Ephemeroptera: Heptageniidae of Gunnison County, ColoradoIntroductionFlat Headed Mayflies, ClingersUnder Construction! Updated 11 January 2026
Provisional Species List
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ReferencesAllan,JD 1981 Determinants of diet of brook trout (Salvelinus fontinalis) in a mountain stream. Canadian Journal of Fisheries and Aquatic Sciences 38, 184-192. PDFAllan,JD 1987 Macroinvertebrate drift in a Rocky Mountain stream. Hydrobiologia 144, 261-268. Allan,JD and Feifarek,BP 1988 Prey preference in stoneflies: a comparative analysis of prey vulnerability. Oecologia, 76(4), pp.496-503. Allan,JD and Feifarek,BP 1989 Distances travelled by drifting mayfly nymphs: factors influencing return to the substrate. Journal of the North American Benthological Society 8 (4) 322-330. Allan,JD; Flecker,AS and McClintock,NL 1986 Diel epibenthis activity of mayfly nymphs, and its nonconcordance with behavioral drift. Limnology and Oceanography 31 (5) 1057-1065. PDF Balistrieri,LS; Mebane,CA and Schmidt,TS 2020 Time-dependent accumulation of Cd, Co, Cu, Ni, and Zn in mayfly and caddisfly larvae in experimental streams: Metal sensitivity, uptake pathways, and mixture toxicity. Science of the Total Environment, 732. html Abstract: "Conceptual and quantitative models were developed to assess time-dependent processes in four sequential experimental stream studies that determined abundances of natural communities of mayfly and caddisfly larvae dosed with single metals (Cd, Co, Cu, Ni, Zn) or multiple metals (Cd + Zn, Co + Cu, Cu + Ni, Cu + Zn, Ni + Zn, Cd + Cu + Zn, Co + Cu + Ni, Cu + Ni + Zn). Metal mixtures contained environmentally relevant metal ratios found in mine drainage. Free metal ion concentrations, accumulation of metals by periphyton, and metal uptake by four families of aquatic insect larvae were either measured (Brachycentridae) or predicted (Ephemerellidae, Heptageniidae, Hydropsychidae) using equilibrium and biodynamic models. Toxicity functions, which included metal accumulations by larvae and metal potencies, were linked to abundances of the insect families. Model results indicated that mayflies accumulated more metal than caddisflies and the relative importance of metal uptake by larvae via dissolved or dietary pathways highly depended on metal uptake rate constants for each insect family and concentrations of metals in food and water. For solution compositions in the experimental streams, accumulations of Cd, Cu, and Zn in larvae occurred primarily through dietary uptake, whereas uptake of dissolved metal was more important for Co and Ni accumulations. Cd, Cu, and Ni were major contributors to toxicity in metal mixtures and for metal ratios examined. Our conceptual approach and quantitative results should aid in designing laboratory experiments and field studies that evaluate metal uptake pathways and metal mixture toxicity to aquatic biota." Carlisle,DM and Clements,WH 2003 Growth and secondary production of aquatic insects along a gradient of Zn contamination in Rocky Mountain streams. Journal of the North American Benthological Society 22 (4) 582-597. PDF Clements,WH; Carlisle,DN; Lazorchak,JM and Johnson,PC 2000 Heavy metals structure benthic communities in Colorado mountain streams. Ecological Applications 10(2)626-638. PDF Abstract: "The development of field sampling designs that employ multiple reference and polluted sites has been proposed as an alternative to the traditional upstream vs. downstream approach used in most biomonitoring studies. Spatially extensive monitoring programs can characterize ecological conditions within an ecoregion and provide the necessary background information to evaluate future changes in water quality. We measured physicochemical characteristics, heavy-metal concentrations, and benthic macroinvertebrate community structure at 95 sites in the Southern Rocky Mountain ecoregion in Colorado, USA. Most sites (82%) were selected using a systematic, randomized sampling design. Each site was placed into one of four metal categories (background, low, medium, and high metals), based on the cumulative criterion unit (CCU), which we defined as the ratio of the instream metal concentration to the