Editing Mayfly

{{Short description|Aquatic insects of the order Ephemeroptera}}
{{Other uses}}
{{Featured article}}
{{Use British English|date=August 2015}}
{{Automatic taxobox
| fossil_range = {{Fossil range|Late Carboniferous|Present|Late Carboniferous–present<ref name=IIBD>{{cite book |last1=Hoell |first1=H. V. |last2=Doyen |first2=J. T. |last3=Purcell |first3=A. H. |year=1998 |title=Introduction to Insect Biology and Diversity |edition=2nd |publisher=[[Oxford University Press]] |pages=320, 345–348 |isbn=978-0-19-510033-4}}</ref>}}
| image = Rhithrogena germanica subimago on Equisetum hyemale.jpg
| image_caption = ''[[Rhithrogena germanica]]'', the [[fly fisherman]]'s "March brown mayfly"
| display_parents = 3
| parent_authority = [[Rohdendorf]], 1968
| taxon = Ephemeroptera
| authority = [[Alpheus Hyatt|Hyatt]] & [[Jennie Maria Arms Sheldon|Arms]], 1890
| subdivision_ranks = Suborders and families
| subdivision = [[#Taxonomy and phylogeny|See text]]
}}

'''Mayflies''' (also known as  '''shadflies''' or fishflies<!--boldface is only for things that redirect here--> in Canada and the upper [[Midwestern United States]], as Canadian soldiers in the American [[Great Lakes region]],<ref>{{cite web |last=Galbincea |first=Barb |title=Canadian soldiers invade Rocky River (photo gallery) |url=https://www.cleveland.com/rocky-river/2014/06/canadian_soldiers_invade_rocky.html |website=cleveland.com |date=18 June 2014 |access-date=11 October 2022}}</ref> and as up-winged flies in the United Kingdom) are [[aquatic insect]]s belonging to the [[order (biology)|order]] '''Ephemeroptera'''. This order is part of an ancient group of insects termed the [[Palaeoptera]], which also contains [[dragonflies]] and [[damselflies]]. Over 3,000 [[species]] of mayfly are known worldwide, grouped into over 400 [[genera]] in 42 [[family (biology)|families]].

Mayflies have ancestral traits that were probably present in the first flying insects, such as long tails and [[Insect wing|wing]]s that do not fold flat over the [[insect morphology#Abdomen|abdomen]]. Their immature stages are aquatic [[fresh water]] forms (called "naiads" or "[[nymph (biology)|nymphs]]"), whose presence indicates a clean, unpolluted and highly oxygenated aquatic environment. They are unique among insect orders in having a fully winged terrestrial preadult stage, the subimago, which [[moulting|moults]] into a sexually mature adult, the [[imago]].

Mayflies "hatch" (emerge as adults) from spring to autumn, not necessarily in May, in enormous numbers. Some hatches attract tourists. [[Fly fishermen]] make use of mayfly hatches by choosing [[artificial fly|artificial fishing flies]] that resemble them. One of the most famous English mayflies is ''[[Rhithrogena germanica]]'', the fisherman's "March brown mayfly".<ref name=McCully/>

The brief lives of mayfly adults have been noted by naturalists and encyclopaedists since [[Aristotle]] and [[Pliny the Elder]] in [[classical antiquity]]. The German engraver [[Albrecht Dürer]] included a mayfly in his 1495 engraving ''[[The Holy Family with the Mayfly]]'' to suggest a link between heaven and earth. The English poet [[George Crabbe]] compared the brief life of a daily newspaper with that of a mayfly in the satirical poem "The Newspaper" (1785), both being known as "ephemera".

== Description ==

=== Nymph ===

{{multiple image|perrow=2/1|total_width=330|caption_align=center
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| image1 = Mayfly nymph dorsal view wing buds paired gills.JPG
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| image2 = Leptophlebia.marginata.subimago.jpg
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| image3 = Mayfly instar.jpg
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| image4 = Eendagsvlieg (257301115).jpeg
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| footer = {{font|size=100%|font=Sans-serif|text=Top left: Mayfly nymph, dorsal view, showing the paired gills and three projections on the abdomen; wing buds are visible on the thorax. Top right: Subimago of ''[[Leptophlebia marginata]]''. Middle: Nymph of the mayfly ''[[Cloeon dipterum]]'', showing seven pairs of [[gill]]s along the sides of the abdomen. Bottom: Lateral view of mayfly [[Insect wing|wing]] translucent [[Iridescence#Examples|iridescence]].}}
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Immature mayflies are [[aquatic insect|aquatic]] and are referred to as nymphs or naiads. In contrast to their short lives as adults, they may live for several years in the water. They have an elongated, cylindrical or somewhat flattened body that passes through a number of [[instar]]s (stages), moulting and increasing in size each time. When ready to emerge from the water, nymphs vary in length, depending on species, from {{convert|3|to|30|mm|2|abbr=on}}.<ref name=McCafferty1983/> The [[insect morphology#Head|head]] has a tough outer covering of [[sclerotin]], often with various hard ridges and projections; it points either forwards or downwards, with the mouth at the front. There are two large [[arthropod eye|compound eyes]], three [[ocelli]] (simple eyes) and a pair of [[antenna (biology)|antennae]] of variable lengths, set between or in front of the eyes. The mouthparts are designed for chewing and consist of a flap-like [[labrum (arthropod mouthpart)|labrum]], a pair of strong [[mandible (insect mouthpart)|mandibles]], a pair of [[maxilla (arthropod mouthpart)|maxillae]], a membranous [[Insect mouthparts#Hypopharynx|hypopharynx]] and a [[labium (insect)|labium]].<ref name=Dominguez/>

The [[Insect morphology#Thorax|thorax]] consists of three segments – the hindmost two, the [[mesothorax]] and [[metathorax]], being fused. Each segment bears a pair of legs which usually terminate in a single claw. The legs are robust and often clad in bristles, hairs or spines. Wing pads develop on the mesothorax, and in some species, hindwing pads develop on the metathorax.<ref name=Dominguez/>

The [[Insect morphology#Abdomen|abdomen]] consists of ten segments, some of which may be obscured by a large pair of [[operculum (animal)|operculate]] gills, a thoracic shield (expanded part of the [[prothorax]]) or the developing wing pads. In most [[taxa]] up to seven pairs of [[gill]]s arise from the top or sides of the abdomen, but in some species they are under the abdomen, and in a very few species the gills are instead located on the [[arthropod leg|coxae]] of the legs, or the bases of the maxillae. The abdomen terminates in slender thread-like projections, consisting of a pair of [[Cercus|cerci]], with or without a third central [[caudal filament]].<!--<ref>Imms, A. D., rev. Richards, O. W. & Davies, R. G. (1970) ''A General Textbook of Entomology'' 9th Ed. Methuen 886 pp.</ref>{{Page needed}}--><ref name=Dominguez>{{cite book |last=Domínguez |first=Eduardo |title=Ephemeroptera de América Del Sur |url=https://books.google.com/books?id=dwaJWle8OfkC&pg=PA17 |year=2006 |publisher=[[Pensoft Publishers]] |isbn=978-954-642-259-0 |pages=17–24 }}</ref>

===Subimago===
{{Anchor|Subimago}}<!-- [[Subimago]] redirects here -->

The final moult of the nymph is not to the full adult form, but to a winged stage called a subimago that physically resembles the adult, but which is usually sexually immature and duller in colour. The subimago, or dun,<ref>{{cite news|title=Subimago | work=Britannica.com}}</ref> often has partially cloudy wings fringed with minute hairs known as microtrichia; its eyes, legs and [[Insect reproductive system|genitalia]] are not fully developed. Females of some mayflies (subfamily Palingeniinae) do not moult from a subimago state into an adult stage and are sexually mature while appearing like a subimago with microtrichia on the wing membrane. Oligoneuriine mayflies form another exception in retaining microtrichia on their wings but not on their bodies. Subimagos are generally poor fliers, have shorter appendages, and typically lack the colour patterns used to attract mates. In males of ''[[Ephoron leukon]]'', the subimagos have forelegs that are short and compressed, with accordion like folds, and expands to more than double its length after moulting.<ref>{{Cite journal |last1=Edmunds |first1=George F. |author1-link=George F. Edmunds (entomologist) |last2=McCafferty |first2=W. P. |date=1988 |title=The Mayfly Subimago |journal=Annual Review of Entomology |volume=33 |issue=1 |pages=509–527 |doi=10.1146/annurev.en.33.010188.002453 |issn=0066-4170}}</ref> After a period, usually lasting one or two days but in some species only a few minutes, the subimago moults to the full adult form, making mayflies the only insects where a winged form undergoes a further moult.<ref name=McCafferty1983>{{cite book |last=McCafferty |first=W. Patrick |title=Aquatic Entomology: The Fishermen's and Ecologists' Illustrated Guide to Insects and Their Relatives |chapter-url=https://books.google.com/books?id=wiTq7x-fI_0C&pg=PA94 |year=1983 |publisher=[[Jones & Bartlett Learning|Jones & Bartlett]] |isbn=978-0-86720-017-1 |pages=91–123 |chapter=Mayflies}}</ref>

=== Imago ===

[[File:Mayfly - atalophlebia.jpg|thumb|upright|Adult ''[[Atalophlebia]]'' with the cylindrical dorsal or turban eyes visible]]

