Animal Diversity Web

Ge­o­graphic Range

Na­tive to North Amer­ica, Ste­nacron in­ter­punc­ta­tum is a com­mon mayfly species that is widely dis­trib­uted in the east­ern and cen­tral United States and Canada. Pop­u­la­tions occur as far west as Arkansas and Min­nesota, and hatches of S. in­ter­punc­ta­tum are not found west of Den­ver. The south­ern limit of its range ap­pears to be Florida, and the species ex­tends north to Man­i­toba. Some re­searchers sug­gest that S. in­ter­punc­ta­tum is the most com­mon species of its genus. ("Mayflies (Ephemeroptera)", 2013; Berner and Pescador, 1988; Ed­munds, et al., 1976; Kon­drati­eff, 2013a; Kon­drati­eff, 2013b; Mc­Caf­ferty and Pereira, 1984; Pescador and Ras­mussen, 1995; Schwiebert, 2007)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Ste­nacron in­ter­punc­ta­tum nymphs are aquatic, usu­ally liv­ing in streams and rivers. Stream or­gan­isms are often sen­si­tive to ther­mal con­di­tions in the water, and water tem­per­a­ture cor­re­lates with the rate of stream flow. How­ever, ac­counts vary re­gard­ing the flow rates that S. in­ter­punc­ta­tum prefers. Some stud­ies re­port that S. in­ter­punc­ta­tum nymphs pre­fer slower cur­rents, while other stud­ies claim that the nymphs occur in mod­er­ately rapid to swift rivers and streams. Ste­nacron in­ter­punc­ta­tum is a com­mon and widely dis­trib­uted species that prob­a­bly tol­er­ates a rel­a­tively broad range of en­vi­ron­men­tal con­di­tions, in­clud­ing water flow rates. This species in­hab­its wa­ters that have a pH be­tween 5.3 and 7.0.

Nymphs spend most of the day under rocks or sub­merged logs, in rock crevices, amid de­bris, and in veg­e­ta­tion. At night, nymphs may crawl to the tops of rocks. Nymphs thrive in mid-sized al­ka­line creeks. They some­times in­habit lake shores that have wave ac­tion and ob­jects to which the nymphs can cling. Since suit­able habi­tat on lake shores is rare, nymphs tend to gather at high den­si­ties in a sin­gle spot on a lake shore.

Ste­nacron in­ter­punc­ta­tum adults are ter­res­trial. Their ter­res­trial habi­tat is close to the water from which they emerged. ("Mayflies (Ephemeroptera)", 2013; Berner and Pescador, 1988; Ed­munds, et al., 1976; Flow­ers and Hilsen­hoff, 1978; Giber­son and MacKay, 1991; Lamp and Britt, 1981; Mc­Caf­ferty and Huff, 1978; Mc­Shaf­frey and Mc­Caf­ferty, 1986; Mc­Shaf­frey, 1996; Meyer, 2009; Snucins, 2003)

• Habitat Regions
• temperate
• terrestrial
• freshwater

• Terrestrial Biomes
• forest

• Aquatic Biomes
• benthic
• lakes and ponds
• rivers and streams

• Other Habitat Features
• suburban
• agricultural
• riparian

Phys­i­cal De­scrip­tion

The eggs of Ste­nacron in­ter­punc­ta­tum have polar caps, which are at­tach­ment struc­tures lo­cated at the dis­tal ends of each egg. These polar caps dis­tin­guish S. in­ter­punc­ta­tum eggs from those of re­lated mayfly species.

In gen­eral, mayfly nymphs can be dis­tin­guished from other aquatic in­sects by the wing pads on the tho­rax, three pairs of seg­mented legs, gills on the ab­domen, and three (some­times two) thin tail fil­a­ments. In S. in­ter­punc­ta­tum nymphs, the legs are striped with dis­tinct, dark bands. Early-in­star nymphs are char­ac­ter­ized by the pres­ence of gills. Ste­nacron in­ter­punc­ta­tum dif­fers from re­lated species in that its gills are pointed. Later-in­star nymphs de­velop wing pads, which con­tinue de­vel­op­ing as the in­sects molt. Dark wing pads in­di­cate that a nymph will soon emerge as a subimago (non-re­pro­duc­tive winged form). Ma­ture nymphs are 8 to 13 mm long (ex­clud­ing their tail fil­a­ments). The head and body of a ma­ture nymph are dark brown. The head is rel­a­tively large, at more than 2.5 mm wide. Like other species in the fam­ily Hep­ta­geni­idae, S. in­ter­punc­ta­tum nymphs have flat bod­ies, which al­lows them to fit into crevices and under rocks. Spines at the ends of their legs en­able the nymphs to dig into small holes and crevices. The sex of a nymph can­not be de­ter­mined until later in­star stages.

