamily Laccophilinae. The genus contains two described species: Agabetes acuductus, described from North America in 1828, and Agabetes svetlanae, described from the Palearctic region in 1989. The genus is the type genus of the tribe Agabetini. Members are aquatic beetles inhabiting freshwater environments.
Agabus arcticus
Agabus arcticus is a predaceous diving beetle in the family Dytiscidae with a Holarctic distribution, occurring in North America and the Palearctic region. It belongs to the arcticus-group of Agabus species, which is characterized by specific morphological and ecological traits adapted to northern environments. The species has three described larval stages and is known from reared material collected in northern Sweden.
Agapetus rossi
little black caddisfly
Agapetus rossi is a species of little black caddisfly in the family Glossosomatidae, first described by Denning in 1941. It is found in North America. Like other members of its family, it is a small, dark-colored caddisfly. The Glossosomatidae family, commonly known as saddle-case makers, are characterized by their distinctive larval cases.
Agathon comstocki
Comstock's Net-winged Midge
Agathon comstocki is a species of net-winged midge in the family Blephariceridae, described by Kellogg in 1903. The common name honors the American entomologist John Henry Comstock. Net-winged midges in this family are specialized for life in fast-flowing aquatic environments, with larvae adapted to cling to rocks in turbulent water. The species is rarely encountered and poorly documented in scientific literature.
Agnetina annulipes
southern stone
Agnetina annulipes, commonly known as the southern stone, is a species of stonefly in the family Perlidae. It is one of the larger stonefly species in eastern North America. The species was originally described as Perla annulipes by Hagen in 1861 before being transferred to the genus Agnetina. It is primarily found in the southeastern United States.
Agnetina capitata
Northern Stone
Agnetina capitata, commonly known as the northern stone, is a species of stonefly in the family Perlidae. It occurs in North America, with records from eastern Canada and multiple U.S. states including Arkansas, Connecticut, Delaware, and Illinois. As a member of the order Plecoptera, it is associated with aquatic habitats during its immature stages. The species was originally described as Perla capitata by Pictet in 1841.
Agnetina flavescens
Midwestern Stone
Agnetina flavescens, commonly known as the midwestern stone, is a stonefly species in the family Perlidae. It is native to North America and has been documented in several midwestern and southeastern US states. As a member of the common stoneflies, it inhabits freshwater systems where its aquatic nymphs develop. The species was originally described as Perla flavescens by Walsh in 1862 before being transferred to the genus Agnetina.
Allocapnia maria
Two-knobbed Snowfly
Allocapnia maria, the two-knobbed snowfly, is a small winter stonefly in the family Capniidae. The species was described by Hanson in 1942 and occurs in eastern North America. Like other winter stoneflies, it is active during cold months when most other insects are dormant.
Allocapnia rickeri
Midwest Snowfly
Allocapnia rickeri is a small winter stonefly in the family Capniidae, commonly known as the Midwest Snowfly. It is one of numerous small, dark stoneflies in the genus Allocapnia that emerge during cold months when few other insects are active. The species has been documented across the central and eastern United States. Like other capniids, it is associated with clean, cold streams and is an important indicator of water quality.