Adult mayflies, or [[imago]]s, are relatively primitive in structure, exhibiting traits that were probably present in the first flying insects. These include long tails and wings that do not fold flat over the abdomen.<ref>{{cite journal |last1=Thomas |first1=Jessica A. |last2=Trueman |first2=John W. H. |last3=Rambaut |first3=Andrew |last4=Welch |first4=John J. |year=2013 |title=Relaxed phylogenetics and the Palaeoptera problem: resolving deep ancestral splits in the insect phylogeny |journal=Systematic Biology |volume=62 |issue=2 |pages=285–297 |pmid=23220768 |doi=10.1093/sysbio/sys093 |doi-access=free }}</ref> Mayflies are delicate-looking insects with one or two pairs of membranous, triangular wings, which are extensively covered with [[Insect wing#Venation|veins]]. At rest, the wings are held upright, like those of a [[butterfly]]. The hind wings are much smaller than the forewings and may be [[vestigial]] or absent. The second segment of the [[thorax (insect anatomy)|thorax]], which bears the forewings, is enlarged to hold the main flight muscles. Adults have short, flexible antennae, large compound eyes, three ocelli and non-functional mouthparts. In most species, the males' eyes are large and the front legs unusually long, for use in locating and grasping females during the mid-air mating. In the males of some families, there are two large cylindrical "turban" eyes (also known as ''turbanate'' or ''turbinate'' eyes) that face upwards in addition to the lateral eyes.<ref>{{cite journal |last=Burghause |first=Frank |title=The structure of the double eyes of Baetis and the uniform eyes of Ecdyonurus (Ephemeroptera) |journal=Zoomorphology |year=1981 |volume=98 | pages=17–34 |doi=10.1007/BF00310318 |s2cid=36002849 }}</ref> They are capable of detecting ultraviolet light and are thought to be used during courtship to detect females flying above them.<ref name=polarized>{{cite book |last1=Horváth |first1=Gábor |last2=Varju |first2=Dezsö |title=Polarized Light in Animal Vision: Polarization Patterns in Nature |publisher=[[Springer Nature|Springer]] |year=2004 |pages=238–239}}</ref> In some species all the legs are functionless, apart from the front pair in males. The abdomen is long and roughly cylindrical, with ten segments and two or three long [[Cercus|cerci]] (tail-like appendages) at the tip. Like [[Entognatha]], [[Archaeognatha]] and [[Zygentoma]], the [[Spiracle (arthropods)|spiracles]] on the abdomen do not have closing muscles.<ref>[https://palivec.entu.cas.cz/~cizek/prednasky%20-%20JU/SystEnt12/Beutel2014-Insect-morphology.pdf Insect Morphology and Phylogeny (page 101)]</ref><ref>[https://www.zobodat.at/pdf/Ent-Abhandlungen-Dresden_61_0119-0172.pdf Proceedings of the 1st Dresden Meeting on Insect Phylogeny: "Phylogenetic Relationships within the Insect Orders". (Dresden, September 19-21, 2003) (page 7)]</ref> Uniquely among insects, mayflies possess paired genitalia, with the male having two [[aedeagi]] (penis-like organs) and the female two [[gonopore]]s (sexual openings).<ref name=IIBD/><ref name=McCafferty1983/>

== Biology ==

=== Reproduction and life cycle ===

Mayflies are [[hemimetabolous]] (they have "incomplete [[metamorphosis]]"). They are unique among insects in that they moult one more time after acquiring functional wings;<ref name=Lancaster>{{cite book |last1=Lancaster |first1=Jill |last2=Downes |first2=Barbara J. |title=Aquatic Entomology |url=https://books.google.com/books?id=QEYXWiobfcIC&pg=PA10 |year=2013 |publisher=[[Oxford University Press]] |isbn=978-0-19-957322-6 |pages=9–10}}</ref> this last-but-one winged ([[alate]]) instar usually lives a very short time and is known as a subimago, or to fly fishermen as a dun. Mayflies at the subimago stage are a favourite food of many fish, and many [[fishing flies]] are modelled to resemble them. The subimago stage does not survive for long, rarely for more than 24 hours. In some species, it may last for just a few minutes, while the mayflies in the family [[Palingeniidae]] have sexually mature subimagos and no true adult form at all.<ref name=IIBD/>

Often, all the individuals in a population mature at once (a hatch), and for a day or two in the spring or autumn, mayflies are extremely abundant, dancing around each other in large groups, or resting on every available surface.<ref name=McCafferty1983/> In many species the emergence is synchronised with dawn or dusk, and light intensity seems to be an important cue for emergence, but other factors may also be involved. ''[[Baetis intercalaris]]'', for example, usually emerges just after sunset in July and August, but in one year, a large hatch was observed at midday in June. The soft-bodied subimagos are very attractive to predators. Synchronous emergence is probably an [[antipredator adaptation|adaptive strategy]] that reduces the individual's [[Predator satiation|risk of being eaten]].<ref name=Flannagan>{{cite book |last1=Flannagan |first1=John F. |last2=Marshall |first2=K. Eric |title=Advances in Ephemeroptera Biology |url=https://books.google.com/books?id=XQ3pBwAAQBAJ&pg=PA293 |year=2012 |publisher=[[Springer Science+Business Media|Springer Science & Business Media]] |isbn=978-1-4613-3066-0 |page=293 }}</ref> The lifespan of an adult mayfly is very short, varying with the species. The primary function of the adult is reproduction; adults do not feed and have only vestigial [[Insect mouthparts|mouthparts]], while their digestive systems are filled with air.<ref name=Lancaster/> ''[[Dolania americana]]'' has the shortest adult lifespan of any mayfly: the adult females of the species live for less than five minutes.<ref name="entn_Chap">{{cite web |last=Welch |first=Craig H. |title=Chapter 37: Shortest Reproductive Life |work=Book of Insect Records |publisher=[[University of Florida]] |year=1998 |url=http://entnemdept.ifas.ufl.edu/walker/ufbir/chapters/chapter_37.shtml  |archive-url=https://web.archive.org/web/20150730141612/http://entnemdept.ifas.ufl.edu/walker/ufbir/chapters/chapter_37.shtml |archive-date=2015-07-30 }}</ref>

[[File:Shadfly01.jpg|thumb|Mayflies (known locally as shadflies) swarm briefly in enormous numbers in [[Ontario]].]]

Male adults may patrol individually, but most congregate in swarms a few metres above water with clear open sky above it, and perform a nuptial or courtship dance. Each insect has a characteristic up-and-down pattern of movement; strong wingbeats propel it upwards and forwards with the tail sloping down; when it stops moving its wings, it falls passively with the abdomen tilted upwards. Females fly into these swarms, and mating takes place in the air. A rising male clasps the thorax of a female from below using his front legs bent upwards, and inseminates her. Copulation may last just a few seconds, but occasionally a pair remains in tandem and flutters to the ground.<ref name=Spieth>{{cite journal |last=Spieth |first=Herman T. |year=1940 |title=Studies on the biology of the Ephemeroptera. II. The nuptial flight |journal=Journal of the New York Entomological Society |volume=48 |issue=4 |pages=379–390 |jstor=25004879 }}</ref> Males may spend the night in vegetation and return to their dance the following day. Although they do not feed, some briefly touch the surface to drink a little water before flying off.<ref name=Spieth/>

Females typically lay between four hundred and three thousand eggs. The eggs are often dropped onto the surface of the water; sometimes the female deposits them by dipping the tip of her abdomen into the water during flight, releasing a small batch of eggs each time, or deposits them in bulk while standing next to the water. In a few species, the female submerges and places the eggs among plants or in crevices underwater, but in general, they sink to the bottom. The incubation time is variable, depending at least in part on temperature, and may be anything from a few days to nearly a year. Eggs can go into a quiet dormant phase or [[diapause]].<ref>{{cite journal |last=Clifford |first=Hugh F. |journal=Quaestiones Entomologicae| volume=18 |pages=15–90 |year=1982 |title=Life cycles of mayflies (Ephemeroptera), with special reference to voltinism |url=http://www.ephemeroptera-galactica.com/pubs/pub_c/pubcliffordh1982p15.pdf}}</ref> The [[larva]]l growth rate is also temperature-dependent, as is the number of [[ecdysis|moults]]. At anywhere between ten and fifty, these post-embryonic moults are more numerous in mayflies than in most other insect orders. The nymphal stage of mayflies may last from several months to several years, depending on species and environmental conditions.<ref name=Dominguez/>

Around half of all mayfly species whose reproductive biology has been described are [[parthenogenetic]] (able to asexually reproduce), including both partially and exclusively parthenogenetic populations and species.<ref name=":0" />

Many species breed in moving water, where there is a tendency for the eggs and nymphs to get washed downstream. To counteract this, females may fly upriver before depositing their eggs. For example, the female [[Tisza mayfly]], the largest European species with a length of {{convert|12|cm|in|abbr=on}}, flies up to {{convert|3|km|0}} upstream before depositing eggs on the water surface. These sink to the bottom and hatch after 45 days, the nymphs [[burrow]]ing their way into the sediment where they spend two or three years before hatching into subimagos.<ref name=Robinson>{{cite book |last=Robinson |first=William H. |title=Urban Insects and Arachnids: A Handbook of Urban Entomology |url=https://books.google.com/books?id=aluUgDVYJ8wC&pg=PA192 |year=2005 |publisher=[[Cambridge University Press]] |isbn=978-1-139-44347-0 |page=192}}</ref>

When ready to emerge, several different strategies are used. In some species, the transformation of the nymph occurs underwater and the subimago swims to the surface and launches itself into the air.<ref name=McCafferty1983/> In other species, the nymph rises to the surface, bursts out of its skin, remains quiescent for a minute or two resting on the [[exuvia]]e (cast skin) and then flies upwards, and in some, the nymph climbs out of the water before transforming.<ref name=Berner>{{cite book |last1=Berner |first1=Lewis |last2=Pescador |first2=Manuel L. |title=The Mayflies of Florida |url=https://archive.org/details/mayfliesofflorid0000bern |url-access=registration |year=1988 |publisher=[[University Press of Florida]] |isbn=978-0-8130-0845-5 |page=[https://archive.org/details/mayfliesofflorid0000bern/page/108 108] }}</ref>

===Ecology===
[[File: Rainbow trout fish on water surface.jpg|thumb|[[Rainbow trout]] are among the main predators of mayflies.]]