The forewings of newly hatched subima­goes are 10 to 12 mm long. Many of the veins in the wings are darkly col­ored, while some are clear. Their heads are yel­low­ish tan, and the com­pound eyes of males can be pale green.

Ste­nacron in­ter­punc­ta­tum adults have mem­bra­nous wings that can­not lay flat against their body. In­stead, the wings are held to­gether above the body when the in­sect is at rest. The forewings are larger than the hind­wings. Adult bod­ies often are yel­low­ish but can also be brown and white. The bright­ness of adult col­oration can vary with the length of time that the in­di­vid­ual de­vel­oped as a nymph. Mayflies have paired gen­i­tal open­ings.

Adult males have crys­talline forewings that are 8 to 10 mm long. Their com­pound eyes often are dull green, though the eyes can be yel­low­ish brown, with a hor­i­zon­tal stripe at the mid­dle of each eye. The eyes are large, well sep­a­rated, and ori­ented to­ward the top of the head. The length of male forelegs varies be­tween shorter to much longer than the body. Males have two penes that have a dis­tinct shape, with an un­usu­ally well-de­vel­oped clus­ter of spines on each penis.

Adult fe­males are larger than males. They have glassy forewings that are 10 to 12 mm long. Adult fe­male col­oration is sim­i­lar to that of adult males, but the col­ors are muted and less de­fined. The ova of a fe­male are pre­sent and vis­i­ble upon emer­gence, cre­at­ing the bril­liant or­ange color that can be ob­served through the translu­cent ab­domen.

Ste­nacron in­ter­punc­ta­tum pre­sents tax­o­nomic dif­fi­cul­ties, due to sub­stan­tial in­traspe­cific vari­a­tion under dif­fer­ent en­vi­ron­men­tal con­di­tions and across its ge­o­graphic range. The pat­terns of phe­no­typic vari­a­tion in the species do not fit the nor­mal sub­species con­cept. His­tor­i­cally, the species has been clas­si­fied within dif­fer­ent gen­era. Some au­thors have re­vised the genus, some have iden­ti­fied mul­ti­ple sub­species of S. in­ter­punc­ta­tum, and some have not at­tempted to sep­a­rate the sub­species. To clear up the con­fu­sion, some re­searchers showed ex­per­i­men­tally that phe­no­typic dif­fer­ences in nymphs cor­re­late with vari­a­tion in tem­per­a­ture. The re­searchers con­cluded that pre­vi­ously iden­ti­fied sub­species ac­tu­ally were all S. in­ter­punc­ta­tum. ("Mayflies (Ephemeroptera)", 2013; Berner and Pescador, 1988; Ed­munds, et al., 1976; Lewis, 1974; Mc­Caf­ferty and Huff, 1978; Mc­Caf­ferty and Pereira, 1984; Mc­Shaf­frey and Mc­Caf­ferty, 1986; Mc­Shaf­frey, 1996; Meyer, 2009; Schwiebert, 2007; Wodsedalek, 1912)

• Other Physical Features
• ectothermic
• heterothermic
• bilateral symmetry

• Sexual Dimorphism
• female larger
• male more colorful

• Range wingspan

  8 to 12 mm

  0.31 to 0.47 in

De­vel­op­ment

Like other mayfly species, Ste­nacron in­ter­punc­ta­tum is hemimetabolous. Eggs most often are laid on the sur­face of rivers and streams and sub­se­quently sink to the bot­tom. Polar caps at each end of the eggs serve as at­tach­ment struc­tures, which pre­vent the eggs from drift­ing down­stream to po­ten­tially un­fa­vor­able en­vi­ron­ments. Eggs hatch after about 13 days to 6 weeks.