U.S. Environmental Protection Agency criterion concentration, summed for all metals measured. A CCU of 1.0 represents a conservative estimate of the total metal concentration that, when exceeded, is likely to cause harm to aquatic organisms. Although the CCU was less than 2.0 at most (66.3%) of the sites, values exceeded 10.0 at 13 highly polluted stations. Differences among metal categories were highly significant for most measures of macroinvertebrate abundance and all measures of species richness. We observed the greatest effects on several species of heptageniid mayflies (Ephemeroptera: Heptageniidae), which were highly sensitive to heavy metals and were reduced by >75% at moderately polluted stations. The influence of taxonomic aggregation on responses to metals was also greatest for mayflies. In general, total abundance of mayflies and abundance of heptageniids were better indicators of metal pollution than abundance of dominant mayfly taxa. We used stepwise multiple-regression analyses to investigate the relationship between benthic community measures and physicochemical characteristics at the 78 randomly selected sites. Heavy-metal concentration was the most important predictor of benthic community structure at these sites. Because of the ubiquitous distribution of heavy-metal pollution in the Southern Rocky Mountain ecoregion, we conclude that potential effects of heavy metals should be considered when investigating large-scale spatial patterns of benthic macroinvertebrate communities in Colorado's mountain streams." Dodds,GS 1923 Mayflies from Colorado: descriptions of certain species and notes on others. Transactions of American Entomological Society 69, 93-116. PDF Dodds,GS and Hisaw,FL 1925 Ecological studies on aquatic insects. IV. Altitudinal range and zonation of mayflies, stoneflies and caddisflies in the Colorado Rockies. Ecology 6(4)380-390. Abstract PDF Edmunds,GF and Allen,RK 1964 The Rocky Mountain species of Epeorus (Iron) Eaton (Ephemeroptera: Heptageniidae. Journal of the Kansas Entomological Society 37 (4) 275-288. Edmunds Jr.,GF; Jensen,SL and Berner,L 1976 The Mayflies of North and Central America. University of Minnesota Press, Minneapolis, Minnesota. 330 pages pages. Flecker,AS; Allan,JD and McClintock,NL 1988 Male body size and mating sucess in swarms of the mayfly Eperorus longimanus. Holarctic Ecology 11 4, 280-285. Herrmann,J; Andersson,KG 1986 Aluminum impact on respiration of lotic mayflies at low pH. Water, Air and Soil Pollution 30, 703-709. Jensen,SL 1966 The Mayflies of Idaho (Ephemeroptera). M.S. Thesis, University of Utah, Utah. 364 p. Jensen,SL and Edmunds,GF Jr. 1973 Some phylogenetic relationships within the Heptageniidae. Pages 82-87 in W. L. Peters & J. G. Peters, eds., Proceedings of the First International Conference on Ephemeroptera, E. J. Brill, Leiden. Kashian DR; Prusha BA and Clements WH. 2004 Influence of total organic carbon and UV-B radiation on zinc toxicity and bioaccumulation in aquatic communities. Environmental Science & Technology. 38(23):6371-6376. Abstract: "The effects of total organic carbon (TOC) and UV-B radiation on Zn toxicity and bioaccumulation in a Rocky Mountain stream community were assessed in a 10-d microcosm experiment. We predicted that TOC would mitigate Zn [zinc] toxicity and that the combined effects of Zn and UV-B would be greater than Zn alone. However, TOC did not mitigate Zn toxicity in this study. In fact, treatments with TOC plus Zn had significantly lower community respiration as compared with the controls and Zn concentrations associated with the periphyton increased in the presence of TOC. UV-B had no additive effect on periphyton Zn accumulation or community respiration. Heptageniid mayflies (Ephemeroptera) were particularly sensitive to Zn, and reduced abundances were observed in all Zn treatments. UV-B did not additionally impact Heptageniid abundances; however UV-B did have a greater effect on macroinvertebrate drift than Zn alone. Ephemeroptera, Plecoptera, and Trichoptera (groups typically classified as sensitive to disturbance) were found in highest numbers in the drift of UV-B + Zn treatments. Measures of Zn accumulation in the caddisfly Arctopsyche grandis, periphyton