winter-stoneflybioindicatorcoldwaterPlecopteraCapniidaeAllocapnialoticemergencebrachypteryapterygenitalia-identificationFrison-1942Midwestsoutheastern-USclean-water-indicatorJanuary-Marchsmall-stoneflywingless-femalestream-insectshreddergathererseasonal-resourcewater-qualityaquatic-insectterrestrial-adultshort-lived-adultovipositionsubmerged-eggshigh-dissolved-oxygenlow-temperaturecentral-USeastern-USAlabamaArkansasDelawareGeorgiaIllinoishexapodhemimetabolousEuholognathaNemouroideaArctoperlariaInsectaArthropodaAnimaliaGBIFCatalogue-of-LifeiNaturalistNCBItaxonomyaccepted-species1942FrisonRickerMidwest-Snowflysnowflysmall-dark-stoneflyclean-streamsriverswell-oxygenatedlotic-habitatcold-monthswinter-activitywing-reductionfemale-apterymale-flightepiproctparaproctterminaliataxonomic-revisioncongenersdistribution-recordsobservations9-observationseukaryotemetazoanarthropodinsectstoneflywinter-emergingJanuaryFebruaryMarchcold-weathernear-freezingbelow-freezingwater-surfacesubmerged-substratesallochthonous-organic-materialstream-ecosystemsseasonal-food-resourceinsectivorous-birdspredatorsscarce-preyunpollutedno-economic-importancestream-monitoringwater-quality-indicatorhigh-quality-coldwatermicroscopic-examinationtaxonomic-keysmale-terminaliareliable-separationgenitalic-examinationoverlapping-distributionsimilar-habitatsmall-sizeunder-10-mmbody-lengthreduced-wingsabsent-wingsfully-developed-wingsspecific-identificationpublished-descriptionsillustrationssubsequent-revisionscharacteristicfamily-Capniidaecommon-nameextended-nymphal-periodone-to-two-yearsshort-liveddoes-not-feedaquatic-nymphclean-cold-streamslow-temperaturesyear-roundwinter-monthsJanuary-through-Marchfamilycentered-Midwestextends-southeasternUnited-Statesdocumentedappearsmost-reliablydistinguishedsubtle-differencesterminal-abdominal-structuresshould-be-comparedagainstpublishedsubsequentgenus-levelcharacterizedreducedabsentfemalesfully-developedmalesrequires-examinationmale-genitaliastructureparaproctsreliableseparationoverlapssimilarmanyexternallydefinitivereliesmicroscopicexaminationcomparisonkeysusedbiologicalindicatorprogramspresenceindicatescoldconditionsno-directeconomicimportanceshreddersgatherersprocessingallochthonousorganicmaterialstreamecosystemsseasonalfoodresourceinsectivorousbirdsotherwhenalternativepreyscarceserveshigh-qualityhabitatsdevelopmentaquaticnymphalstagesterrestrialadultstagenymphsdevelopstreamsextendedperiodlikelyonetwoyearsbasedrelatedspeciesadultsdo-notfeedactiveduringweatherairtemperaturesmaynearbelowfreezingwingedcapableflightwinglessshort-wingedremainwatersurfacematingoccurwinterenteringdepositeggssubmergedsubstratessmallcommonlyknownnumerousdarkemergefewinsectscentraleasternassociatedcleanimportantundermmbodylengthmembersgenuswingspossessfullydevelopedspecificidentificationlevelwithinrequiresmalegenitaliaparticularlymostreliablysubtledifferencestheseterminalabdominalstructuresshouldcompareddescriptionstaxonomicrevisionswinter-emergingmaintainlowhighdissolvedoxygenlevelsthroughoutyearUnitedStatesdistributioncenteredextendssoutheasternmonthstypicallythroughthisactivitygivesrisecommonnamedonotprovidesqualitymonitoringnodirecthabitatmorphologysizegenitalicAlloperla concolor
Duckhead Sallfly
Alloperla concolor, commonly known as the duckhead sallfly, is a species of green stonefly in the family Chloroperlidae. It was described by Ricker in 1936 and is native to North America. The species belongs to a family whose members are typically predatory as nymphs and are indicators of clean, well-oxygenated aquatic environments.
Alluaudomyia paraspina
Alluaudomyia paraspina is a species of predaceous midge in the family Ceratopogonidae, described by Wirth in 1952. The immature stages (larvae and pupae) develop in aquatic habitats rich in decaying organic matter. As a member of the genus Alluaudomyia, it is presumed to be predatory in both larval and adult stages, though specific prey records remain limited.
Alotanypus venustus
Alotanypus venustus is a species of non-biting midge in the family Chironomidae, subfamily Tanypodinae. It was originally described as Tanypus venustus by Coquillett in 1902 and later transferred to the genus Alotanypus. The species is part of the tribe Pentaneurini, a group of predatory midges whose larvae inhabit aquatic environments. As a member of Chironomidae, it is distinguished from biting midges (Ceratopogonidae) such as Culicoides species, with which it shares no close relationship despite superficial similarities in common name usage.
Ambrysus arizonus
Ambrysus arizonus is a creeping water bug (family Naucoridae) in the Ambrysus guttatipennis species complex. It is distributed in both the United States and Mexico, with recent records extending its known range into Mexico. As a member of the Cryphocricinae subfamily, it shares the characteristic saucer-like, flattened body form and aquatic lifestyle typical of this group.