Mayfly nymphs also are called na­iads. The num­ber of nymph in­stars in S. in­ter­punc­ta­tum is un­known, but nymphs molt about once every two weeks. The growth of nymphs is con­tin­u­ous, though slower dur­ing the colder, win­ter months. Nymphs emerg­ing in the fall are known to over­win­ter. Where S. in­ter­punc­ta­tum nymphs over­win­ter, they mi­grate to deeper wa­ters be­fore ice forms. In the spring thaw, nymphs re­turn to shal­low wa­ters a few days after the ice dis­ap­pears. Un­like other species in the fam­ily Ephemeri­dae, S. in­ter­punc­ta­tum does not emerge all at once on the same day or within a few days. Nymphs are com­monly ob­served through­out the year, though ma­ture nymphs peak in late May or early June. When nymphs emerge later in the breed­ing sea­son, their size at ma­tu­rity is smaller. Lost ap­pendages in S. in­ter­punc­ta­tum nymphs can be re­gen­er­ated.

Emer­gence usu­ally oc­curs in the late af­ter­noon or at sun­set. In na­ture, S. in­ter­punc­ta­tum nymphs re­quire a water tem­per­a­ture of 16° C or greater to begin the process. When a nymph is ready to emerge, it floats to the sur­face of the water in a bub­ble of air and emerges on the sur­face. Al­ter­na­tively, a nymph can crawl up onto a rock, where its cu­ti­cle splits along the me­dial line of the dor­sal part of its body. A mayfly nymph first emerges from the water as a sex­u­ally im­ma­ture winged form called a dun or subimago, and eclo­sion is com­plete after about 5 or 6 min­utes. The subimago flies to a nearby leaf or stem and, after 18 to 22 hours, molts into a re­pro­duc­tive adult called a spin­ner or imago. Mayflies are the only in­sects that molt again after they al­ready have de­vel­oped wings. The adult emer­gence pe­riod ex­tends from April or May through Au­gust or Sep­tem­ber. Adults live for 6 or fewer days.

De­vel­op­ment time varies among broods. Nymphal growth to adult­hood oc­curs within a year, some­times in as lit­tle as a few months dur­ing the sum­mer. Water tem­per­a­ture and the du­ra­tion of de­vel­op­ment af­fect the phys­i­cal char­ac­ter­is­tics of S. in­ter­punc­ta­tum. In­creased water tem­per­a­ture or de­vel­op­ment time pos­i­tively cor­re­lates with the size, in­ten­sity of col­oration, and spot­ting pat­tern of S. in­ter­punc­ta­tum. (Berner and Pescador, 1988; Ed­munds, et al., 1976; Mc­Caf­ferty and Huff, 1978; Mc­Caf­ferty and Pereira, 1984; Meyer, 2009; Schwiebert, 2007; Wodsedalek, 1912)

• Development - Life Cycle
• metamorphosis

Re­pro­duc­tion

Mat­ing flights occur just after sun­set and con­tinue after dark dur­ing the sum­mer. Like most mayfly species, Ste­nacron in­ter­punc­ta­tum adult males form swarms at a dis­crete height above their aquatic habi­tat. The males un­du­late con­tin­u­ously in the swarm. A fe­male fly­ing into the swarm is quickly grabbed by a male, and cop­u­la­tion oc­curs in flight. The two penes of the male are in­serted si­mul­ta­ne­ously into the paired gen­i­tal open­ings of fe­males dur­ing cop­u­la­tion. Ster­nacron in­ter­pun­cata­tum mates once in its life­time. Males die shortly after mat­ing.

Al­though S. in­ter­punc­ta­tum usu­ally re­pro­duces sex­u­ally, un­fer­til­ized eggs of this species have de­vel­oped under ex­per­i­men­tal con­di­tions. (Berner and Pescador, 1988; Ed­munds, et al., 1976; Meyer, 2009; Mingo, 1978; Schwiebert, 2007)

• Mating System
• monogamous

Fe­males lay their eggs within min­utes or hours of mat­ing. To oviposit, a fe­male as­cends and de­scends in flight above the water. She touches her ab­domen on the sur­face of the water, re­leas­ing a por­tion of her eggs each time she de­scends. Ste­nacron in­ter­punc­ta­tum fe­males usu­ally die shortly after oviposit­ing. In the lab­o­ra­tory, eggs hatch after about 13 days, but hatch­ing can take up to 6 weeks. In na­ture, S. in­ter­punc­ta­tum eggs usu­ally hatch in the early fall and early spring.