biomass, and total macroinvertebrate abundance were not sufficiently sensitive to differentiate effects of TOC, UV-B, and Zn. These results indicate that UV-B and TOC affect Zn bioavailability and toxicity by impacting species abundance, behavior, and ecosystem processes. " Kiffney,PM and Clements,WH 1994 Effects of heavy metals on a macroinvertebrate assemblage from a Rocky Mountain stream in experimental microcosms. Journal of the North American Benthological Society 13 4, 511-523. Knopp,M and Cormier,R 1997 Mayflies: An anglers study of trout water Ephemeroptera. Lyons Press, Guilford, CT. 366 pages. Lehmkuhl,DM 1968 Observations on the life histories of four species of Epeorus in western Oregon (Ephemeroptera: Heptageniidae). Pan-Pacific Entomologist 44(2):129-137. PDF Li,R; Lei,Z; Li,W; Zhang,W and Zhou,C 2021 Comparative mitogenomic analysis of heptageniid mayflies (Insecta: Ephemeroptera): Conserved intergenic spacer and trna gene duplication. Insects, 12(2), p.170. Abstract: "Large intergenic spacers and tRNA gene duplications have been reported in several insect groups, although little is known about mitogenomes of mayflies. Here, we determined complete mitogenomes of ten heptageniid species and systemically analyzed their mitogenomic features. Both a conserved intergenic spacer (IGS) and trnM duplication were detected in those mitogenomes. The IGS, which was observed in heptageniids, could be further folded into a stable stem-loop structure. The tRNA gene duplication was found in almost all analyzed mitogenomes, and a unique gene block trnI-trnM-trnQ-trnM-ND2 was also discovered. Our analysis demonstrates that the heptageniid gene arrangement pattern can be explained by the tandem duplication-random loss (TDRL) model. Phylogenetic analyses using both Bayesian inference (BI) and maximum likelihood (ML) methods based on the nucleotide and amino acid sequence data recovered the genus Epeorus as monophyletic with strong support. Our results provide a better understanding of mitogenomic evolution in Heptageniidae, as well as novel molecular markers for species identification of mayflies." Lugo-Ortiz,CR; McCafferty,WP 1995 Annotated inventory of the mayflies (Ephemeroptera) of Arizona. Entomological News 106 3, 131-140. McIntosh,AR; Peckarsky,BL and Taylor,BW 2002 The influence of predatory fish on mayfly drift: extrapolating from experiments to nature. Freshwater Biology 47, 1497-1513. Peckarsky,BL 1988 Why predaceous stoneflies do not aggregate with their prey. Internationale Vereinigung für Theoretische und Angewandte Limnologie Verhandlungen 23, 2135-2140. Peckarsky,BL 1991 Is there a coevolutionary arms race between predators and prey? A case study with stoneflies and mayflies. Advances in Ecology 1, 167-180. Peckarsky,BL 1996 Alternative predator avoidance syndromes of stream-dwelling mayfly larvae. Ecology 77 6, 1888-1905. Peckarsky,BL and Cowan,CA 1995 Microhabitat and activity periodicity of predatory stoneflies and their mayfly prey in a western Colorado stream. Oikos 74 3, 513-521. Rackliffe,DR and Hoverman,JT 2020 Population-level variation in neonicotinoid tolerance in nymphs of the heptageniidae. Environmental Pollution, p.114803. html The authors studied several genera of Heptageniidae not found in Colorado. Tolerances for neonicotinoid pesticides varied not only between genera, but also between populations of the same species in different locations. Quote from the abstract: "Our data suggest that populations of Heptageniidae mayflies can vary substantially in neonicotinoid tolerance. Population-level variation should be considered in toxicity assessments and presents the potential for evolved tolerance." Sinitshenkova,ND and Grimaldi,D 2000 New Jersey amber mayflies: the first North American Mesozoic members of the order (Insecta; Ephemeroptera). Studies on Fossils in Amber, with Particular Reference to the Cretaceous of New Jersey. Backhuys Publishers, Leiden, Netherlands, pp.111-125. PDF Abstract: "The following new genera and species of mayflies are described from Upper Cretaceous (Turonian) amber from Sayreville, New Jersey, U.S.A: Cretomitarcys luzzii (imago male), (Polymitarcyidae: Cretomitarcyinae, new subfamily), Borephemera