Nymphs live primarily in streams under rocks, in decaying vegetation or in sediments. Few species live in lakes, but they are among the most prolific. For example, the emergence of one species of ''[[Hexagenia]]'' was recorded on [[Doppler weather radar]] by the shoreline of [[Lake Erie]] in 2003.<ref>{{cite web |url=http://www.pserie.psu.edu/seagrant/publications/fs/Mayfly_12-2003.pdf |title=Return of the mayfly: an indicator of an improving habitat |publisher=Pennsylvania Sea Grant |year=2003 |archive-url=https://web.archive.org/web/20070927230149/http://www.pserie.psu.edu/seagrant/publications/fs/Mayfly_12-2003.pdf |archive-date=27 September 2007 |access-date=30 May 2015 }}</ref> In the nymphs of most mayfly species, the paddle-like gills do not function as respiratory surfaces because sufficient oxygen is absorbed through the integument, instead serving to create a respiratory current. However, in low-oxygen environments such as the mud at the bottom of ponds in which ''[[Ephemera vulgata]]'' burrows, the filamentous gills act as true accessory respiratory organs and are used in gaseous exchange.<ref>{{cite journal |last=Wingfield |first=C. A. |year=1939 |title=The function of the gills of mayfly nymphs from different habitats |journal=Journal of Experimental Biology |volume=16 |issue=3 |pages=363–373 |doi=10.1242/jeb.16.3.363 |issn=1477-9145 |url=http://jeb.biologists.org/content/jexbio/16/3/363.full.pdf}}</ref>

In most species, the nymphs are [[herbivore]]s or [[detritivore]]s, feeding on [[algae]], [[diatom]]s or [[detritus]], but in a few species, they are [[predators]] of [[chironomid]] and other small insect larvae and nymphs.<ref>{{cite journal|journal=Aquatic Insects| volume=22 |year=2000| issue= 2| pages=148–159 |title= Guloptiloides: an Extraordinary New Carnivorous Genus of Baetidae (Ephemeroptera) |last1=Gattolliat |first1=Jean-Luc |last2=Sartori |first2=Michel | doi=10.1076/0165-0424(200004)22:2;1-p;ft148| s2cid=86012067 }}</ref><ref>{{cite journal|journal=Aquatic Insects| volume=8| issue=2| year=1986| title= Comparative mouthpart morphology and evolution of the carnivorous heptageniidae (Ephemeroptera) | doi=10.1080/01650428609361236 |last1=McCafferty |first1=W. P. |last2=Provonsha |first2=A. V. | pages=83–89}}</ref> Nymphs of ''[[Povilla]]'' burrow into submerged wood and can be a problem for boat owners in Asia.<ref name=thorpcovich>{{cite book|title=Thorp and Covich's Freshwater Invertebrates|edition=4th| editor=Thorp| editor2=Rogers|year=2014| publisher=[[Academic Press]] |chapter=Order Ephemeroptera| author1=Sartori, Michel| author2=Brittain, John E.|pages=873–891}}</ref> Some are able to shift from one feeding group to another as they grow, thus enabling them to utilise a variety of food resources. They process a great quantity of organic matter as nymphs and transfer a lot of phosphates and nitrates to terrestrial environments when they emerge from the water, thus helping to remove pollutants from aqueous systems.<ref name=Dominguez/> Along with [[caddisfly]] larvae and [[gastropoda|gastropod molluscs]], the grazing of mayfly nymphs has a significant impact on the [[primary producers]], the plants and algae, on the bed of streams and rivers.<ref name=Hauer>{{cite book |last1=Hauer |first1=F. Richard |last2=Lamberti |first2=Gary A.|title=Methods in Stream Ecology |url=https://books.google.com/books?id=rlclsSCF_dQC&pg=PA538 |year=2011 |publisher=[[Academic Press]] |isbn=978-0-08-054743-5 |pages=538, 561}}</ref>

The nymphs are eaten by a wide range of predators and form an important part of the aquatic [[food chain]]. Fish are among the main predators, picking nymphs off the bottom or ingesting them in the water column, and feeding on emerging nymphs and adults on the water surface. Carnivorous [[stonefly]], [[caddisfly]], [[alderfly]] and [[dragonfly]] larvae feed on bottom-dwelling mayfly nymphs, as do aquatic beetles, leeches, crayfish and [[amphibian]]s.<ref name="ThorpRogers2014">{{cite book |last1=Thorp |first1=James H. |last2=Rogers |first2=D. Christopher |title=Thorp and Covich's Freshwater Invertebrates: Ecology and General Biology |url=https://books.google.com/books?id=LB-OAwAAQBAJ&pg=PA886|date=6 September 2014 |publisher=[[Elsevier]] |isbn=978-0-12-385027-0 |page=886}}</ref> Besides the direct mortality caused by these predators, the behaviour of their potential prey is also affected, with the nymphs' growth rate being slowed by the need to hide rather than feed.<ref name=Hauer/> The nymphs are highly susceptible to [[Water pollution|pollution]] and can be useful in the [[biomonitoring]] of water bodies.<ref name=McCafferty1983/> Once they have emerged, large numbers are preyed on by birds, bats and by other insects, such as ''[[Rhamphomyia longicauda]]''.<ref name=Dominguez/>

Mayfly nymphs may serve as [[Host (biology)|hosts]] for [[parasite]]s such as [[nematode]]s and [[trematodes]]. Some of these affect the nymphs' behaviour in such a way that they become more likely to be predated.<ref>{{cite journal |last1=Vance |first1=Sarah A. |last2=Peckarsky |first2=Barbara L. |year=1997 |title=The effect of mermithid parasitism on predation of nymphal ''Baetis bicaudatus'' (Ephemeroptera) by invertebrates |journal=Oecologia |volume=110 |issue=1 |pages=147–152 |doi=10.1007/s004420050143 |pmid=28307463 |bibcode=1997Oecol.110..147V |s2cid=1164123 }}</ref><ref>{{cite journal |last1=Williams |first1=J. K. |last2=Townsend |first2=C. R. |last3=Poulin |first3=Robert |author3-link=Robert Poulin |year=2001 |title=Mermithid nematode infections and drift in the mayfly ''Deleatidium'' spp. (Ephemeroptera). |journal=Journal of Parasitology |volume=87 |issue=5 |pages=1225–1227 |doi=10.1645/0022-3395(2001)087[1225:MNIADI]2.0.CO;2 |pmid=11695410 |s2cid=24933760 }}</ref> Other nematodes turn adult male mayflies into quasi-females which haunt the edges of streams, enabling the parasites to break their way out into the aqueous environment they need to complete their life cycles.<ref name=Zimmer>{{cite book |last=Zimmer |first=Carl |title=Parasite Rex: Inside the Bizarre World of Nature's Most Dangerous Creatures |url=https://books.google.com/books?id=cHe5U83nvwcC&pg=PA84 |year=2003 |publisher=Arrow |isbn=978-0-09-945799-2 |pages=84–86}}</ref> The nymphs can also serve as [[intermediate hosts]] for the horsehair worm ''[[Paragordius varius]]'', which causes its [[definitive host]], a [[grasshopper]], to jump into water and drown.<ref>{{cite book|author1=Goater, Timothy M.|author2=Goater, Cameron P.|author3=Esch, Gerald W.|title=Parasitism: The Diversity and Ecology of Animal Parasites |url=https://books.google.com/books?id=zdtRAgAAQBAJ&pg=PA248 |year=2013 |publisher=[[Cambridge University Press]] |isbn=978-1-107-64961-3 |page=248}}</ref>

==== Effects on ecosystem functioning ====

Mayflies are involved in both [[primary production]] and [[bioturbation]]. A study in laboratory simulated streams revealed that the mayfly genus ''[[Centroptilum]]'' increased the export of [[periphyton]],<ref>{{Cite journal|title = Effects of Three Herbivores on Periphyton Communities in Laboratory Streams|journal = Journal of the North American Benthological Society|date = 1987-06-01|issn = 0887-3593|pages = 92–104|volume = 6|issue = 2|doi = 10.2307/1467219|first1 = Gary A.|last1 = Lamberti|first2 = Linda R.|last2 = Ashkenas|first3 = Stan V.|last3 = Gregory|first4 = Alan D.|last4 = Steinman|jstor = 1467219|s2cid = 54578281}}</ref> thus indirectly affecting primary production positively, which is an essential process for ecosystems. The mayfly can also reallocate and alter the nutrient availability in aquatic habitats through the process of bioturbation. By burrowing in the bottom of lakes and redistributing nutrients, mayflies indirectly regulate phytoplankton and epibenthic primary production.<ref>{{Cite journal |last1 = Bachteram |first1 = André M. |last2 = Mazurek |first2 = Kerry A. |last3 = Ciborowsk |first3 = Jan J. H. |title = Sediment Suspension by Burrowing Mayflies (Hexagenia spp., Ephemeroptera: Ephemeridae)|journal = Journal of Great Lakes Research|date = 2005-01-01|pages = 208–222|volume = 31 |issue=Supplement 2|series = Lake Erie Trophic Status Collaborative Study |doi = 10.1016/S0380-1330(05)70315-4}}</ref> Once burrowing to the bottom of the lake, mayfly nymphs begin to billow their respiratory gills. This motion creates current that carries food particles through the burrow and allows the nymph to filter feed. Other mayfly nymphs possess elaborate filter feeding mechanisms like that of the genus ''[[Isonychia]]''. The nymph have forelegs that contain long bristle-like structures that have two rows of hairs. Interlocking hairs form the filter by which the insect traps food particles. The action of filter feeding has a small impact on water purification but an even larger impact on the convergence of small particulate matter into matter of a more complex form that goes on to benefit consumers later in the food chain.<ref>{{Cite journal |last1=Merritt |first1=Richard W. |last2=Wallace |first2=J. Bruce |date=April 1981 |title=Filter-feeding Insects |journal=Scientific American |volume=244 |issue=4 |pages=132–136, 141–142, 144 |url=http://coweeta.uga.edu/publications/671.pdf |doi=10.1038/scientificamerican0481-132 |bibcode=1981SciAm.244d.132M |access-date=2017-01-08|archive-date=2010-06-12 |archive-url=https://web.archive.org/web/20100612033203/http://coweeta.uga.edu/publications/671.pdf}}</ref>