Pop­u­la­tions of Ste­nacron in­ter­punc­ta­tum can ex­hibit com­plex re­pro­duc­tive cy­cles. The re­pro­duc­tive cycle varies markedly among pop­u­la­tions, likely de­pend­ing on water tem­per­a­tures and other en­vi­ron­men­tal fac­tors. For ex­am­ple, these mayflies can be bi­vol­tine in warm streams and uni­vol­tine with over­lap­ping broods in cold streams. In one In­di­ana stream, three broods of S. in­ter­punc­ta­tum emerge each year. These broods emerge in the early spring, mid­sum­mer, and late sum­mer or early fall. In other areas, such as Florida, adults emerge every month. The com­plex breed­ing sys­tem in S. in­ter­punc­ta­tum en­sures that in­di­vid­u­als at var­i­ous stages of ma­tu­rity can be found through­out the year, which may re­duce in­traspe­cific com­pe­ti­tion due to re­source par­ti­tion­ing in time. The com­plex life cycle also may fa­cil­i­tate ge­netic mix­ing.

While S. in­ter­punc­ta­tum usu­ally re­pro­duces sex­u­ally, partheno­gen­e­sis has been ob­served in the species under ex­per­i­men­tal con­di­tions. (Berner and Pescador, 1988; Ed­munds, et al., 1976; Flow­ers and Hilsen­hoff, 1978; Giber­son and MacKay, 1991; Lamp and Britt, 1981; Mc­Caf­ferty and Huff, 1978; Mc­Caf­ferty and Pereira, 1984; Meyer, 2009; Rowe and Berrill, 1989; Snucins, 2003; Wodsedalek, 1912)

• Key Reproductive Features
• semelparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• parthenogenic
• sexual
• asexual
• fertilization
  • internal
• oviparous

• Breeding interval

  Stenacron interpunctatum individuals breed once in their lifetime.

• Breeding season

  Courtship, mating, and oviposition occur during the summer, mostly between May and August.

Ste­nacron in­ter­punc­ta­tum likely pro­vides pro­vi­sion­ing in its eggs, but pro­vides no fur­ther parental care.

• Parental Investment
• pre-hatching/birth
  • provisioning
    • female

Lifes­pan/Longevity

Mayflies have the short­est adult lifes­pan of any liv­ing in­sect. In na­ture, Ste­nacron in­ter­punc­ta­tum lives for 6 or fewer days after molt­ing into a re­pro­duc­tive adult. Ste­nacron in­ter­punc­ta­tum can be raised eas­ily in the lab­o­ra­tory; adult fe­males have been kept alive in the lab for up to 8 days. (Funk, et al., 2010; Mc­Caf­ferty and Huff, 1978; Mc­Shaf­frey and Mc­Caf­ferty, 1986; Wodsedalek, 1912)

• Range lifespan
  Status: wild

  6 (high) days

• Range lifespan
  Status: captivity

  8 (high) days

• Typical lifespan
  Status: wild

  6 (high) days

Be­hav­ior

Ste­nacron in­ter­punc­ta­tum is a poor swim­mer as a nymph. It can swim only by un­du­lat­ing its body and usu­ally just drifts or crawls along the bot­tom of its aquatic habi­tat. Nymphs are noc­tur­nal and neg­a­tively pho­to­tac­tic. They in­stinc­tively move away from light and usu­ally rest under stones dur­ing the day. At night, they shift to upper, cur­rent-ex­posed sur­faces. Nymphs be­hav­iorally reg­u­late their oxy­gen con­sump­tion, mov­ing to­ward higher-cur­rent wa­ters when dis­solved oxy­gen con­cen­tra­tions are low. Nymphs also are pos­i­tively thig­mo­tac­tic; they pre­fer to cling to rocks and other ob­jects.

Adults are able to fly. Males fly and drift in large un­du­lat­ing swarms above the water to at­tract mates. Dis­per­sal can occur by means of wind­blown adult fe­males, pos­si­bly wind­blown eggs, and egg at­tach­ment to the bod­ies of birds.