Ambrysus mormon
creeping water bug
Ambrysus mormon is a species of creeping water bug in the family Naucoridae, first described by Montandon in 1909. Three former subspecies (A. m. heidemanni, A. m. minor, and A. m. mormon) were synonymized by Reynoso-Velasco and Sites. The species is distributed in western North America, with records from the western United States and northwestern Mexico.
Ambrysus occidentalis
Ambrysus occidentalis is a species of creeping water bug in the family Naucoridae, described by La Rivers in 1951. It is distributed across Central America and North America. As a member of Naucoridae, it is an aquatic true bug adapted to life in freshwater environments. A study on its mating behavior has been published in the American Midland Naturalist, indicating research interest in its reproductive biology.
Ambrysus pulchellus
Ambrysus pulchellus is a creeping water bug in the family Naucoridae, part of the A. pulchellus species complex characterized by distinctive male phallosoma morphology and medial lobes of abdominal tergum VIII. The species exhibits the widest distribution within the subgenus Ambrysus, spanning parts of both the Nearctic and Neotropical biogeographic realms. Recent taxonomic revision has synonymized the subspecies A. pulchellus nitidulus and A. pulchellus pallidulus with the nominate form, and documented new country records from Honduras, Nicaragua, and Panama.
Ameletidae
combmouthed minnow mayflies
Ameletidae is a family of mayflies commonly known as combmouthed minnow mayflies. The family includes the speciose genus Ameletus, which reaches its greatest diversity in southwestern North America with up to 12 species co-occurring at single sites. The genus Metreletus has a trans-Palaearctic distribution with three recognized species. Ameletidae larvae are aquatic and occur in lotic habitats from small headwater streams to larger rivers.
Ameletus browni
purple marram
Ameletus browni is a mayfly species in the family Ameletidae, commonly known as the "purple marram." It was described by McDunnough in 1933 based on nymphal specimens collected in southern British Columbia. The species belongs to the Nearctic fauna and is found in northeastern North America, including Canada and the northeastern United States. Like other members of the genus Ameletus, it is associated with cool, clean freshwater habitats.
Ameletus celer
Ameletus celer is a Nearctic species of mayfly in the family Ameletidae, described by McDunnough in 1934. As a member of the genus Ameletus, it belongs to a group of mayflies commonly known as the "prong-gilled mayflies" due to the distinctive forked structure of their gills. The species occurs in North America, though specific ecological details remain poorly documented in the available literature.
Ameletus ludens
Ameletus ludens is a species of combmouthed minnow mayfly in the family Ameletidae, described by Needham in 1905. It belongs to the order Ephemeroptera, a group of aquatic insects known for their brief adult lifespans. The species is found in North America, though specific details about its ecology and life history remain limited in available sources.
Ameletus similior
Ameletus similior is a mayfly species (Ephemeroptera: Ameletidae) described by McDunnough in 1928. It occurs in western North America from southern British Columbia to Alberta, with identification keys also applicable to Saskatchewan, Montana, and northern Idaho and Washington. The species was previously known as A. monta, which has been synonymized with A. similior. Adult males have practically clear hyaline wings and differ from the similar A. alticolus in genitalic characters.
Amiocentrus
humpless casemaker caddisflies
Amiocentrus is a genus of caddisflies (order Trichoptera) in the family Brachycentridae, commonly referred to as humpless casemaker caddisflies. The genus was established by Ross in 1938 and contains at least two described species: Amiocentrus aspilus and Amiocentrus tessellatum. Members of this genus are aquatic insects whose larvae construct portable cases from plant material.
Amphinemura wui
spiked forestfly
Amphinemura wui, commonly known as the spiked forestfly, is a species of spring stonefly in the family Nemouridae. It is a small, non-venomous insect belonging to the order Plecoptera. The species was described by Claassen in 1936. It is found in North America, with records from several eastern and southeastern U.S. states.
Amynothrips andersoni
Alligatorweed Thrips, Alligator Weed Thrips
Amynothrips andersoni is a species of thrips in the family Phlaeothripidae, native to South America and introduced to the United States as a biological control agent against the invasive aquatic weed alligator weed (Alternanthera philoxeroides). Adults are small, shiny black insects approximately 2 mm in length. The species exhibits wing dimorphism, with both short-winged and long-winged flying forms present, though the latter is rare. Both larval and adult stages feed on alligator weed, causing leaf curling and plant stunting.