=== Distribution ===

Mayflies are distributed all over the world in clean freshwater habitats,<ref name=NC/> though absent from Antarctica.<ref name="Riffenburgh2007">{{cite book |last=Riffenburgh |first=Beau |title=Encyclopedia of the Antarctic |url=https://books.google.com/books?id=fRJtB2MNdJMC&pg=PA531 |year=2007 |publisher=[[Taylor & Francis]] |isbn=978-0-415-97024-2 |page=531}}</ref> They tend to be absent from oceanic islands or represented by one or two species that have dispersed from nearby mainland. Female mayflies may be dispersed by wind, and eggs may be transferred by adhesion to the legs of waterbirds.<ref>{{cite journal |last=Edmunds Jr. |first=George F. |title= Biogeography and Evolution of Ephemeroptera | journal= Annual Review of Entomology | volume=17 | pages= 21–42 |year=1972| doi=10.1146/annurev.en.17.010172.000321 }}</ref> The greatest generic diversity is found in the [[Neotropical realm]], while the [[Holarctic]] has a smaller number of genera but a high degree of speciation. Some thirteen families are restricted to a single [[bioregion]].<ref>{{cite book |last1=Barber-James |first1=Helen M. |last2=Gattolliat |first2=Jean-Luc |last3=Sartori |first3=Michel |last4=Hubbard |first4=Michael D. |title=Freshwater Animal Diversity Assessment |chapter=Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater |series=Developments in Hydrobiology |year=2008 |volume=198 |pages=339–350 |doi=10.1007/978-1-4020-8259-7_37 |isbn=978-1-4020-8258-0 }}</ref> The main families have some general habitat preferences: the [[Baetidae]] favour warm water; the [[Heptageniidae]] live under stones and prefer fast-flowing water; and the relatively large [[Ephemeridae]] make burrows in sandy lake or river beds.<ref name=NC>{{cite web |title=Ephemeroptera |url=https://projects.ncsu.edu/cals/course/ent425/library/compendium/ephemeroptera.html |website=General Entomology |publisher=[[University of North Carolina]] |access-date=10 July 2015 |archive-date=9 January 2017 |archive-url=https://web.archive.org/web/20170109022807/https://projects.ncsu.edu/cals/course/ent425/library/compendium/ephemeroptera.html  }}</ref>

== Conservation ==

The nymph is the dominant life history stage of the mayfly. Different insect species vary in their tolerance to water pollution, but in general, the larval stages of mayflies, stoneflies (Plecoptera) and caddis flies (Trichoptera) are susceptible to a number of pollutants including [[sewage]], [[pesticide]]s and [[industrial effluent]]. In general, mayflies are particularly sensitive to [[Freshwater acidification|acidification]], but tolerances vary, and certain species are exceptionally tolerant to [[Toxic heavy metal|heavy metal]] contamination and to low [[pH]] levels. [[Ephemerellidae]] are among the most tolerant groups and [[Siphlonuridae]] and [[Caenidae]] the least. The adverse effects on the insects of pollution may be either lethal or sub-lethal, in the latter case resulting in altered enzyme function, poor growth, changed behaviour or lack of reproductive success. As important parts of the food chain, pollution can cause knock-on effects to other organisms; a dearth of herbivorous nymphs can cause overgrowth of algae, and a scarcity of predacious nymphs can result in an over-abundance of their prey species.<ref name=Capinera>{{cite book |last=Capinera |first=John L. |title=Encyclopedia of Entomology |url=https://books.google.com/books?id=i9ITMiiohVQC&pg=PA4158 |year=2008 |publisher=[[Springer Science+Business Media]] |isbn=978-1-4020-6242-1 |pages=4158–4165 }}</ref> Fish that feed on mayfly nymphs that have [[Bioaccumulation|bioaccumulated]] heavy metals are themselves at risk.<ref>{{cite book |last1=Di Giulio |first1=Richard T. |last2=Hinton |first2=David E. |title=The Toxicology of Fishes |url=https://books.google.com/books?id=aOfEXLNMLugC&pg=PA794 |year=2008 |publisher=[[CRC Press]] |isbn=978-0-203-64729-5 |page=794}}</ref> Adult female mayflies find water by detecting the [[polarization (waves)|polarization]] of reflected light. They are easily fooled by other polished surfaces which can act as traps for swarming mayflies.<ref name=polarized />

The threat to mayflies applies also to their eggs. "Modest levels" of pollution in rivers in England are sufficient to kill 80% of mayfly eggs, which are as vulnerable to pollutants as other life-cycle stages; numbers of the [[blue-winged olive mayfly]] (''Baetis'') have fallen dramatically, almost to none in some rivers. The major pollutants thought to be responsible are fine sediment and phosphate from agriculture and sewage.<ref>{{cite news |last=Carrington |first=Damian |title=Insect declines: new alarm over mayfly is 'tip of iceberg', warn experts |url=https://www.theguardian.com/environment/2018/jan/11/insect-declines-new-alarm-over-mayfly-is-tip-of-iceberg-warn-experts |access-date=11 January 2018 |work=The Guardian |date=11 January 2018}}</ref>

The status of many species of mayflies is unknown because they are known from only the original collection data. Four North American species are believed to be extinct. Among these, ''[[Pentagenia robusta]]'' was originally collected from the [[Ohio River]] near [[Cincinnati]], but this species has not been seen since its original collection in the 1800s. ''[[Ephemera compar]]'' is known from a single specimen, collected from the "foothills of Colorado" in 1873, but despite intensive surveys of the Colorado mayflies reported in 1984, it has not been rediscovered.<ref>{{cite journal |last1=Edmunds |first1=G. F. Jr. |last2=McCafferty |first2=W. P. |year=1984 |title=''Ephemera compar'': an obscure Colorado burrowing mayfly (Ephemeroptera: Ephemeridae) |journal=Entomological News |volume=95 |pages=186–188 |url=http://www.ephemeroptera-galactica.com/pubs/pub_e/pubedmundsg1984p186.pdf }}</ref>

The [[International Union for Conservation of Nature]] (IUCN) [[red list]] of threatened species includes one mayfly: ''[[Tasmanophlebia lacuscoerulei]]'', the large blue lake mayfly, which is a native of Australia and is listed as [[endangered]] because its alpine habitat is [[vulnerable to climate change]].<ref>{{Cite iucn |last=Suter |first=P. |title=''Tasmanophlebi lacuscoerulei'' |volume=2014 |page=e.T40728A21425993 |date=2014 |doi=10.2305/IUCN.UK.2014-1.RLTS.T40728A21425993.en }}</ref>

==Taxonomy and phylogeny==

[[File:Mickoleitia longimanus.jpg|thumb|Fossil adult ''Mickoleitia longimanus'' ([[Coxoplectoptera]]: [[Mickoleitiidae]]) from the [[Lower Cretaceous]] [[Crato Formation]] of [[Brazil]], c. 108 [[mya (unit)|mya]]]]

Ephemeroptera was defined by [[Alpheus Hyatt]] and [[Jennie Maria Arms Sheldon]] in 1890–1.<ref>{{cite book |last1=Hyatt |first1=Alpheus |author1-link=Alpheus Hyatt |last2=Arms |first2=Jennie Maria |author2-link=Jennie Maria Arms Sheldon |title=Guides for Science-Teaching, No. VIII. Insecta |place=Boston|publisher=D. C. Heath & Co. Publishers|year=1890|url=https://www.biodiversitylibrary.org/page/14554998}}</ref><ref>{{cite journal |last1=Hyatt |first1=Alpheus |author1-link=Alpheus Hyatt |last2=Arms |first2=Jennie Maria |author2-link=Jennie Maria Arms Sheldon |title=A novel diagrammatic representation of the orders of insects |journal=Psyche: A Journal of Entomology |year=1891 |volume=6 |issue=177 |pages=11–13 |url=https://www.biodiversitylibrary.org/page/13265146#page/27/mode/1up}}</ref> The taxonomy of the Ephemeroptera was reworked by [[George F. Edmunds (entomologist)|George F. Edmunds]] and [[Jay Traver|Jay R Traver]], starting in 1954.<ref>{{cite journal |last1=Edmunds |first1=G. F. Jr. |last2=Traver |first2=J. R |author2-link=Jay Traver |year=1954 |title=An outline of a reclassification of the Ephemeroptera |journal=Proceedings of the Entomological Society of Washington |issue=56 |pages=236–240}}</ref><ref>{{cite journal |last1=Edmunds |first1=G. F. Jr. |last2=Traver |first2=J. R |author2-link=Jay Traver |year=1954 |title=The classification of the Ephemeroptera. I. Ephemeroidea: Behningiidae |journal=Annual Review of the Entomological Sociwety of America |issue=52 |pages=43–51}}</ref> Traver contributed to the 1935 work ''The Biology of Mayflies'',<ref>{{cite book |last1=Needham |first1=James G. |last2=Traver |first2=Jay R |last3=Hsu |first3=Yin-chi |title=The Biology of Mayflies with a Systematic Account of North American Species |date=1935 |publisher=Comstock |location=Ithaca, New York |oclc=814047 |pages=759, color frontispiece, monochrome illustrations, diagrams |url=https://babel.hathitrust.org/cgi/pt?id=mdp.39015004576099&view=1up&seq=9}}</ref> and has been called "the first Ephemeroptera specialist in North America".<ref name="Peters Peters 1975">{{cite journal |last1=Peters |first1=William L. |author1-link=William L. Peters |last2=Peters |first2=Janice |title=Eatonia [Jay R Traver Obituary Issue] |date=May 5, 1975 |journal=Eatonia |issue=20 |page=1 |url=https://dc.swosu.edu/eatonia/20}}</ref>