Nymphs over­win­ter in colonies, while males gather in large groups dur­ing their short life span. (Berner and Pescador, 1988; Ed­munds, et al., 1976; Heise, 1992; Meyer, 2009; Schwiebert, 2007; Snucins, 2003; Wiley and Kohler, 1980; Wodsedalek, 1912)

• Key Behaviors
• flies
• glides
• nocturnal
• motile
• sedentary
• colonial

Home Range

Ste­nacron in­ter­punc­ta­tum nymphs are poor swim­mers, and adults live for just a few days. In­di­vid­u­als likely stay close to their orig­i­nal habi­tat through­out their lives, un­less winds or birds fa­cil­i­tate pas­sive dis­per­sal. (Ed­munds, et al., 1976; Schwiebert, 2007; Snucins, 2003; Wodsedalek, 1912)

Com­mu­ni­ca­tion and Per­cep­tion

Ste­nacron in­ter­punc­ta­tum nymphs are neg­a­tively pho­to­tac­tic; they can de­tect and move away from light. They are not sen­si­tive to in­frared light, but they move away from sun­light and green or red lights. Their vi­sion is not very good; some ev­i­dence in­di­cates that nymphs can­not see small ob­jects. Nymphs are pos­i­tively thig­mo­tac­tic, pref­er­en­tially cling­ing to rocks or other ob­jects. The labium of a nymph, used for feed­ing, con­tains hair­like setae that may de­tect me­chan­i­cal and chem­i­cal stim­uli.

Adults have large com­pound eyes that oc­cupy most of the space on their head. Vi­sion seems to be their most im­por­tant means of per­cep­tion and com­mu­ni­ca­tion, prob­a­bly play­ing an im­por­tant role in lo­cat­ing patches of food and avoid­ing preda­tors. (Heise, 1992; Mc­Shaf­frey, 1996; Meyer, 2009; Wodsedalek, 1912)

• Communication Channels
• visual

• Perception Channels
• visual
• tactile
• chemical

Food Habits

Ste­nacron in­ter­punc­ta­tum nymphs are gen­er­al­ist her­bi­vores, eat­ing di­atoms, other algae, and scav­enged aquatic plants. They are op­por­tunis­tic col­lec­tors/gath­er­ers that ex­hibit a "be­hav­ioral cycle" of feed­ing, which in­volves brush­ing food ma­te­r­ial from the sub­stra­tum of their aquatic habi­tat, gath­er­ing de­tri­tus, and pas­sively fil­ter­ing de­tri­tus from the cur­rent. De­tri­tus com­prises about 97% of the par­ti­cles eaten by nymphs and 91.6% of their en­ergy in­take (caloric con­tent). While their eyes do not play a di­rect role in ob­tain­ing food, vi­sion may be im­por­tant in lo­cat­ing food patches. A nymph gath­ers food using its labium, which con­tains sim­ple hair­like setae that prob­a­bly serve as mechanore­cep­tors. Other setae on the labium re­sem­ble the chemore­cep­tors of other aquatic in­sect species. These setae help S. in­ter­punc­ta­tum to fil­ter, trap, re­tain, and push food par­ti­cles in its mouth. Its mandibles are asym­met­ri­cal, curved, and roughly tri­an­gu­lar. In­stead of bit­ing or chew­ing, an S. in­ter­punc­ta­tum nymph uses its mandibles to re­move ma­te­r­ial from its max­il­lary palps and pack food into its mouth. Nymphs can use their forelegs to scrape plant or algae ma­te­r­ial from sur­faces. The forelegs also trans­port the col­lected food to the mouth of the in­sect.

The mouth­parts of S. in­ter­punc­ta­tum adults are ves­ti­gial; adults do not feed. In fact, the adult di­ges­tive sys­tem is filled with air, which makes the adults light enough to float. (Lamp and Britt, 1981; Mc­Shaf­frey and Mc­Caf­ferty, 1986; Mc­Shaf­frey, 1996; Meyer, 2009; Rowe and Berrill, 1989)

• Primary Diet
• herbivore
  • algivore
• detritivore

• Plant Foods
• algae
• phytoplankton

• Other Foods
• detritus

• Foraging Behavior
• filter-feeding

Pre­da­tion

Ste­nacron in­ter­punc­ta­tum nymphs feign death as a de­fense re­sponse, es­pe­cially if they are re­moved from the water. They con­tinue to feign death even if they are han­dled roughly. This an­tipreda­tor re­sponse lasts an av­er­age of 2 to 3 min­utes but can be sus­tained for up to 65 min­utes.

