Ephemeroptera of Gunnison County, ColoradoIntroduction to Baetidae
Small Minnow Mayflies, Blue-Winged Olives, BWOLeach, 1815
Updated 16 February 2026
TSN 100755
Provisional Species List
Good Links
On this website:
Baetis introduction
Keys
Baetidae nymphs to species
Baetis nymphs to species
Other species that may be present
Centroptilum Introduction
Fallceon quilleri
Other websites:
References
Abernethy,EF; Muehlbauer,JD; Kennedy,TA; Tonkin,JD; Van Driesche,R and Lytle,DA 2021 Hydropeaking intensity and dam proximity limit aquatic invertebrate diversity in the Colorado River Basin. Ecosphere, 12(6), p.e03559. PDF
Allen,RK and Murvosh,CM 1987 New Baetidae from the southwestern United States and northern Mexico (Ephemeroptera: Insecta), with notes. Canadian Entomologist 119, 1095-1099.
Barber-James,HM; Gattolliat,J; Sartori,M and MD Hubbard 2008 Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater. Hydrobiologia 595(1) 339-350. DOI:10.1007/s10750-007-9028-y Abstract and Full Text
Cain,DJ; Luoma,SN; Wallace,WG 2004 Linking metal bioaccumulation of aquatic insects to their distribution patterns in a mining-impacted river. Environmental Toxicology and Chemistry 23, 1463-1473. PDF
Abstract: "Although the differential responses of stream taxa to metal exposure have been exploited for bioassessment and monitoring, the mechanisms affecting these responses are not well understood. In this study, the subcellular partitioning of metals in operationally defined metal-sensitive and detoxified fractions were analyzed in five insect taxa. Samples were collected in two separate years along an extensive metal contamination gradient in the Clark Fork River (MT, USA) to determine if interspecific differences in the metal concentrations of metal-sensitive fractions and detoxified fractions were linked to the differences in distributions of taxa relative to the gradient. Most of the Cd, Cu, and Zn body burdens were internalized and potentially biologically active in all taxa, although all taxa appeared to detoxify metals (e.g., metal bound to cytosolic metal-binding proteins). Metal concentrations associated with metal-sensitive fractions were highest in the mayflies Epeorus albertae and Serratella tibialis, which were rare or absent from the most contaminated sites but occurred at less contaminated sites. Relatively low concentrations of Cu were common to the tolerant taxa Hydropsyche spp. and Baetis spp., which were widely distributed and dominant in the most contaminated sections of the river. This suggested that distributions of taxa along the contamination gradient were more closely related to the bioaccumulation of Cu than of other metals. Metal bioaccumulation did not appear to explain the spatial distribution of the caddisfly Arctopsyche grandis, considered to be a bioindicator of metal effects in the river. Thus, in this system the presence/absence of most of these taxa from sites where metal exposure was elevated could be differentiated on the basis of differences in metal bioaccumulation."
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.
Fritz,KM; Kashuba,RO; Pond,GJ; Christensen,JR; Alexander,LC; Washington,BJ; Johnson,BR; Walters,DM; Thoeny,WT and Weaver,PC 2023 Identifying invertebrate indicators for streamflow duration assessments in forested headwater streams. Freshwater Science, 42(3), pp.247-267. PDF
On page 254 in table 5, the family Baetidae was identified as an indicator for perennial stream reaches based on random forest and indicator species analysis.
Hammock,BG; Krigbaum,NY and Johnson,ML 2012 Incorporating invertebrate predators into theory regarding the timing of invertebrate drift. Aquatic Ecology, 46(2), 153-163. Abstract
Leach,WE 1815 Entomology. Brewster's Edinburgh Encyclopaedia 9:57-172.
Lugo-Ortiz,CR; McCafferty,WP 1998 A new North American genus of Baetidae (Ephemeroptera) and key to Baetis complex genera. Entomological News 109 5, 345-353. PDF
McCafferty,WP; Durfee,RS; Kondratieff,BC 1993 Colorado mayflies (Ephemeroptera): an annotated inventory. Southwestern Naturalist 38 3, 252-274. PDF
McCafferty,WP; Waltz,RD 1990 Revisionary synopsis of the Baetidae (Ephemeroptera) of North and Central America. Transactions of American Entomological Society 116, 769-799.
Meyer,MD; McCafferty,WP 2001 Hagen's small minnow mayfly (Ephemeroptera: Baetidae) in North America. Entomological News 112 4, 255-263.
Morihara,DK; McCafferty,WP 1979 The Baetis larvae of North America (Ephemeroptera:Baetidae). Transactions of American Entomological Society 105, 139-221.
Short,RA; Canton,SP and Ward,JV 1980 Detrital processing and associated macroinvertebrates in a Colorado mountain stream. Ecology, 61(4), 727-732. PDF
Waltz,RD 1986 Revisionary studies of the mayfly family Baetidae (Ephemeroptera). Purdue Univ., dissertation. 259 pp.
Waltz RD and McCafferty,WP 1997 New generic synonymies in Baetidae (Ephemeroptera). Entomological News 108:134-140.
Wang,TQ; McCafferty,WP 1996 New diagnostic characters for the mayfly family Baetidae (Ephemeroptera). Entomological News 107(2) 207-212. PDF
Ward,JV, Kondratieff,BC and Zuellig,RE 2002 An Illustrated Guide to the Mountain Stream Insects of Colorado. 2nd ed. University Press of Colorado, Boulder, Colorado. 219 pages.
Very useful. They briefly summarize the recent taxonomic changes to Baetidae relevent for Colorado on pages 86-88.
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."
Zuellig,RE; Kondratieff,BC and Rhodes,HA 2002 Benthos recovery after an episodic sediment release into a Colorado Rocky Mountain river. Western North American Naturalist 62 (1) 59-72.
Abstract: "During late September 1996, approximately 7000 m3 of clay- to gravel-sized sediment was flushed from Halligan Reservoir, Larimer County, Colorado, into the North Fork Cache la Poudre River during dam inspections. Approximately 9.6 km of this river was partially or completely affected by this episodic sediment release. Pools up to 3.2 km downstream from the dam lost 50% of their volume. Hess samples taken from October 1996 to September 1997, 100 m downstream from the dam (site 1) and 3.2 km downstream (site 2), revealed effects of sediment on recovery patterns of benthic communities. A 2-way ANOVA was used to determine significant interactions using site and date as main factors. Pairwise differences were then compared using least squares means to determine significant dates within and between sites. Ten days after the sediment release, both density and taxa richness at site 1 (55 organisms per m2, 5 taxa) were significantly lower (P < 0.05) than site 2 (1156 organisms per m2 , 25 taxa). These differences remained until June when species richness and densities increased. Plecoptera and Trichoptera colonized from June to September after being eliminated at site 1 and reduced at site 2. No permanently flowing tributaries exist within the study area; therefore, passive downstream drift from such inputs apparently did not influence recovery. Increased densities of taxa such as Baetidae, Hydroptilidae, Hydropsychidae, Chironomidae, Simuliidae, and Oligochaeta occurred plausibly by rapid reproduction. Based on pre-event data, community function completely changed at site 2 from a scraper community to one dominated by collector-gatherers."
Brown,WS 2005 Baetidae Mayflies (Ephemeroptera) of Gunnison County, Colorado www.gunnisoninsects.org Be who you are and say what you feel because those who mind don't matter and those who matter don't mind. --Dr. Seuss |