As of 2012, over 3,000 species of mayfly in 42 families and over 400 genera are known worldwide,<ref>{{cite book |last1=Bauernfeind |first1=Ernst |last2=Soldan |first2=Tomas |title=The Mayflies of Europe (Ephemeroptera)|url=https://books.google.com/books?id=CZyXCgAAQBAJ&pg=PA35 |year=2012 |publisher=[[Brill Publishers]] |isbn=978-90-04-26088-7 |page=35}}</ref><ref>{{cite journal |last1=Barber-James |first1=Helen M. |last2=Gattolliat |first2=Jean-Luc |last3=Sartori |first3=Michel |last4=Hubbard |first4=Michael D. |title=Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater |journal=Hydrobiologia |date=2008 |volume=595 |pages=339–350 |doi=10.1007/s10750-007-9028-y |s2cid=29423209 |url=https://link.springer.com/chapter/10.1007%2F978-1-4020-8259-7_37#page-2|url-access=subscription }}</ref> including about 630 species in [[North America]].<ref>{{cite web |url=http://www.ento.csiro.au/education/insects/ephemeroptera.html |title=CSIRO page for Ephemeroptera |access-date=2 August 2015}}</ref> Mayflies are an ancient group of winged (pterygote) insects. Putative fossil [[stem group]] representatives (e.g. Syntonopteroidea-like ''Lithoneura lameerrei'') are already known from the late [[Carboniferous]].<ref name="GrimaldiEngel2005"/> The name Ephemeroptera is from the [[Ancient Greek|Greek]] ἐφήμερος, ''{{lang|el|ephemeros}}'' "short-lived" (literally "lasting a day", cf. English "[[ephemeral]]"), and πτερόν, ''{{lang|el|pteron}}'', "[[insect wing|wing]]", referring to the brief lifespan of adults. The English common name is for the insect's emergence in or around the month of May in the UK.<ref>{{cite web |title=Mayfly| url=http://www.finedictionary.com/mayfly.html |publisher=Cited to Chambers's Twentieth Century Dictionary |access-date=10 July 2015}}</ref> The name shadfly is from the Atlantic fish the [[shad]], which runs up American East Coast rivers at the same time as many mayflies emerge.<ref>{{cite web |title=Shad (n.) |url=http://www.etymonline.com/index.php?term=shad |publisher=[[Online Etymology Dictionary]] |access-date=10 July 2015}}</ref><ref>{{cite web |last1=Mertz |first1=Leslie |title=How to Survive a Massive Mayfly Swarm |url=https://entomologytoday.org/2015/06/01/how-to-survive-a-massive-mayfly-swarm/ |publisher=[[Entomology Today]] |access-date=7 March 2018 |date=1 June 2015 |quote=Regional colloquialisms include fishflies, shadflies, and a slew of other names that aren't fit to print.}}</ref>

From the [[Permian]], numerous stem group representatives of mayflies are known, which are often lumped into a separate taxon [[Permoplectoptera]] (e.g. including ''Protereisma permianum'' in the [[Protereismatidae]],<ref name="GrimaldiEngel2005"/> and [[Misthodotidae]]). The larvae of Permoplectoptera still had 9 pairs of abdominal gills, and the adults still had long hindwings. Maybe the fossil family [[Cretereismatidae]] from the [[Lower Cretaceous]] [[Crato Formation]] of Brazil also belongs as the last offshoot to Permoplectoptera. The Crato outcrops otherwise yielded fossil specimens of modern mayfly families or the extinct (but modern) family Hexagenitidae. However, from the same locality the strange larvae and adults of the extinct family [[Mickoleitiidae]] (order [[Coxoplectoptera]]) have been described,<ref>{{cite journal|last1=Staniczek |first1=A. H. |last2=Bechly |first2=G. |last3=Godunko |first3=R.J. |year=2011 |title=Coxoplectoptera, a new fossil order of Palaeoptera (Arthropoda: Insecta), with comments on the phylogeny of the stem group of mayflies (Ephemeroptera) |journal=Insect Systematics & Evolution |volume=42 |issue=2 |pages=101–138 |doi=10.1163/187631211X578406}}</ref> which represents the fossil sister group of modern mayflies, even though they had very peculiar adaptations such as [[Raptor (bird)|raptorial]] forelegs.

The oldest mayfly inclusion in [[amber]] is ''Cretoneta zherichini'' (Leptophlebiidae) from the Lower Cretaceous of [[Siberia]]. In the much younger [[Baltic amber]] numerous inclusions of several modern families of mayflies have been found (Ephemeridae, Potamanthidae, Leptophlebiidae, Ametropodidae, Siphlonuridae, Isonychiidae, Heptageniidae, and Ephemerellidae).<ref>{{cite book |last=Poinar |first=G. O. Jr. |year=1992 |title=Life in Amber |publisher=[[Stanford University Press]] |url=https://books.google.com/books?id=J72FOr6AZOEC&pg=PA97 |page=97 |isbn=978-0-8047-2001-4}}</ref> The modern genus ''[[Neoephemera]]'' is represented in the fossil record by the [[Ypresian]]<ref name="M&A2009">{{cite journal |last1=Makarkin |first1=V. N. |last2=Archibald |first2=S. B. |year=2009 |title=A new genus and first Cenozoic fossil record of moth lacewings (Neuroptera: Ithonidae) from the Early Eocene of North America |journal=[[Zootaxa]] |volume=2063 |pages=55–63 |url= http://www.mapress.com/zootaxa/2009/f/zt02063p063.pdf|doi=10.11646/zootaxa.2063.1.3 |s2cid=13922025 }}</ref> species ''[[Neoephemera antiqua|N.&nbsp;antiqua]]'' from [[Washington state]].<ref name="Sinitchenkova1999">{{Cite journal |last1=Sinitshenkova |first1=N. D. |title=A new mayfly species of the extant genus ''Neoephemera'' from the Eocene of North America (Insecta: Ephemerida = Ephemeroptera: Neoephemeridae) |journal=[[Paleontological Journal]] |year=1999 |volume=33 |issue=4 |pages=403–405|url=http://www.ephemeroptera-galactica.com/pubs/pub_s/pubsinitshenkovan1999p403.pdf}}</ref>

Grimaldi and Engel, reviewing the [[Evolution of insects|phylogeny]] in 2005, commented that many [[cladistic]] studies had been made with no stability in Ephemeroptera suborders and infraorders; the traditional division into Schistonota and Pannota was wrong because Pannota is derived from the Schistonota.<ref name="GrimaldiEngel2005">{{cite book |last1=Grimaldi |first1=David |last2=Engel |first2=Michael S.|title=Evolution of the Insects |url=https://books.google.com/books?id=Ql6Jl6wKb88C&pg=PA163 |date= 2005 |publisher=[[Cambridge University Press]] |isbn=978-0-521-82149-0 |pages=162–165}}</ref>
The phylogeny of the Ephemeroptera was first studied using molecular analysis by Ogden and Whiting in 2005. They recovered the [[Baetidae]] as sister to the other clades.<ref>{{cite journal |last1=Ogden |first1=T. H. |last2=Whiting|first2=M. F. |title=Phylogeny of Ephemeroptera (mayflies) based on molecular evidence. |journal=Molecular Phylogenetics and Evolution |date=2005 |volume=37 |issue=3 |pages=625–643 |doi=10.1016/j.ympev.2005.08.008 |pmid=16214375}}</ref>
Mayfly phylogeny was further studied using morphological and molecular analyses by Ogden and others in 2009. They found that the Asian genus ''Siphluriscus'' was sister to all other mayflies. Some existing lineages such as [[Ephemeroidea]], and families such as Ameletopsidae, were found not to be [[monophyletic]], through convergence among nymphal features.<ref>{{cite journal |last1=Ogden |first1=T. H. |author2=Gattolliat, J. L. |author3=Sartori, M. |author4=Staniczek, A. H. |author5=Soldán, T. |author6=Whiting, M. F. |date=2009 |title=Towards a new paradigm in mayfly phylogeny (Ephemeroptera): combined analysis of morphological and molecular data | journal=Systematic Entomology |volume=34 |issue=4 |pages=616–634 |doi= 10.1111/j.1365-3113.2009.00488.x|s2cid=40414249 }}</ref>

The following traditional classification, with two suborders [[Pannota]] and [[Schistonota]], was introduced in 1979 by W. P. McCafferty and George F. Edmunds.<ref>{{cite journal |last1=McCafferty |first1=W. P. |last2=Edmunds |first2=George F. |title=The Higher Classification of the Ephemeroptera and Its Evolutionary Basis |journal=Annals of the Entomological Society of America |date=1979 |issue=72 |pages=5–12 |url=http://insecta.bio.spbu.ru/z/pdf/McCaffertyEdmunds1979p5.pdf}}</ref> The list is based on Peters and Campbell (1991), in ''Insects of Australia''.<ref>{{cite web |url=http://tolweb.org/tree?group=Ephemeroptera&contgroup=Pterygota |title=Ephemoptera: Mayflies |year=2002 |work=The Tree of Life Web Project |access-date=1 June 2015 |archive-date=29 June 2009 |archive-url=https://web.archive.org/web/20090629195522/http://tolweb.org/tree?group=Ephemeroptera&contgroup=Pterygota  }}</ref>

{{col-begin|width=100%}}
{{col-1-of-3}}
Suborder [[Pannota]]
*Superfamily [[Ephemerelloidea]]
**[[Ephemerellidae]]
**[[Leptohyphidae]]
**[[Tricorythidae]]
*Superfamily [[Caenoidea]]
**[[Neoephemeridae]]
**[[Baetiscidae]]
**[[Caenidae]]
**[[Prosopistomatidae]]
{{col-2-of-3}}
Suborder [[Schistonota]]
*Superfamily [[Baetoidea]]
**[[Siphlonuridae]]
**[[Baetidae]]
**[[Oniscigastridae]]
**[[Ameletopsidae]]
**[[Ametropodidae]]
*Superfamily [[Heptagenioidea]]
**[[Coloburiscidae]]
**[[Oligoneuriidae]]
**[[Isonychiidae]]
**[[Heptageniidae]]
{{col-3-of-3}}