Preda­tors of S. in­ter­punc­ta­tum in­clude Parag­netina fu­mosa (stone­fly), My­otis lu­cifu­gus (lit­tle brown bat), fish, and other aquatic an­i­mals. (Clare, et al., 2011; Meyer, 2009; Pon­tasch, 1988; Wodsedalek, 1912)

• Known Predators

  • Paragnetina fumosa
  • Myotis lucifugus
  • Fish

Ecosys­tem Roles

Ste­nacron in­ter­punc­ta­tum may be an im­por­tant source of food for Parag­netina fu­mosa (stone­fly), My­otis lu­cifu­gus (lit­tle brown bat), fish, and other aquatic wildlife. (Clare, et al., 2011; Meyer, 2009; Pon­tasch, 1988; Wodsedalek, 1912)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Along with other mayfly species, Ste­nacron in­ter­punc­ta­tum is valu­able to hu­mans as an eco­log­i­cal in­di­ca­tor of water qual­ity. Fly fish­ers can use S. in­ter­punc­ta­tum adults as bait; they also tie flies that re­sem­ble S. in­ter­punc­ta­tum. ("Mayflies (Ephemeroptera)", 2013; Mc­Caf­ferty and Huff, 1978; Meyer, 2009)

• Positive Impacts
• ecotourism

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

The sum­mer emer­gence of mayflies can occur in ex­tremely high den­si­ties. Mayflies can be a nui­sance to peo­ple if their dead bod­ies pile up around houses and cars. If mayflies are blown onto roads in high num­bers, the roads can be­come slick and po­ten­tially dan­ger­ous. (Meyer, 2009)

• Negative Impacts
• household pest

Con­ser­va­tion Sta­tus

In gen­eral, mayfly pop­u­la­tions have de­clined dra­mat­i­cally over the past 50 years due to urban de­vel­op­ment and water pol­lu­tion. While mayfly species tend to be sen­si­tive to en­vi­ron­men­tal stress, Ste­nacron in­ter­punc­ta­tum is rel­a­tively ro­bust to some en­vi­ron­men­tal changes and pol­lu­tants. How­ever, the acid­i­fi­ca­tion of aquatic habi­tats caused by an­thro­pogenic pol­lu­tion has af­fected S. in­ter­punc­ta­tum pop­u­la­tions. For ex­am­ple, in a Florida river se­verely im­pacted by cel­lu­lose mill wastes, S. in­ter­punc­ta­tum nymphs were ob­served to have gills that were sig­nif­i­cantly larger than in other pop­u­la­tions. These ab­nor­mal gills prob­a­bly de­vel­oped due to re­duced con­cen­tra­tions of dis­solved oxy­gen caused by pol­lu­tion.

The cur­rent con­ser­va­tion sta­tus of S. in­ter­punc­ta­tum has not been eval­u­ated. (Meyer, 2009; Pescador and Ras­mussen, 1995; Snucins, 2003)

• IUCN Red List

  Not Evaluated

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Other Com­ments

The order Ephemeroptera gets its name from the Greek word "ephemeros", mean­ing "short-lived" and "ptera", mean­ing "wing".

Mayflies have the short­est adult lifes­pan of any liv­ing in­sect. Also, mayflies are an­cient - the ear­li­est species pre­date di­nosaurs. ("Mayflies (Ephemeroptera)", 2013; Funk, et al., 2010)

Con­trib­u­tors

Eliz­a­beth Wason (au­thor), An­i­mal Di­ver­sity Web Staff, An­gela Miner (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

2013. "Mayflies (Ephemeroptera)" (On-line). State Hy­gienic Lab­o­ra­tory at the Uni­ver­sity of Iowa. Ac­cessed June 26, 2013 at http://​www.​shl.​uiowa.​edu/​env/​limnology/​ephemeroptera.​xml.

Berner, L., M. Pescador. 1988. The Mayflies of Florida. Tal­la­has­see and Gainesville: Uni­ver­sity Presses of Florida. Ac­cessed July 02, 2013 at http://​ufdc.​ufl.​edu/​UF00000183/​00001.

Clare, E., B. Bar­ber, B. Sweeney, P. Hebert, M. Fen­ton. 2011. Eat­ing local: in­flu­ences of habi­tat on the diet of lit­tle brown bats (My­otis lu­cifu­gus). Mol­e­c­u­lar Ecol­ogy, 20: 1772-1780. Ac­cessed June 28, 2013 at http://​xa.​yimg.​com/​kq/​groups/​21289390/​869247824/​name/​Clare+etal2011_​+Eating+local+Influences+of+habitat+on+the+diet+of+little+brown+bats.​pdf.

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