Anafroptilum bifurcatum
Anafroptilum bifurcatum is a species of small mayfly in the family Baetidae, first described by McDunnough in 1924. The genus Anafroptilum was established to accommodate certain Baetidae species previously placed in other genera, distinguished by specific morphological features of the genitalia and wing venation. As a member of the Baetidae, it belongs to a diverse family of small, agile mayflies commonly known as blue-winged olives or small minnow mayflies.
Anafroptilum conturbatum
Anafroptilum conturbatum is a species of small mayfly in the family Baetidae. As a member of this diverse family, it inhabits freshwater environments where it contributes to aquatic food webs. The species was described by McCafferty and Waltz in 1995. Like other baetid mayflies, it likely has a short adult lifespan focused primarily on reproduction.
Anafroptilum minor
Anafroptilum minor is a species of small minnow mayfly in the family Baetidae. Like other members of this family, it is characterized by reduced wing venation and relatively simple morphology compared to other mayfly families. The genus Anafroptilum contains species that are typically associated with running water habitats. Specific ecological details for A. minor are limited in available literature.
Anagapetus
little black caddisflies
Anagapetus is a genus of small caddisflies in the family Glossosomatidae, commonly called little black caddisflies. The genus contains approximately seven described species. Members of this genus are part of the case-making caddisfly family Glossosomatidae, whose larvae construct portable cases from mineral grains.
Ancyronyx variegata
Spider Water Beetle
Ancyronyx variegata is a riffle beetle (Elmidae) commonly known as a Spider Water Beetle, characterized by extremely long legs and often a cross-like elytral color pattern that gives it a spider-like appearance. It inhabits clean, pristine running waters in lotic environments and has been studied for its life history and energetics in Northwest Arkansas and Southeast Texas. The species exhibits a univoltine life cycle with adults present year-round.
Anisoptera
Dragonflies
Anisoptera is the suborder of dragonflies, distinguished from damselflies (Zygoptera) by their larger, stouter bodies, eyes that touch or nearly touch at the top of the head, and wings held horizontally away from the body at rest. The name derives from Greek roots meaning 'unequal wings,' referring to the broader hindwings compared to forewings. With over 3,000 described species globally, dragonflies represent one of the most ancient lineages of flying insects, with fossil relatives dating to the Triassic Period 250 million years ago. Adults are aerial predators with exceptional flight capabilities and vision, while larvae are aquatic predators found in diverse freshwater habitats.
Anthopotamus distinctus
Golden Drake, hacklegilled burrower mayfly
Anthopotamus distinctus is a species of mayfly in the family Potamanthidae, commonly known as the Golden Drake. It belongs to a group referred to as hacklegilled burrower mayflies, indicating specialized gill structures and burrowing behavior in the nymphal stage. The species is found in the Nearctic region of eastern North America.
Apatania incerta
early smoky wing sedge
Apatania incerta is a species of caddisfly in the family Apataniidae, commonly referred to as the early smoky wing sedge. The species was originally described by Nathan Banks in 1897 under the basionym Enoicyla incerta. It is distributed across North America. As a member of the order Trichoptera, it possesses aquatic larval stages and terrestrial adults.
Arctocorisa sutilis
Arctocorisa sutilis is a species of water boatman in the family Corixidae, first described by Uhler in 1876. It belongs to a genus of aquatic true bugs found in freshwater habitats. The species is recorded from North America, particularly in the Nearctic region excluding Beringia. Like other corixids, it is an aquatic insect adapted to life in ponds, lakes, and slow-moving waters. Very limited published information exists on its specific biology.
Arctopsyche grandis
netspinning caddisfly
Arctopsyche grandis is a species of netspinning caddisfly in the family Hydropsychidae, found in North America. Larvae construct silk nets to capture food in flowing water and complete their development in approximately one year. The species has been studied in Central Idaho streams where it reaches high population densities on rocky substrates.
Argia funebris
Springwater Dancer
Argia funebris, commonly known as the Springwater Dancer, is a species of damselfly in the family Coenagrionidae. The genus Argia is speciose and widely distributed in the New World tropics and subtropics. As a member of the suborder Zygoptera, this species exhibits the characteristic slender body and wings folded together over the abdomen when at rest. The species has been documented across Middle America and has a global presence according to distribution records. Taxonomic revisions of the genus Argia have been conducted by leading odonate specialists including Rosser Garrison, who has published multiple revisions of this complex genus.