*Superfamily [[Leptophlebioidea]]
**[[Leptophlebiidae]]
*Superfamily [[Ephemeroidea]]
**[[Behningiidae]]
**[[Potamanthidae]]
**[[Euthyplociidae]]
**[[Polymitarcyidae]]
**[[Ephemeridae]]
**[[Palingeniidae]]
{{col-end}}

=== Phylogeny ===

After<ref name=":0">{{Cite journal |last1=Liegeois |first1=Maud |last2=Sartori |first2=Michel |last3=Schwander |first3=Tanja |date=2021-03-12 |editor-last=Orive |editor-first=Maria |title=Extremely Widespread Parthenogenesis and a Trade-Off Between Alternative Forms of Reproduction in Mayflies (Ephemeroptera) |url=https://academic.oup.com/jhered/article/112/1/45/5904753 |journal=Journal of Heredity |language=en |volume=112 |issue=1 |pages=45–57 |doi=10.1093/jhered/esaa027 |issn=0022-1503 |pmc=7953839 |pmid=32918457}}</ref>
{{Clade|{{Clade
   |1=[[Siphluriscidae]]
   |2={{Clade
      |1=[[Baetidae]]
      |2={{Clade
         |label1=Carapacea
         |1={{Clade
            |1=[[Baetiscidae]]
            |2=[[Prosopistomatidae]]
            }}
         |2={{Clade
            |1={{Clade
               |1=[[Coloburiscidae]]
               |2={{Clade
                  |1=[[Leptophlebiidae]]
                  |2={{Clade
                     |1={{Clade
                        |1=[[Chromarcyidae]]
                        |2=[[Oligoneuriidae]]
                        }}
                     |2={{Clade
                        |1={{Clade
                           |1=[[Vietnamellidae]]
                           |2={{Clade
                              |1=[[Austremerellidae]]
                              |2={{Clade
                                 |1={{Clade
                                    |1=[[Teloganodidae]]
                                    |2={{Clade
                                       |1={{Clade
                                          |1=[[Teloganellidae]]
                                          |2=[[Melanemerellidae]]
                                          }}
                                       |2={{Clade
                                          |1=[[Ephemerythidae]]
                                          |2={{Clade
                                             |1=[[Machadorythidae]]
                                             |2={{Clade
                                                |1={{Clade
                                                   |1=[[Tricorythidae]]
                                                   |2=[[Dicercomyzidae]]
                                                   }}
                                                |2={{Clade
                                                   |1=[[Coryphoridae]]
                                                   |2=[[Leptohyphidae]]
                                    }} }} }} }} }} }}
                                 |2=[[Ephemerellidae]]
                           }} }} }}
                        |label1=Ephemerelloidea
                        |label2=Caenoidea
                        |2={{Clade
                           |1=[[Neoephemeridae]]
                           |2=[[Caenidae]]
                           }}
                        |3={{Clade
                           |1=[[Potamanthidae]]
                           |2={{Clade
                              |1=[[Polymitarcyidae]]
                              |2={{Clade
                                 |1={{Clade
                                    |1=[[Behningiidae]]
                                    |2=[[Euthyplociidae]]
                                    }}
                                 |2={{Clade
                                    |1=[[Ichthybotidae]]
                                    |2={{Clade
                                       |1=[[Palingeniidae]]
                                       |2=[[Ephemeridae]]
               }} }} }} }} }} }} }} }} }}
            |2={{Clade
               |1={{Clade
                  |1=[[Acanthametropodidae]]
                  |2=[[Ametropodidae]]
                  }}
               |2=[[Metropodidae]]
               |3={{Clade
                  |1=[[Isonychiidae]]
                  |2=[[Heptageniidae]]
                  }}
               |4={{Clade
                  |1={{Clade
                     |1={{Clade
                        |1=[[Rallidentidae]]
                        |2=[[Siphlaenigmatidae]]
                        |3=[[Dipteromimidae]]
                        |4=[[Oniscigastridae]]
                        }}
                     |2=[[Ameletopsidae]]
                     }}
                  |2={{Clade
                     |1=[[Nesameletidae]]
                     |2={{Clade
                        |1=[[Ameletidae]]
                        |2=[[Siphlonuridae]]
}} }} }} }} }} }} }} }}|style=font-size:85%; line-height:85%}}

==In human culture==

===In art===

The [[Dutch Golden Age]] author Augerius Clutius ([[:de:Outgert Cluyt|Outgert Cluyt]]) illustrated some mayflies in his 1634 ''De Hemerobio'' ("On the Mayfly"), the earliest book written on the group. [[Maerten de Vos]] similarly illustrated a mayfly in his 1587 depiction of the fifth day of creation, amongst an assortment of fish and water birds.<ref>{{cite book |author=Jorink, Eric |title=Reading the Book of Nature in the Dutch Golden Age, 1575–1715 |url=https://books.google.com/books?id=XAiEMHlll9QC&pg=PA200 |year=2010 |publisher=[[Brill Publishers|Brill]] |isbn=978-90-04-18671-2 |page=200}}</ref><ref name="Enenkel2014">{{cite book |last=Enenkel |first=K.A.E. |title=Zoology in Early Modern Culture: Intersections of Science, Theology, Philology, and Political and Religious Education |url=https://books.google.com/books?id=KQoSBQAAQBAJ&pg=PA366 |date=2014 |publisher=[[Brill Publishers|Brill]] |isbn=978-90-04-27917-9 |page=366}}</ref>

In 1495 [[Albrecht Dürer]] included a mayfly in his engraving ''[[The Holy Family with the Mayfly]]''.<ref name=NGA>{{cite web |title=The Holy Family with the Mayfly 1495/1496 |url=http://www.nga.gov/content/ngaweb/Collection/art-object-page.6571.html |publisher=[[National Gallery of Art]] |access-date=14 March 2015}}</ref> The critics [[Larry Silver]] and [[Pamela H. Smith]] argue that the image provides "an explicit link between heaven and earth ... to suggest a cosmic resonance between sacred and profane, celestial and terrestrial, macrocosm and microcosm."<ref name="SmithFindlen2013">{{cite book |last1=Smith |first1=Pamela |last2=Findlen |first2=Paula |title=Merchants and Marvels: Commerce, Science, and Art in Early Modern Europe |url=https://books.google.com/books?id=LUuMAQAAQBAJ&pg=PA31 |year=2013 |publisher=[[Taylor & Francis]] |isbn=978-1-135-30035-7 |page=31}}</ref>

{| class="center toccolours"
|+ '''Mayfly in art'''
|<gallery mode="packed" heights="140" style="line-height:130%">
File:Clutius 1634 De Hemerobio mayflies.jpg|Mayflies drawn by Augerius Clutius{{efn|Clutius is the latinised form of [[:de:Outgert Cluyt|Outgert Cluyt]] (1578–1636).}} in ''De Hemerobio'', 1634
File:Jan Sadeler after Maarten de Vos Heron Mayfly Flying Fish 1587.jpg|Mayfly by [[Jan Sadeler]] after [[Maerten de Vos]], detail from ''The Fifth Day: The Creation of the Birds and Fishes'', c. 1587
File:Albrecht Dürer - The Holy Family with the Mayfly (NGA 1943.3.3453).jpg|[[Albrecht Dürer]]'s engraving ''[[The Holy Family with the Mayfly]]'', 1495
File:Insect in Dürer's Holy Family with the Mayfly detail.jpg|Detail of "mayfly" in lower right corner of [[Albrecht Dürer]]'s engraving ''[[The Holy Family with the Mayfly]]'', 1495
File:Mayflies in Sunset Dance Gilbert White Natural History of Selborne.jpg|"May-Flies in Sunset Dance" by [[Philip Henry Gosse]] in a Victorian edition of [[Gilbert White]]'s ''[[Natural History of Selborne]]''
</gallery>
|-
| style="text-align:left" | 
|}

=== In literature ===

The [[Ancient Greek philosophy|Ancient Greek]] [[Aristotle's biology|biologist]] and philosopher [[Aristotle]] wrote in his ''[[History of Animals]]'' that

{{Blockquote|Bloodless and many footed animals, whether furnished with wings or feet, move with more than four points of motion; as, for instance, the dayfly (ephemeron) moves with four feet and four wings: and, I may observe in passing, this creature is exceptional not only in regard to the duration of its existence, whence it receives its name, but also because though a quadruped it has wings also.<ref>{{cite book |last1=Aristotle |title=History of Animals |page=490 a–b}}</ref>{{efn|Mayflies such as ''Hexagenia'' use 4 legs for walking; the male's front pair are specialised as claspers to hold the female during the mating flight. Aristotle also describes the mayfly in ''[[History of Animals]]'', 552b.<ref name="Scarborough1992">{{cite book |last=Scarborough |first=John |title=Medical and Biological Terminologies: Classical Origins |url=https://books.google.com/books?id=hjwN65nZBE0C&pg=PA91 |year=1992 |publisher=[[University of Oklahoma Press]] |isbn=978-0-8061-3029-3 |page=91}}</ref>}}}}

The [[Ancient Roman]] encyclopaedist [[Pliny the Elder]] described the mayfly as the "hemerobius" in his ''[[Natural History (Pliny)|Natural History]]'':

{{Blockquote|The [[River Bug]] on the [[Black Sea]] at midsummer brings down some thin membranes that look like berries out of which burst a four-legged caterpillar in the manner of the creature mentioned above, but it does not live beyond one day, owing to which it is called the hemerobius.<ref>{{cite book |author=Pliny the Elder |translator=Rackham, H. |title=Natural History |url=https://archive.org/stream/plinynaturalhist005560mbp#page/n521/mode/2up/search/hemerobius |date=1947 |orig-date=79 |publisher=William Heinemann |volume=III |page=507}} (NH Book XI. XLIII)</ref>}}

