Ephemeroptera: Heptageniidae of Gunnison County, Colorado
Epeorus longimanus (Eaton) 1885
Slate Brown Dun, Dark Gordon Quill, Spotted Epeorus
Updated 19 Nov 2020
Beaver Creek, East Elk Creek, Gunnison River, Red Creek, Steuben Creek, Soap Creek and West Elk Creek (Argyle and Edmunds, 1962). Also East River, Avery Creek and Coal Creek.
On this website:
Introduction to Epeorus
Notice the gills meet at the midline, similar to Rhithrogena
Allan, J.D. 1975a. The distributional ecology and diversity of benthic insects in Cement Creek, Colorado. Ecology 56:1040-1053. PDF
Allan,JD 1981 Determinants of diet of brook trout (Salvelinus fontinalis) in a mountain stream. Canadian Journal of Fisheries and Aquatic Sciences 38, 184-192. PDF
Allan,JD 1987 Macroinvertebrate drift in a Rocky Mountain stream. Hydrobiologia 144, 261-268.
The author studied Cement Creek in Gunnison County during the spring, summer and fall of 1975-1978. He found that drift densities (number of animals per 100 m³) was 10 times higher at night. 24 hour totals approached 2000 animals/100m³ in mid-summer down to 500 animals/m³ in the fall. Quote from the abstract: "Ephemeroptera, especially Baetis, dominated the drift." He found that benthic density (number of animals/m² from streambed samples) was the best predictor of 24hr drift rate for Epeorus longimanus. Adding discharge to the calculation (a stepwise regression) did not improve estimates of E. longimanus in the drift.
Allan,JD and Feifarek,BP 1988 Prey preference in stoneflies: a comparative analysis of prey vulnerability. Oecologia, 76(4), pp.496-503.
Argyle,DW; Edmunds,GF 1962 Mayflies (Ephemeroptera) of the Curecanti Reservoir Basins Gunnison River, Colorado. University of Utah Anthropological Papers 59 8, 178-189.
Quote from page 185: "This species is often found with E. albertae in riffle areas. It seems, however to be more tolerant of cold water and usually achieves greater elevation in its distribution. In this particular drainage, it was found at only one station above the distribution of E. albertae. In Blue Creek it was found at 8360 ft., while E. albertae reached only 8300 ft. in the same stream."
Carlisle,Daren M; Clements,William H 2003 Growth and secondary production of aquatic insects along a gradient of Zn contamination in Rocky Mountain streams. Journal North American Benthological Society 22(4), 582-597. Abstract and entire paper
Dodds,GS 1923 Mayflies from Colorado: descriptions of certain species and notes on others. Transactions of American Entomological Society 69, 93-116. PDF
Discussed as Iron longimanus.
Eaton AE. 1883-1888. A revisional monograph of recent Ephemeridae or mayflies. Transactions of the Linnean Society of London, Second Series, Zoology 3:1-352, 65 pl.
Described as Iron longimanus.
Edmunds,GF; Allen,RK 1964 The Rocky Mountain species of Epeorus (Iron) Eaton (Ephemeroptera: Heptageniidae. Journal of the Kansas Entomological Society 37 (4) 275-288. PDF
Flecker,AS and Allan,JD 1988 Flight direction in some Rocky Mountain mayflies (Ephemeroptera), with observations of parasitism. Aquatic Insects 10(1):33-42. PDF
Flecker,Alexander S; Allan,J David; McClintock,Nancy L 1988 Male body size and mating sucess in swarms of the mayfly Epeorus longimanus. Holarctic Ecology 11(4), 280-285. PDF
Gilpin,BR and Brusven,MA 1970 Food habits and ecology of mayflies of the St. Maries River in Idaho. Melanderia 4:19-40. PDF
Hamilton,H and Clifford, F 1983 The seasonal food habits of mayfly (Ephemeroptera) nymphs from three Alberta, Canada, streams, with special reference to absolute volume and size of particles ingested. Arch. Hydrobiol., Suppl, 65(2/3), 197-234. PDF
Harper,PP and Harper,F 1997. Mayflies (Ephemeroptera) of the Yukon. Pp. 152-167 In: H.V. Danks and J.A. Downes, eds. Insects of the Yukon. Biological Survey of Canada (Terrestrial Arthropods). Ottawa, Ontario, Canada.