goldmani (imago male, Australiphemeridae), Amerogenia macrops (imago female) (Heptageniidae) and Palaeometropus cassus (subadult male) (Ametropodidae). Previously no mayflies were described from the Mesozoic of North America. Ametropodidae and Heptageniidae are newly recorded for the Mesozoic, and Australiphemeridae for the Upper Cretaceous. The mayflies in this amber probably inhabited a medium-sized or large river. Zoogeography of Upper Cretaceous mayflies is briefly discussed; with particular emphasis on significant faunistic differences between the temperate and subtropical areas." Traver,JR 1935 Two new genera of North American Heptageniidae (Ephemerida). Canadian Entomologist 67:31-38. Abstract: "Through the courtesy of Dr. McDunnough, I have recently been permitted to study many specimens of mayflies allied to the genus Iron, which were collected in Western Canada. Imagoes of both sexes and correctly associated nymphs of several species were included in the material, which was loaned to me from the Canadian National Collection. A study of these specimens, together with others in the Cornell University Collection, convinces me that two new genera are represented, which I designate respectively as Ironodes and Ironpsis." Wang,T-Q and McCafferty,WP 1995 Relationships of Arthropleidae, Heptageniidae, and Pseudironidae (Ephemeroptera: Heptagenioidea). Entomological News 106 (5) 251-256. PDF Abstract: "Phylogenetic relationships indicate that Pseudiron represents a sister lineage to all other genera that have traditionally been placed in the family Heptageniidae. Among the latter lineage, Arthroplea represents a sister lineage to a lineage including all other genera. Recognition of the families Pseudironidae (Pseudiron). Arthropleidae (Arthroplea). and Heptageniidae sensu stricto is suggested within the framework of a strictly phylogenetic classification. The deduced cladogram of the three lineages and their apomorphic characterization is presented." Wang,T-Q and McCafferty,WP 2004 Heptageniidae (Ephemeroptera) of the world. Part I: Phylogenetic higher classification. Transactions of the American Entomological Society 130(1): 11-45. Abstract: "Twenty-nine monophyletic species groups based on the study of nearly 200 species of the Ephemeroptera family Heptageniidae from North and Central America, Africa, Eurasia, and Southeast Asia were subjected to cladistic analysis in order to hypothesize their interrelationships and produce a framework for a strict phylogenetic higher classification for the family. As a result, three sequentially derived major clades are recognized as the subfamilies Ecdyonurinae, Heptageniinae, and Rhithrogeninae. The Ecdyonurinae is divided into four tribes: the Ecdyonurini, containing the genera Nixe Flowers and Ecdyonurus Eaton; the Leucrocutini, n. trib., containing the genera Siberionurus McCafferty and Leucrocuta Flowers; the Notacanthurini, n. trib., containing the genera Notacanthurus Tshernova and Electrogena Zurwerra and Tomka; and the Atopopini, n. trib., containing the genera Afronurus Lestage [=Cinygmina Kimmins, n. syn.], Asionurus Braasch and Soldán, Thalerosphyrus Eaton [=Compsoneuriella Ulmer, n. syn.; =Notonurus Crass, n. syn.], and Atopopus Eaton. The Heptageniinae is divided into four tribes: the Compsoneuriini, n. trib., containing the genera Compsoneuria Eaton and Trichogenia Braasch and Soldán; the Heptageniini, containing the genera Heptagenia Walsh, Dacnogenia Kluge, n. stat., and Raptoheptagenia Whiting and Lehmkuhl; the Kageroniini, n. trib., containing the genera Kageronia Matsumura [=Parastenacron Kluge, n. syn.] and Stenacron Jensen; and the Stenonematini, n. trib., containing the genera Macdunnoa Lehmkuhl, Maccaffertium Bednarik, n. stat., and Stenonema Traver. The Rhithrogeninae is divided into four tribes: the Rhithrogenini, containing the genera Paegniodes Eaton, Rhithrogena Eaton [=Rhithrogeniella Ulmer, n. syn.], and Cinygmula McDunnough [=Epeiron Demoulin, n. syn.; =Ororotsia Traver, n. syn.]; the Cinygmatini, containing the genus Cinygma Eaton [=Cinygmoides Matsumura, n. syn.]; the Epeorini, n. trib., containing the genera Bleptus Eaton, Ironodes Traver, and Epeorus Eaton [=Epeorella Ulmer, n. syn.]; and