The Roman lawyer [[Cicero, Marcus Tullius|Cicero]] wrote philosophically of them in his [[Tusculan Disputations]]: 

{{blockquote|Artistotle saith there is a kind of insect near the river Hypanis, which runs from a certain part of Europe into the Pontus, whose life consists but of one day; those that die at the eighth hour die in full age; those who die when the sun sets are very old, especially when the days are at the longest. Compare our longest life with eternity, and we shall be found almost as short-lived as those little animals.<ref>{{cite book |author=[[Cicero|Marcus Tullius Cicero]] |translator=Andrew Preston Peabody |year=1886 |title=Tusculan Disputations |publisher=Little, Brown and Company |url=https://archive.org/details/cicerostusculand00ciceiala/page/69/mode/1up?q=hypanis}}</ref>}}

In his 1789 book ''[[The Natural History and Antiquities of Selborne]]'', [[Gilbert White]] described in the entry for "June 10th, 1771" how

{{Blockquote|Myriads of May-flies appear for the first time on the [[New Alresford|Alresford]] stream. The air was crowded with them, and the surface of the water covered. Large trouts sucked them in as they lay struggling on the surface of the stream, unable to rise till their wings were dried ... Their motions are very peculiar, up and down for so many yards almost in a perpendicular line.<ref name="White1837">{{cite book |last=White |first=Gilbert |title=The Natural History and Antiquities of Selborne |url=https://archive.org/details/nathistantiqselb00whitrich |year=1837 |publisher=Printed for J. and A. Arch |page=[https://archive.org/details/nathistantiqselb00whitrich/page/469 469]}}</ref>}}

The mayfly has come to symbolise the transitoriness and brevity of life.<ref>{{cite web |last=Kreiger |first=Georgia |title=Mayfly |publisher=Hippocampus Magazine |date=2 August 2012 |url=http://www.hippocampusmagazine.com/2012/08/mayfly-by-georgia-kreiger/ |access-date=14 March 2015}}</ref> The English poet [[George Crabbe]], known to have been interested in insects,<ref name="Pollard2003">{{cite book |last=Pollard |first=Arthur |title=George Crabbe: The Critical Heritage |url=https://books.google.com/books?id=XYOGAgAAQBAJ&pg=PA410 |year=2003 |publisher=[[Routledge]] |isbn=978-1-134-78243-7 |pages=409–410}}</ref> compared the brief life of a [[newspaper]] with that of mayflies, both being known as "Ephemera",<ref>{{cite web |title=Ephemera |url=http://www.thefreedictionary.com/ephemera | publisher=The Free Dictionary |access-date=14 March 2015}}</ref> things that live for a day:<ref>{{cite book |last=Crabbe |first=George |author-link=George Crabbe |title=The Village and the Newspaper by George Crabbe |url=http://www.gutenberg.org/ebooks/5203 |publisher=Gutenberg.org |access-date=14 March 2015 |date=March 2004}}</ref>

{{Blockquote|<poem>In shoals the hours their constant numbers bring
Like insects waking to th' advancing spring;
Which take their rise from grubs obscene that lie
In shallow pools, or thence ascend the sky:
Such are these base ephemeras, so born
To die before the next revolving morn.</poem>|George Crabbe, "The Newspaper", 1785}}

The theme of brief life is echoed in the artist Douglas Florian's 1998 poem, "The Mayfly".<ref>{{cite web |last=Florian |first=Douglas |title=The Mayfly |url=http://www.poetryfoundation.org/poem/176365 |publisher=The Poetry Foundation |access-date=2 June 2015}}</ref> The [[Poet Laureate Consultant in Poetry to the Library of Congress|American Poet Laureate]] [[Richard Wilbur]]'s 2005 poem "Mayflies" includes the lines "I saw from unseen pools a mist of flies, In their quadrillions rise, And animate a ragged patch of glow, With sudden glittering".<ref>{{cite web |last=Wilbur |first=Richard |author-link=Richard Wilbur |title=Mayflies |url=http://www.poetryarchive.org/poem/mayflies |publisher=Poetry Archive |access-date=2 June 2015}}</ref>

Another literary reference to mayflies is seen in ''[[The Epic of Gilgamesh]]'', one of the earliest surviving great works of literature. The briefness of Gilgamesh's life is compared to that of the adult mayfly.<ref name="Macadam 113–123"/> In [[Szeged]], Hungary, mayflies are celebrated in a monument near the Belvárosi bridge, the work of local sculptor Pal Farkas, depicting the courtship dance of mayflies.<ref>{{Cite journal |last1=Wennemann |first1=L. |last2=Sipos |first2=P. |last3=Wright |first3=L. C. |date=2004-04-01 |title=The Mayfly Monument and the Moth of Freedom |journal=American Entomologist |volume=50 |issue=2 |pages=87–89 |doi=10.1093/ae/50.2.87 |issn=1046-2821|doi-access=free }}</ref> The American playwright [[David Ives]] wrote a short comedic play, ''Time Flies'', in 2001, as to what two mayflies might discuss during their one day of existence.<ref>{{cite book |last1=Ives |first1=David |author-link=David Ives |title=Time Flies and Other Short Plays |publisher=[[Grove Press]] |date=2001 |url=http://www.worldcat.org/wcpa/servlet/org.oclc.lac.ui.DialABookServlet?oclcnum=44461836 <!--Excerpt: Chapter One--> |isbn=978-0-8021-3758-6}}</ref>

=== In fly fishing ===

[[File:BowlkersArtofAnglingFrontpiece Mayflies.JPG|thumb|left|upright=1.3<!--size for low image-->|[[Artificial flies|Fishing flies]] from Charles and Richard Bowlker's ''Art of Angling'' (1854) 2. "Blue Dun" mayfly. 3. "[[Rhithrogena germanica|March Brown]]" mayfly]]

Mayflies are the primary source of models for artificial flies, hooks tied with coloured materials such as threads and feathers, used in [[fly fishing]].<ref name=McCafferty1983/> These are based on different life-cycle stages of mayflies. For example, the flies known as "emergers" in North America are designed by fly fishermen to resemble subimago mayflies, and are intended to lure freshwater [[trout]].<ref>{{cite book |last=Hughes |first=Dave |title=Trout Flies – The tier's reference |publisher=[[Stackpole Books]] |year=1999 |isbn=978-0-8117-1601-7 |chapter=Mayfly Emergers |pages=170–186}}</ref> In 1983, Patrick McCafferty recorded that artificial flies had been based on 36 genera of North American mayfly, from a total of 63 western species and 103 eastern/central species. A large number of these species have common names among fly fishermen, who need to develop a substantial knowledge of mayfly "habitat, distribution, seasonality, morphology and behavior" in order to match precisely the look and movements of the insects that the local trout are expecting.<ref name=McCafferty1983/>

[[Izaak Walton]] describes the use of mayflies for catching trout in his 1653 book ''[[The Compleat Angler]]''; for example, he names the "Green-drake" for use as a natural fly, and "duns" (mayfly subimagos) as artificial flies. These include for example the "Great Dun" and the "Great Blue Dun" in February; the "Whitish Dun" in March; the "Whirling Dun" and the "Yellow Dun" in April; the "Green-drake", the "Little Yellow May-Fly" and the "Grey-Drake" in May; and the "Black-Blue Dun" in July.<ref>{{cite book |last1=Walton |first1=Izaak |title=The Complete Angler or The Contemplative Man's Recreation |date=1875 |publisher=[[Chatto & Windus]] |pages=241, 253–262 |url=https://archive.org/stream/complangler00waltrich#page/240/mode/2up}}</ref> Nymph or "wet fly" fishing was restored to popularity on the [[chalk stream]]s of England by [[G. E. M. Skues]] with his 1910 book ''[[Minor Tactics of the Chalk Stream]]''. In the book, Skues discusses the use of duns to catch trout.<ref name=Walker1-13>{{cite book |last=Walker |first=C. F. |title=The Angling Letters of G.E.M. Skues |publisher=[[A & C Black]] |year=1956}}</ref><ref>{{cite book |last=Hills |first=John Waller |title=A History of Fly Fishing for Trout |publisher=Phillip Allan & Co |year=1921 |pages=132–133 |title-link=A History of Fly Fishing for Trout}}</ref><ref>{{cite book |last=Skues |first=G. E. M. |author-link=G. E. M. Skues |title=Minor Tactics of the Chalk Stream and Kindred Studies |publisher=[[A & C Black]] |location=London |year=1914 |page=8ff |edition=2nd |url=https://archive.org/stream/minortacticsofch00skuerich#page/n7/mode/2up |quote=It has been advanced as an argument against the use of the wet fly, that duns and the other small insects which drift down upon the surface of a stream are never seen by the fish under water, and that a wet fly is therefore an unnatural object, especially if winged. "Never " is a big word, and I venture to think the case is overstated. I have watched an eddy with little swirling whirlpools in it for an hour together, and again and again I have seen little groups of flies caught in one or other of the whirls, sucked under and thrown scatterwise through the water.}}</ref> The March brown is "probably the most famous of all British mayflies", having been copied by [[angling|angler]]s to catch trout for over 500 years.<ref>{{cite web |url=https://www.buglife.org.uk/bugs-and-habitats/march-brown-mayfly |title=March brown mayfly |website=Buglife.org |access-date=4 August 2015 }}</ref><ref name=McCully>{{cite book |last=McCully |first=C.B. |year=2000 |title=The Language of Fly-Fishing |publisher=[[Taylor & Francis]] |isbn=978-1-57958-275-3 |chapter=March Brown |pages=125–126}}</ref>