Kiffney,PM; 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.
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
McCafferty,WP; Durfee,RS; Kondratieff,BC 1993 Colorado mayflies (Ephemeroptera): an annotated inventory. Southwestern Naturalist 38 (3) 252-274. PDF
Quote from page 261: "Edmunds and Allen (1964) noted this was the most widespread of the western species of Iron and that it evidently is not found cohabitating with I. albertae." They report Gunnison County Museum specimens from the Crystal River, East River and Gunnison River.
McCafferty,WP and Provonsha, AV The Mayflies of North AmericaSpecies List (Version 8Feb2011)
Here is the geographic range and synonyms:
Epeorus longimanus (Eaton), 1885 [CAN:FN,NW;USA:FN,NW,SW]
* Iron longimanus Eaton, 1885 (orig.)
* Iron proprius Traver, 1935 (syn.)
Peckarsky,BL 1983 Biotic interactions or abiotic limitations? A model of lotic community structure. In: Dynamics of Lotic Ecosystems. Eds: Fontaine III,Thomas D; Bartell,Steven M Ann Arbor Science, Ann Arbor, Michigan, 303-323.
Peckarsky,BL; Encalada,AC and McIntosh,AR 2011 Why do vulnerable mayflies thrive in trout streams?. American Entomologist, 57(3), pp.152-164. PDF
Poff,NL and Ward,JV 1991 Drift responses of benthic invertebrates to experimental streamflow variation in a hydrologically stable stream. Canadian Journal of Fisheries and Aquatic Sciences, 48(10): 1926-1936.
Abstract: Field experiments were conducted in the regulated upper Colorado River to assess drift responses of lotic macroinvertebrates to streamflow manipulations. In each of three seasons, drift was collected in one control and two experimental riffles. On the first day, no flow manipulations occurred. Six hours before sunset on the second day, streamflow was simultaneously reduced and elevated in two experimental riffles with instream diversion structures. Following flow elevation, both mean daily drift density and drift rate generally increased for 13 taxa across all seasons. Flow reductions generally induced elevated drift densities for most taxa, but drift rates declined for some taxa. Patterns of diel drift periodicity were less frequently modified by flow manipulations. Taxa with typical nocturnal peaks in drift activity (Baetis spp., Epeorus longimanus, Triznaka signata) generally maintained this pattern despite some increases in diurnal drift. For a few taxa, modification of diel drift patterns occurred, either as nocturnal decreases following reduced flow (Paraleptophlebia heteronea, Ephemerella infrequens) or as diurnal drift increases in response to either elevated flow (Lepidostoma ormea, Chironomidae larvae) or reduced flow (Simuliidae). With some exceptions, observed drift responses could be used to suggest active versus passive processes of drift entry.
Rader RB and Ward JV. 1988 Influence of regulation on environmental conditions and the macroinvertebrate community in the upper Colorado River. Regulated Rivers: Research and Management 2:597-618.
Heptagenid mayflies were eliminated at the regulated site directly below the dams, but E. longimanus reappeared at the recovery site downstream.
Radford,DS and Hartland-Rowe,R 1971 The life cycles of some stream insects (Ephemeroptera, Plecoptera) in Alberta. The Canadian Entomologist, 103(4) 609-617.
Names have changed since 1971:
Abstract: " The life histories of Nemoura besametsa, Epeorus deceptivus, Epeorus longimanus, and Ephemerella coloradensis are described as "fast seasonal" types and Arcynopteryx aurea, Nemoura cinctipes, Nemoura columbiana, Nemoura oregonensis, Cinygmula ramaleyi, Ephemerella doddsi, and Rhithrogena doddsi as "slow seasonal" types according to Hynes´ (1961) classification. All of the species are univoltine with the exception of N. cinctipes which may be bivoltine. There seems to be a correlation between life cycles and food availability. A means of ecological separation in the four Nemoura species is elucidated. Stream temperature was found to influence growth rates."
The United States Geological Survey (USGS) National Water Quality Assessment Data Warehouse (NAWQA) shows this species is present in Gunnison County. Data as of 1Sep2005
Wellnitz,T 2014 Can current velocity mediate trophic cascades in a mountain stream?. Freshwater Biology, 59(11) 2245-2255. PDF
Brown, WS 2004 Mayflies (Ephemeroptera) of Gunnison County, Colorado, USA
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