the Anepeorini, containing the genera Anepeorus McDunnough [=Acanthomola Whiting and Lehmkuhl, n. syn.] and Spinadis Edmunds and Jensen. The nomenclatural history of the higher classification of the family, bases for the new classification and synonymies, and the biogeography and evolution of the genera are discussed." Webb,JM and McCafferty,WP 2008 Heptageniidae of the world. Part II. Key to the genera. Canadian Journal of Arthropod Identification, 7(10.37551). PDF Ward,JV and Berner,L 1980 Abundance and altitudinal distribution of Ephemeroptera in a Rocky Mountain stream. In Advances in Ephemeroptera biology (pp. 169-177). Springer US. PDF Abstract: "The nymphs of 29 species of Ephemeroptera representing six families were collected from rubble riffles in a Colorado stream system, from alpine tundra to the plains. Density ranged from 44 nymphs/m2 at the headwater site to 2,031 nymphs/m2 in the Foothills Limnological Zone. Heptageniidae comprised the majority of the mayflies at upstream sites and were numerically important at all but the plains location. Baetidae attained maximum diversity and relative abundance (62% of total mayflies) in the plains stream. Seven species of Ephemerella exhibited overlapping distribution patterns from 3109 m a.s.l to the plains." Ward,JV and Stanford,JA 1990 Ephemeroptera of the Gunnison River, Colorado, USA. In: Mayflies and Stoneflies. Ed: Campbell,IC Kluwer Academic Publishers, 215-220. PDF Abstract: "Samples were taken year-round at eleven sites (2900-1400m a.s.l.) along the Gunnison River, a 329 km long tributary of the Colorado River, to examine the longitudinal distribution of Ephemeroptera and to assess the response of the mayfly fauna to dams in the headwaters and middle reaches. Nymphal abundance increased from headwaters (791 organisms and 333mg dry weight m-2 at site 1) to lower reaches (2610 organisms and 873 mg at Site 11). Abundance was slightly elevated immediately below the headwater dam (Site 2) whereas damming the middle reaches greatly reduced mayfly density and biomass. Five families (Baetidae, Ephemerellidae, Heptageniidae, Leptophlebiidae, Tricorythidae) comprised from > 98% to 100% of the mayfly fauna at each site. Leptophlebiids and tricorythids were abundant only in the lower reaches. Mayfly species richness exhibited a unimodal pattern with the maximum at Site 4. Both headwater and middle reach dams greatly reduced species richness immediately downstream. Scrapers and collector-gatherers comprised the majority of the mayfly fauna at all sites. Filter-feeders were abundant only at Site 11 where Traverella albertana attained high densities." Webb,JM 2007 Diversity and identification of heptageniid mayflies (Insecta: Ephemeroptera) of the world (Doctoral dissertation, Purdue University). Webb,JM and McCafferty,WP 2008 Heptageniidae of the world. Part II. Key to the genera. Canadian Journal of Arthropod Identification, 7(10.37551). PDF Abstract: "Keys and diagnoses illustrated with line drawings and colour photographs for the identification of larvae and adult males of the genera of Heptageniidae of the world and female adults of North American Heptageniidae genera are provided. Siberionurus McCafferty is recognized as a junior objective synonym of Ecdyogymnurus Kluge. Epeiron Demoulin is shown to be congeneric with Rhithrogena Eaton. All subgenera that have been proposed for Rhithrogena, Compsoneuria Eaton, and Epeorus Eaton are treated as junior synonyms (Rhithrogena = Himalogena Kluge, N.SYN.; = Sibirigena Kluge, N.SYN.; = Tumungula Zhou & Peters, N.SYN.; Epeorus = Alpiron Braasch, N.SYN.; = Albertiron Kluge, N.SYN.; = Belovius Tshernova; = Caucasiron Kluge, N.SYN.; = Iron Eaton; = Ironopsis Traver; = Proepeorus Kluge, N.SYN.; Compsoneuria = Siamoneuria Braasch, N.SYN.)" Zuellig,RE; Kashian,DR; Brooks,ML; Kiffney,PM and Clements,WH 2008 The influence of metal exposure history and ultraviolet-B radiation on benthic communities in Colorado Rocky Mountain streams. Journal of the North American Benthological Society, 27(1), 120-134. PDF Brown,WS 2004 Mayflies (Ephemeroptera) of Gunnison County, Colorado, USA www.gunnisoninsects.org "Violence is the last refuge of the incompetent" -- Issac Asimov |