Some English [[public house]]s beside trout streams such as the [[River Test]] in [[Hampshire]] are named "The Mayfly".<ref>{{cite news |last1=Miller |first1=Wendy |title=Hampshire Pub Guide: The Mayfly in Fullerton |url=https://www.telegraph.co.uk/foodanddrink/pubs/6017848/Hampshire-pub-guide-The-Mayfly-in-Fullerton.html |archive-url=https://ghostarchive.org/archive/20220112/https://www.telegraph.co.uk/foodanddrink/pubs/6017848/Hampshire-pub-guide-The-Mayfly-in-Fullerton.html |archive-date=2022-01-12 |url-access=subscription |url-status=live |newspaper=The Telegraph |access-date=30 May 2015 |date=14 August 2009}}{{cbignore}}</ref><ref>{{cite web |title=The Mayfly, Chilbolton |url=http://www.beerintheevening.com/pubs/s/15/15320/Mayfly/Chilbolton |publisher=Beer in the Evening |access-date=30 May 2015}}</ref><ref>{{cite web |title=Mayfly, Chilbolton, Wherwell, Hampshire |url=http://www.thegoodpubguide.co.uk/pub/view/Mayfly-SO20-6AX |publisher=[[The Good Pub Guide]] |access-date=30 May 2015}}</ref>

=== As a spectacle ===

The hatch of the giant mayfly ''Palingenia longicauda'' on the [[Tisza]] and [[Maros River]]s in Hungary and Serbia, known as "Tisza blooming", is a tourist attraction.<ref name=riverfly>{{cite web |url=http://www.riverfly.co.uk/interesting4.htm |title=Europe's largest mayfly |date=5 April 2011 |publisher=Teifi Rivers Invertebrate Monitors |website=Riverfly |access-date=10 January 2013 |archive-date=25 March 2016 |archive-url=https://web.archive.org/web/20160325214907/http://www.riverfly.co.uk/interesting4.htm |url-status=dead }}</ref> The 2014 hatch of the large black-brown mayfly ''[[Hexagenia bilineata]]'' on the [[Mississippi River]] in the US was imaged on weather radar; the swarm flew up to 760 m (2,500 feet) above the ground near [[La Crosse, Wisconsin]], creating a radar signature that resembled a "significant rain storm", and the mass of dead insects covering roads, cars and buildings caused a "slimy mess".<ref>{{cite web |last1=Grenoble |first1=Ryan |title=This year's mayfly hatch was so big it showed up on radar and caused a car wreck |url=http://www.huffingtonpost.com/2014/07/23/mayfly-hatch-wisconsin-photos-radar_n_5614449.html |publisher=[[HuffPost|Huffington Post]] |access-date=30 May 2015 |date=23 July 2014}}</ref>

During the weekend of 13–14 June 2015, a large swarm of mayflies caused several vehicular accidents on the [[Columbia–Wrightsville Bridge]], carrying [[Pennsylvania Route 462]] across the [[Susquehanna River]] between [[Columbia, Pennsylvania|Columbia]] and [[Wrightsville, Pennsylvania]]. The bridge had to be closed to traffic twice during that period due to impaired visibility and obstructions posed by piles of dead insects.<ref>{{cite web |url=http://abc27.com/2015/06/15/why-mayflies-swarmed-columbia-wrightsville-bridge/ |title=Why mayflies swarmed Columbia-Wrightsville bridge |date=2015-06-15}}</ref>

===As food ===

Mayflies are consumed in several cultures and are estimated to contain the most raw protein content of any edible insect by dry weight. In [[Malawi]], [[kunga cake|kungu]], a paste of mayflies (''Caenis kungu'') and mosquitoes is made into a cake for eating. Adult mayflies are collected and eaten in many parts of China and Japan. Near [[Lake Victoria]], ''Povilla'' mayflies are collected, dried and preserved for use in food preparations.<ref>{{cite book |chapter-url=http://www.ephemeroptera-galactica.com/pubs/pub_g/pubgrantp2001p107.pdf | chapter=Mayflies as food |last=Grant |first=Peter M. | title=Trends in Research in Ephemeroptera and Plecoptera |editor=Dominguez, E. | publisher=[[Wolters Kluwer|Kluwer]] | year=2001 |pages=107–124 | doi=10.1007/978-1-4615-1257-8_14| isbn=978-1-4613-5465-9 }}</ref> <!--Section is about food for HUMANS-->

=== As a name for ships and aircraft ===

[[File:1911 09 24 Vickers HMAno1 BarrowInFurness.jpg|thumb|right|[[HMA No. 1]] ''Mayfly'' emerging from her floating shed at [[Vickers]]' yard at [[Barrow-in-Furness]] on {{nowrap|24 September 1911}}]]

"Mayfly" was the crew's nickname for [[HMA No. 1|His Majesty's Airship No. 1]], an aerial scout airship built by [[Vickers]] but wrecked by strong winds in 1911 before her trial flights.<ref>{{cite journal |title=Popular Mechanics |journal=Popular Mechanics |url=https://books.google.com/books?id=-t0DAAAAMBAJ&pg=PA773 |date=December 1911 |publisher=Hearst Magazines |page=773 |issn=0032-4558}}</ref>

Two vessels of the [[Royal Navy]] were named {{HMS|Mayfly}}: a torpedo boat launched in January 1907,<ref>{{cite book |last=Randall |first=Ian |title=Conway's All the World's Fighting Ships 1906–1921 | publisher=Conway Maritime Press |page=72 |date=1997 | isbn=978-0-851-77245-5}}</ref> and a [[Fly-class gunboat|''Fly''-class river gunboat]] constructed in sections at Yarrow in 1915.<ref>{{Cite Colledge2006|page=106}}</ref>

The [[Seddon Mayfly]], which was constructed in 1908, was an aircraft that was unsuccessful in early flight. The first aircraft designed by a woman, [[Lilian Bland|Lillian Bland]], was titled the [[Bland Mayfly]].<ref name="Macadam 113–123"/>

===Other human uses===

In pre-1950s France, "chute de manne" was obtained by pressing mayflies into cakes and using them as [[bird food]] and fishbait.<ref name=thorpcovich/> From an economic standpoint, mayflies also provide fisheries with an excellent diet for fish.<ref name="Macadam 113–123">{{Cite journal |title=More than just fish food: ecosystem services provided by freshwater insects |journal=Ecological Entomology |date=2015 |issn=1365-2311 |pages=113–123 |volume=40 |doi=10.1111/een.12245 |first1=Craig R. |last1=Macadam |first2=Jenni A. |last2=Stockan|s2cid=84112363 |doi-access=free }}</ref> Mayflies could find uses in the biomedical, pharmaceutical, and cosmetic industries. Their exoskeleton contains [[chitin]], which has applications in these industries.<ref name="Macadam 113–123"/>

Research on genome expression in the mayfly ''[[Cloeon dipterum]],'' has provided ideas on the evolution of the insect wing and giving support to the so-called gill theory which suggests that the ancestral [[insect wing]] may have evolved from larval gills of aquatic insects like mayflies.<ref>{{cite journal |last1=Almudi |first1=Isabel |last2=Vizueta |first2=Joel |last3=Wyatt |first3=Christopher D.R. |last4=de Mendoza |first4=Alex |last5=Marlétaz |first5=Ferdinand |last6=Firbas |first6=Panos N. |last7=Feuda |first7=Roberto |last8=Masiero |first8=Giulio |last9=Medina |first9=Patricia |last10=Alcaina-Caro |first10=Ana |last11=Cruz |first11=Fernando |display-authors=6 |date=2020 |title=Genomic adaptations to aquatic and aerial life in mayflies and the origin of insect wings |journal=Nature Communications |volume=11 |issue=1 |page=2631 |doi=10.1038/s41467-020-16284-8 |issn=2041-1723 |pmc=7250882| pmid=32457347 |bibcode=2020NatCo..11.2631A }}</ref>

Mayfly larvae do not survive in polluted aquatic habitats and, thus, have been chosen as bioindicators, markers of water quality in [[ecological]] assessments.<ref>{{Cite journal |last1=Arimoro |first1=Francis Ofurum |last2=Muller |first2=Wilhelmine J. |title=Mayfly (Insecta: Ephemeroptera) community structure as an indicator of the ecological status of a stream in the Niger Delta area of Nigeria |journal=Environmental Monitoring and Assessment |date=2009 |pages=581–594 |volume=166 |issue=1–4 |doi=10.1007/s10661-009-1025-3 |pmid=19543701|s2cid=11317354 }}</ref>

In marketing, [[Nike, Inc.|Nike]] produced a line of running shoes in 2003 titled "Mayfly". The shoes were designed with a wing venation pattern like the mayfly and were also said to have a finite lifetime.<ref name="Macadam 113–123"/> The telecommunication company [[Vodafone]] featured mayflies in a 2006 branding campaign, telling consumers to "make the most of now".<ref name="Macadam 113–123"/>

== Notes ==

{{Notelist}}

== References ==

{{Reflist|28em}}

== External links ==

* {{Wikispecies-inline|Ephemeroptera}}
* {{Commons category-inline|Ephemeroptera}}
* [http://tolweb.org/tree?group=Ephemeroptera&contgroup=Pterygota Info about Ephemeroptera] {{Webarchive|url=https://web.archive.org/web/20090629195522/http://tolweb.org/tree?group=Ephemeroptera&contgroup=Pterygota |date=2009-06-29 }} on [[Tree of Life Web Project|Tree of Life]]
* [https://www.entm.purdue.edu/mayfly/ Mayfly Central] hosted by [[Purdue University]]

{{Orders of Insects}}
{{Ephemeroptera}}
{{Insects in culture}}

{{Taxonbar|from=Q174273}}
{{Authority control}}

{{DEFAULTSORT:Mayfly}}
[[Category:Mayflies| ]]
[[Category:Extant Pennsylvanian first appearances]]
[[Category:Featured articles]]
[[Category:Aquatic insects]]